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Making Room forNative PollinatorsHow to Create Habitat for Pollinator Insects on Golf Coursesby Matthew Shepherd, The Xerces Society

Copyright© 2002 ByTHE UNITED STATES GOLF ASSOCIATION AND

THE XERCES SOCIETY

All Rights Reserved

Printed in the United States of America

Making Room forNative PollinatorsHow to Create Habitat for Pollinator Insects on Golf Courses

Matthew Shepherd

Pollinator Program Director, The Xerces Society

Recycled Paper

Cover:Flower-flies, like this drone fly, are often mistaken for bees. They play an important role as a pollinator.

Photo Credits:Cover and page 10 — James CanePages three and four — Edward S. RossRemaining photos — The Xerces Society and USGA

M A K I N G R O O M F O R N A T I V E P O L L I N A T O R S

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Table of Contents

Introduction............................................................................................................................................................... 2

Pollinators, the Forgotten Link in the Chain of Life ................................................................................... 3

Bees, the dominant pollinators ......................................................................................................................... 3

The threats bees face ............................................................................................................................................. 4

Gentle pollinators................................................................................................................................................... 4

The Natural History of Bees................................................................................................................................ 5

Complete metamorphosis.................................................................................................................................... 5

Solitary nesting bees.............................................................................................................................................. 6

Bumble bees.............................................................................................................................................................. 7

Cuckoo bees .............................................................................................................................................................. 8

Helping the Forgotten Pollinators..................................................................................................................... 8

Creating Foraging Habitat ................................................................................................................................... 9

Choosing the right flowers ................................................................................................................................. 9

Table 1: Native plants for bees and other pollinator insects ................................................................. 12

Table 2: Garden plants for bees and other pollinator insects ............................................................... 13

Where to plant ...................................................................................................................................................... 13

What to plant......................................................................................................................................................... 15

Deciding how many plants ............................................................................................................................... 15

Establishing and growing pot-grown transplants..................................................................................... 16

Using wildflower seed......................................................................................................................................... 17

Habitat management .......................................................................................................................................... 18

Bee Nesting Sites................................................................................................................................................. 18

Nesting sites for ground-nesting bees ........................................................................................................... 19

Nesting sites for wood-nesting bees ............................................................................................................... 20

Bumble bee nests.................................................................................................................................................. 21

Conclusions ............................................................................................................................................................ 22

Appendix A: Bee Stings and How to Avoid Them .................................................................................... 23

Appendix B: Useful Resources ........................................................................................................................ 25

Books and Journals .............................................................................................................................................. 25

Nonprofit organizations and companies ..................................................................................................... 25

Internet sites .......................................................................................................................................................... 26

Acknowledgements ............................................................................................................................................ 28


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IntroductionOn golf courses across the country wildflowers bloom, birds nest, mammals feed, lizardsbask, bats roost, and butterflies sip nectar. Given this diversity of wildlife, it is not surprisingthat golf courses are recognized as being increasingly important for nature conservation.Golf courses offer comparatively stable areas within an ever-changing landscape in whichwildlife can find refuge. As development and agriculture impact our environment, naturalhabitat in both urban and rural locations is being lost, fragmented, and degraded. In manyareas, golf courses provide the only significant areas of greenspace and habitat, a resourcethat can support birds, mammals, reptiles, and insects. From secure places on golf courses,wildlife can spread back into the surrounding areas, replenishing and strengthening the populations that survive in the degraded landscape. In addition to this wider significance ofthe on-course habitats, the chance to view wildlife of all sorts adds an extra pleasure forboth players and staff on the course.

Many golf courses are lovingly tended and manicured to create park-like conditions. Somegolfers admire this condition, but the creation and upkeep of such landscapes demandshighly intensive maintenance. The images of these park-like courses in travel brochures andon television contribute to a perception among the general population that golf courses aredead landscapes, treated with excessive amounts of chemicals. The reality is very different.

Superintendents are actively exploring innovative ways to reduce chemical inputs and to findalternative methods to maintain golf courses to the standards expected by players. There aremany examples of good practice where golf course management provides high quality playingconditions, an attractive environment, and good habitat for wildlife. Golf courses offer twomajor opportunities for wildlife conservation: protection of existing areas of natural vegetation,and creation of new habitats in which animal and insect communities can thrive.

As with all greenspace, the value of a golf course for wildlife will be greatly increased ordiminished by the decisions and actions of its managers. When properly planned and managed,a golf course can provide high quality and diverse habitat for a wide range of wildlife. Mosthabitat is managed is for the big, obvious wildlife, such as mammals or birds, and it isassumed that if the habitat is fine for these animals, the smaller critters will cope as well.However, by considering the details of the habitat, you can provide for the particular needs ofmany more creatures. These guidelines are focused on providing habitat for pollinatorinsects, one of the most important groups of creatures.

The importance of good stewardship of golf courses has been recognized internationally. InGreat Britain, for example, the Royal and Ancient Golf Club of St. Andrews has been at theforefront of promoting better management of golf’s natural heritage, supporting both inno-vative management and the dissemination of information. Similarly, the United States GolfAssociation has played a leading role in this country. Through its own publications theUSGA promotes new ideas and debate, and through the Wildlife Links Program (adminis-tered by the National Fish and Wildlife Foundation) it provides grants to support researchinto the environmental impacts of course management and developing good managementpractice. Audubon International, a nonprofit that runs the Cooperative Sanctuary Programfor Golf Courses encourages courses to care for wildlife. The Xerces Society benefited from aUSGA grant, and with help from the U.S. Department of Agriculture Bee Biology andSystematics Laboratory, studied the conservation of native pollinators, especially of bees, ongolf courses. These guidelines have been prepared as a result of that project.

Pollinators, the Forgotten Linkin the Chain of LifeIf you are thinking that pollinators aren’timportant to you directly, think again.Pollinators are profoundly important to ourwell-being and the health of our environ-ment. It has been estimated that one out ofevery three mouthfuls of food we eat, andof the beverages we drink, is delivered to usby pollinators. In the U.S. alone, there aremore than one hundred crop plants thatneed pollinators, without which grocerystore shelves would not be so well stocked.Pollinators are also essential componentsof the habitats and ecosystems that manywild animals rely on for food and shelter.For example, approximately 25 percent ofbirds include fruit or seeds, the result ofpollination, as a major part of their diet.

Pollination, the transfer of pollen from oneflower to another, is a vital stage in the lifecycle of all flowering plants, something thatwe all rely on for food and a healthy envi-ronment. Admittedly, a small percentage ofplant species rely on wind (the bane of peoplewho suffer from hay fever and allergies!) oreven water to transfer pollen, but the vastmajority — about 90 percent of all plantspecies — need the help of pollinating animals. There are many different animalsthat act as pollinators in North America,including hummingbirds and bats, but themost important are insects. Butterflies,moths, flies, and beetles are all valuablepollinators, but bees — especially our nativebees — are the most important. Togetherthey fulfill a critical function in our lives,but too often their presence is taken forgranted and we forget that, like all livingcreatures, we need to care for them.

Bees, the dominant pollinators.

Bees, particularly native bees, are consideredthe most important group of pollinators.The reason for this is simple: female bees

collect nectar and pollen from flowers tocarry back to their nests as food for theiroffspring. In doing so they carry largequantities of pollen from flower to flower.Insects like butterflies, beetles, and fliesalso feed on nectar and pollen — as dohummingbirds and a few bats — but don’tcollect it or purposefully transport it. Somepollen gets stuck to these as they feed, andthus moved to the next flower, but this is a

small amount and entirely by chance. Bycontrast, a single female bee may visit tensor even hundreds of flowers on a foragingtrip, actively gathering and moving pollen.Both male and female bees feed on nectar,but only the female will gather forage totake back to her nest. (The life of a male beeis only to feed and mate.) Although beeshave special structures on their legs andbodies in which to carry the pollen, someof it is brushed off when they visit otherflowers, providing the fundamental serviceof pollination.

The plant communities maintained by pollinators are an important resource forother wildlife that relies on them for foodor shelter. The loss of pollinators results inthe disruption of plant communities inwildland ecosystems, and has serious, long-


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Leaf cutter bee(Megachile sp.) on blanket flower(Gaillardia aristata).

term implications for many animal andinsect populations. The impact of pollinatordeclines is already being seen in communi-ties of some rare plants whose reproductionis limited by a lack of pollinators. Oftenthese plants now rely on human interven-tion for their survival. For example, thefate of the rare Ute lady’s tresses orchid

(Spiranthes diluvialis), which grows in Coloradoand Utah, hinges on adequate pollination,and the presence of the pollinators (twospecies of bumble bees) depends on adequatehabitat. The bumble bees need secure nest-ing sites and a diversity of foraging plantsthrough the summer. If these do not exist,the bumble bees will not be there whenthe orchid needs them. It is the responsibil-ity of the rangeland managers to controlgrazing and pesticide use to ensure theright conditions persist for both orchidsand bees.

The Threats Bees Face

Native bees are in decline and, in places,suffering local extinction. Like all wildlife,native bees and other pollinators are suffer-ing from destruction of their habitat.Intensive agriculture and forestry, housing,

infrastructure, and industry destroy andfragment wild areas. Pesticides have devas-tated pollinator populations, and pose a constant threat to the remaining popula-tions. The native habitat that remainsoften is in isolated patches and is degradedby pesticides, invasive plant species, andchanges in land management. Althoughhabitat fragmentation is not as dramatic asdestruction, it is a serious challenge to thesurvival of many bees. Native bees need bothplants for foraging and suitable nestingsites. Isolated patches of habitat may haveone but not the other, and thus will not beable to support viable bee populations.

Fortunately, populations of many native beesare quite resilient and can survive, thoughnot necessarily thrive, despite habitat dep-rivations. Additionally, they respond wellto the provision of a few of their necessaryresources of foraging plants and nestingsites. Golf courses can provide an importantrefuge for bees and other pollinating insects.In some areas the course may be the onlysignificant area of greenspace with relativelynatural vegetation. By taking some simplesteps to establish patches of native wildflowers and nesting sites, golf courses cansupport thriving populations of pollinators,which in turn will help maintain healthyplant communities in wild lands and supportfull harvest on farms and in backyards.

Gentle pollinators

When people think of bees they tend to picture a fat bumble bee or swarms of honeybees, or confuse them with yellowjacketsand other wasps, and regale you with talesof being stung. In reality, these are theexceptions. It is only the bees that live in acolony or hive (“social bees,” i.e., bumblebees and the non-native, European honeybee) that are likely to sting, because theyhave a colony to defend. Even then most arenot aggressive: of the forty-five species ofbumble bees in the U.S., only four or fivehave a feisty nature when close to their nest.


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Sweat bees are generalists, able to exploit a wide range of flowers and survive indegraded or weedy plant communities.

The rest of our native bees — nearly fourthousand species — live on their own (“solitary-nesting”) and thus have no hive to defend. To lessen the chances even further,the stinger of many species of bee is tooweak to penetrate human skin, and malesdon’t even have a stinger. When foragingaway from the nest no bee is looking forconflict and will only sting (if it can) as a lastresort — maybe because it is being swattedor squashed, or is accidentally caught insomeone’s clothes.

Since most don’t fit the stereotyped imageof a bee — black-and-yellow-striped, livingin a hive with thousands of others, and aptto sting — they are easily overlooked. Out of sight and out of mind, they gently geton with the task of foraging to supply theirnests, and in doing so provide the vitalecosystem service of pollination.

Pollinator conservation will not create arisk for golfers or staff. You are likely to havemore problems from the yellowjacketsattracted to trashcans than you will fromnative bees.

The Natural History of BeesThere is an astonishing diversity of nativebees across North America. About fourthousand species have been identified andcatalogued, ranging in length from lessthan one eighth of an inch to more thanone inch. They vary in color from darkbrown or black to metallic green and blue,and may have stripes of red, white, orange,or yellow. Many common names reflect theway they build nests: plasterer bees, leaf-cutter bees, mason bees, carder bees, diggerbees, and carpenter bees. Others are namedafter particular traits, such as cuckoo beesthat lay eggs in the nests of other bee species(like the cuckoo bird), sweat bees that liketo drink salty perspiration, or bumble bees,which got their name from the loud hum-ming noise they make while flying.

Complete metamorphosis

Like a butterfly, a bee changes totally fromits immature stage to an adult (“completemetamorphosis”), passing through fourstages during its lifetime: egg, larva, pupa,and adult. It is only the last of these, theadult, which we see and recognize as a bee.

During the first three stages, the bee isinside the brood cell of the nest. The eggresembles a tiny white sausage, laid on asupply of nectar and pollen left by themother, and lasts from one to three weeksbefore hatching into a white, soft-bodied,grub-like larva. Whether the egg hatches asa male or female is determined by whetherit is fertilized. Males hatch from unfertilizedeggs and females from fertilized eggs. It isduring the larval stage when most of thegrowth occurs. Feeding on a food supply leftin the cell, the larva grows rapidly for sixor eight weeks before changing into a pupa.

During this apparently dormant stage,which may last eight or nine months, thebee transforms into its adult form within a protective cocoon. When they emergefrom this, the adult bees are fully-grownand ready to mate and continue the cycle.Most adults are active for three or fourweeks, the females working hard to makeand supply a series of egg cells for the next generation.

Bees can be divided into two groups by theirlifestyles: social or solitary. Despite the factthat the popular image is of a bee living ina hive, only a very few species of bees aresocial. Social bees live in a colonial nest,have contact between generations, and sharethe work of building the nest, caring forthe offspring, and foraging for pollen andnectar. The truly social bees in the U.S. arethe non-native European honey bee and thebumble bees (about forty-five species). Ingeneral, the rest of the nearly four thousandspecies of bees in the U.S. are solitary nesting.They create and provision a nest on their


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own, without cooperation with other bees.Although they often will nest together ingreat numbers when a good nesting area isfound, the bees are only sharing a goodnesting site and not cooperating. Inevitably,there are exceptions that prove the rule: a few “solitary” species are known to sharea nest, share the work inside the nest, oreven, in the case of large carpenter bees,have contact between the mother and heroffspring. These are grouped as solitary beesas, quite literally, there are only a handfulof bees in a nest and none of the rigidcolony structure of the social bees.

Solitary nesting bees

Solitary bees generally live for about a year,although we normally only see the activeadult stage of its life, which usually lastsfor only three or four weeks. These creaturesspent the previous eleven months growingthrough the egg, larva, and pupa stage inthe brood cell or nest.

During its brief adult life, the bee is focusedon successful reproduction. The male beewill hang around nesting areas or foragingsites hoping to mate with a female. Thefemale bee will mate once — she stores thesperm and releases it when needed — andthen spends her time creating and provi-sioning a nest in which to lay her eggs.Female native bees have amazing engineer-ing skills, and go to extraordinary lengthsto construct a secure nest. In natural condi-tions, solitary bees will nest in all sorts ofplaces. A few species construct domed nestsout of mud, plant resins, saps, or gumsalong with tiny pebbles on the surface ofrocks or trees. Others will even use emptysnail shells. About a third of bees use aban-doned beetle burrows or other tunnels insnags (i.e., dead or dying standing trees) orexcavate their nests within the soft centralpith of stems and twigs. Most species, how-ever, nest in the ground, digging a tunnelin bare or partially vegetated, well-drained

soil. Sadly, a human desire for tidinessoften means snags are removed and baresoil is covered, resulting in the loss of theseand other suitable nesting places.

Each bee nest usually has several separatebrood cells in which the female will lay hereggs. The number of cells varies accordingto the species. Some nests may have only asingle cell, but most have more, often tenor more and, occasionally, in excess of sixty.These cells may be in a single line filling thehole or burrow, but many ground-nestingspecies dig complex, multi-chambered tunnels. Most species line the cell to protectthe developing bee, sometimes with apolymer-like secretion, but often the interioris just made smooth by the bee. The beesthat make cells in lines typically nest inholes in plants or trees, and use a cap ofplant materials or soil to close each cell andseparate one cell from the next. For example,leafcutter bees neatly trim leaf pieces frombroad-leaved plants and use them to linetheir brood cells, cutting different sizesand shapes for different parts of the cells.Mason bees typically use mud or leaf pulpto seal their nests.

Before she closes each cell, the bee mustprovision it with food for her offspring. Shemixes together the nectar and pollen shecollects to form a loaf of “bee bread,” whichshe places inside the brood cell. She thenlays an egg in the cell, usually on the loaf,and seals the cell. When she has completedand sealed all the cells in her nest, the beewill cap the nest entrance and leave. Afterthe eggs hatch, each larva feeds on the beebread inside its cell until it changes into apupa. After a period of inactivity, it willfinally emerge as an adult and begin thecycle again.

To get the food back to the nest, most beescarry nectar in their crop (a special sac-likechamber in their digestive canal), but howthey carry the pollen depends upon the


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species. Most solitary bees have an area ofstiff hairs, called a pollen brush or scopa,into which pollen grains are pushed. Thesehairs are located either on the underside ofthe abdomen or along the hind legs. In afew species the scopa extend from theirlegs onto their bodies. A few species don’thave scopa and carry pollen in their crop,probably alternating between pollen andnectar on separate foraging trips.

Solitary bees can be divided into two loosegroups according to their foraging habits:generalists and specialists. Generalists arebees that gather nectar and pollen from awide range of flower types and species.Often these are the more resilient species,able to survive in degraded environmentswith weedy or non-native plants. Specialists,on the other hand, rely on a single plantspecies or a closely related group of plantsfor pollen (they are usually less choosyabout sources of nectar), and are more sus-ceptible to landscape or habitat changes.The life cycle of these bees species are oftenclosely tied to their host plant, and theadults will often emerge from their broodcells just when the plant is flowering.

Bumble bees

Bumble bees are the only bees native to the U.S. that are truly social. They live incolonies, share the work, and have multiple,overlapping generations through the spring,summer, and fall. However, unlike honeybees, the bumble bee colony is seasonal.At the end of the summer most of the beesdie, leaving only a few fertilized queensfrom each nest to hibernate through thewinter. In the spring, each surviving queenwill found a new nest that eventually maygrow to include dozens of individuals, occa-sionally a couple of hundred.

Bumble bees need a cavity in which to nest.The queens are opportunists, looking for anysuitably sized cavity. Sometimes this is aboveground, such as in hollow trees or walls, or

under a tussock of grass, but mostly theynest underground. An abandoned rodenthole is a favorite, as this space is warm andalready lined with fur. The queen createsthe first few brood cells from wax, layseggs, and then provisions them with pollenand nectar as the larvae develop. It will

take at least a month for her to raise thefirst brood. When they emerge, these beesbecome workers. They take on the task offoraging and help the queen tend the grow-ing number of brood cells. The workersmay live for a couple of months. The queenwill continue to lay eggs, so the colony willgrow steadily through the summer. At theend of summer, new queens and droneswill emerge and mate. As the cooler weath-er of fall arrives most of the bees, includingthe old queen, will die, leaving only thenew, mated queens to overwinter.

They are generalist feeders, often the firstbees active in late winter (February) and thelast in fall (November). To support a colonyall season, they must be able to forage on awide range of plant species, in a wide rangeof weather conditions. Some individualbees in the colony, however, choose to forageexclusively on a single species or a limitedrange of related plant species, effectivelybecoming specialist foragers. When foraging,the female bumble bee carries pollen in a


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A harbinger of spring inthe western UnitedStates, yellow-facedbumble bee (Bombusvosnesenskii) queensemerge from hibernationwhen willows flower.

concave, hairless area surrounded by stiffhairs on her rear legs, known as the pollenbasket or corbicula. This basket can be seenclearly when it is empty and, when full, thepollen ball pressed into it is obvious.

Bumble bees also differ from solitary beeswhen feeding their larvae. They provide foodgradually, adding it to the brood cells as thelarvae need it (“progressive provisioning”)rather than leaving all the food in the cellbefore laying the egg. In addition, bumblebees do make a small amount of honey, justenough to feed the larvae and themselvesfor a couple of days during bad weather.

Cuckoo bees

A number of bee species do not make theirown nest and, instead, lay their eggs in cellsprepared by another species of solitary orbumble bee. These cuckoo bees are not trueparasites, as they do not feed on the hostbee — although they do kill the larva in thecell, so they can get all the food — but clep-toparasites, as they grow from egg to adultby feeding on the provisions provided bythe host species.

Typically, cuckoo bees that prey on solitarybees enter the nest to lay eggs while the hostis out foraging. Cleptoparasites of bumblebees, however, have to enter an establishedcolony full of workers. Sometimes they willfight to the death with the existing queenand sometimes they’ll hide in the nest untilthey take on the same smell as the hostcolony. Once accepted by the colony theinvading cuckoo bumble bee will take overthe role of queen, laying eggs which theworkers tend.

Helping the ForgottenPollinatorsSympathetic management of out-of-playareas can provide excellent habitat that willbenefit pollinator insects, as well as manyother types of wildlife, and it is these areas

of golf courses that these guidelines arefocused on. Of course, if there are otherplaces on your course that could be suitablefor pollinator conservation, the informationpresented here will help, too. There are several features of golf courses that makethem good for habitat creation and manage-ment, not the least of which is that theyare relatively undisturbed. They also havefull-time maintenance staff, some resources,and a significant acreage of land that ismostly protected from development andother intrusions.

There are three simple things that can bedone to improve golf courses, or indeed anygreenspace, for native bees and other polli-nator insects. Good native bee habitat has two necessary components:

• foraging habitat with a range of nativeplants to provide nectar and pollenthrough the seasons, and


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Two things that bees need are flowers for nectar andpollen and nesting sites, like the asters and thewooden block shown here.

• nesting sites with suitable ground condi-tions or lumber, and appropriate nestingmaterials.

The third step is to avoid using pesticides.Insecticides directly kill bees and herbi-cides kill plants, reducing the diversity offoraging habitat available. It is unlikelythat pesticides will be used in out-of-playareas, though there may be some limiteduse during the establishment of new polli-nator-friendly plants. Wherever possible,use an alternative technique to controlcompetitive plants in pollinator habitat.

By simply adding native plants to out-of-playareas you will help local pollinator popula-tions. Butterflies, flower flies, and otherbeneficial insects (such as nectar-feedingbeetles) will forage in the same habitat asbees. But for native bees to benefit fully, bothforaging plants and nesting sites should becreated. Bees, like butterflies, need differentconditions as adults and young. An adultbutterfly, for example, will sip nectar fromalmost any flower, whereas the caterpillarneeds the right plant to munch on, and isoften very specific about the species.Similarly, with bees, the adult feeds andforages on flowers but it also needs a suit-able place to make a nest in which the larvaewill develop.

These guidelines have been written to helpyou plan and manage out-of-play areas forbeneficial, pollinating insects. They do notattempt to give great detail about specificsof plant care, as many excellent sources ofinformation are already available. In addi-tion, every golf course has different soils orclimate, unique growing conditions thatthe staff will understand better than any-body else.

Managing sites for native bees should notbe confused with beekeeping: there are nohives, no need for special safety equipment,and there is no reason to handle any bees(although you can safely hold nesting

blocks for native bees without any risk ofbeing stung). Creating habitat for nativebees is just a case of ensuring the rightflowers and nesting conditions are there.After that you can sit back and watch thebees work!

Creating Foraging HabitatIn some ways, the ideal approach to creatinga natural area is simply to leave it aloneand let Nature do her stuff. This tactic canwork well in places where there is a neigh-boring source of appropriate seed, andenough time. In most situations, however,you will need to use plants or seed to create

the foraging habitat pollinators need.Growing a native plant is like growing anyother plant: it will need to be planted, andthen require watering and weed control.Since it should be well adapted, a nativeplant is often better able to cope with theconditions and requires less care than anon-native species.

Choosing the Right Flowers

Foraging habitat should contain a range ofplants that will provide a succession offlowers, and thus pollen and nectar, through


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Flower-rich areas will provide nectar and pollen for a wide range of beneficial insects.

the whole growing season. Foraging plantscan be introduced to a golf course by creatingeither natural habitat in out-of-play areasor flower borders in more formal parts ofthe course, such as by the club house orgolf shop. Native plants are frequently thebest choice for both of these approaches, as they are usually better adapted to growin the climate and soils of your region. Inaddition, there are many garden plantsthat are North American natives, such asblack-eyed Susan, Joe-pye weed, and coreopsis,which are wonderful pollinator plants.They may not be native to your region, butmixed with garden plants — particularlyolder varieties of perennials and herbs that are good sources of nectar or pollen —

these can be used to create attractiveflower borders. Such non-native plantsshould not be used in out-of-play areas, asthey can be invasive and cause problems innatural areas.

In a publication of this length it is not possible to give detailed regional lists ofsuitable plants. Included are two lists ofpollinator-friendly plants. Table 1 listsnative plant genera and table 2 garden

plants, both native and non-native. Usedwith the notes below, they will help youchoose appropriate plants. A native plantfield guide to will tell you which speciesfrom these genera in table 1 occur in yourlocale. Your local chapter of the NativePlant Society, county office of the stateCooperative Extension Service, and nativeplant nurseries are worthwhile contacts foradvice on choosing, obtaining, and caringfor local plant species. Most are happy toadvise on all aspects of designing andplanting enhancement schemes. Some citycouncils have lists of plants native to theirarea or botanists who can advise you. Yourlocal telephone directory will list contactsfor most of these, or check the web site ofthe Lady Bird Wildflower Center (see thelist of organizations in appendix B), whereyou will find state-by-state listings of wild-flower organizations and other resources.

When you are planning habitat enhance-ments, the main points to consider are:

• Use local native plants. Local native plantsare usually well adapted to your growingconditions, can thrive with minimumattention, and are good sources of nectarand pollen for native bees. Horticulturalvarieties and hybrids, in contrast, are notnecessarily suited to local conditions, andmay have been bred to produce showyblooms at the expense of nectar or pollenproduction. When obtaining nativespecies, always ask where the seed origi-nates. Often plants sold as native are notfrom local sources, and thus may not giveyou the full benefits of easy growing andpollinator forage.

• Choose plants with a diversity of color.Bees have good color vision and can seeas wide a range of colors as people. Thedifference is that bees see in a spectrumshifted towards blues and ultraviolet, i.e.,we see from red through orange and therest of the rainbow to violet, and bees seefrom orange through the rainbow to violet


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Bumble bees are generalist foragers, visiting a wide range of flowers to feed andgather nectar and pollen. This Sonoran bumble bee (Bombus sonorus) is foraging onstick-leaf blazing star (Mentzelia pumida).

and then into ultraviolet. To a bee, whatwe see as red appears black. In practicalterms, this means that for bees good flowercolors are blue, purple, violet, white, andyellow. (Red will attract butterflies andhummingbirds.) Since we cannot seeultraviolet, we cannot choose UV flowers,though many flowers have UV markingsthat help guide bees to the nectar.

• Choose flowers of different shapes. Beespecies are all different sizes, have differenttongue lengths, and, consequently, willfeed on different shaped flowers. There isa rough correlation between the depth ofthe flower tube and the length of thetongue of the bees that use them. Someflowers, like aster, are very open and thenectar and pollen is readily accessible toinsects of all sizes or those with shorttongues. Others, like lupines and penste-mons, have nectar that is harder to reachand are preferred by robust bees that canpush between the petals or those withlonger tongues. A range of flower shapesmeans more bees (and other insects) willbe supported.

• Have plants flowering all season. Mostbee species are generalists, so a diversityof plants provides a supply of nectar andpollen through their life cycle. Bees canbe seen anytime between February andNovember — maybe longer in mild climates— so a sequence of plants providing adiversity of flowers through the growingseason will support a range of bee specieswith different flight periods. The social-living bumble bees may be out foragingall season, whereas the emergence andactive life of many solitary-nesting bees issynchronized with the flowering periodof forage plants. The active season for beesis influenced by the climate, and so willvary from region to region. For example,in deserts, it is primarily linked to rainyseasons when the flowers bloom, and inmountains, to rising spring temperatures

so it is warm enough for bees to fly. Ingeneral, when flowers are naturallyblooming, bees will be active.

• Include both perennials and annuals.Given the huge diversity of native bees, itis not surprising that there are some thatprefer foraging on perennials and othersthat prefer annuals. Research shows thatsome families of bees tend to forage moreon one type or the other. The small, short-tongued andrenid bees, for example, takenectar mostly from annuals, the colletidbees will forage on either, and the large,long-tongued anthophorid bees and bumble bees forage mainly on perennials.Including both annuals and perennialsin your choice of plants will thus supportmore bees.

• Look at the likely habitat area. The envi-ronmental conditions of the chosen habitat area will influence the choice of plants. It is obvious that sun-lovingprairie plants will not like being plantedin the shade of trees, nor will shade-dwelling forest plants thrive in the sunnyexposure of a prairie, but it is often lessobvious when small-scale changes insoils, slope, exposure, and moisture havesignificant impacts on what will grow.One principle to keep in mind is that aplant community designed to suit existingsite conditions should be simpler andless expensive to establish and maintainthan changing the local conditions tosuit a plant community.

• What is growing already? A survey of wildplants growing in similar conditions canbe valuable for planning, especially if thearea contains original vegetation. Thiswill guide you to which plants are localand indicate plants suitable elsewhere onyour course.

• Growth habit. How large, how spiky, orhow dense the plants grow may also be afactor in which plants to chose. The course


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should remain playable. Some nativeplants may be considered inappropriateas they can interrupt the game (forexample, thorny plants may not be goodif players have to walk through an area to search for stray balls). Similarly, denseground cover can make lost balls harderto find. The solution could be to restrictsuch plants to out-of-play areas, andintroduce golfer-compatible plants else-where. (Or restrict players from enteringpollinator habitat.)

• Avoid invasive species. Species that areknown to be highly competitive, stronggrowing plants, or those that spreadquickly and easily from seed, suckers, or rhizomes should be avoided. They arelikely to spread and dominate the otherspecies, reduce the diversity and value of the habitat, and increase maintenancedemands. They also may spread beyondthe habitat patches and cause problemselsewhere on the golf course. Check withyour local city, as some have code restric-tions on certain noxious weed species.

• Avoid rare species. There is often a goodreason for a species being rare, such asvery specific conditions for establishmentor a particular habitat requirement (orno pollinators!), which will make themdifficult to grow. Of course, if you believeyou can provide the greater managementinput or specialist knowledge for rareplants to survive on your golf course,then consider planting them.

• Think ahead to what the habitat willlook like in the future. Planning five orten years ahead will help guide plantchoices, as it will allow you to considerthe likely maintenance.

Table 1. Native plants for bees and otherpollinator insects.

The plant genera listed below are all goodsources of nectar and/or pollen. Talk toyour Native Plant Society or a native plantnursery in your local area to identify

species from these genera appropriate foryour region.

(Note: This list covers genera from all regionsof the country, so some of the named generamay not be native to or grow successfully inyour area.)


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Common name Genus

yarrow Achillea

giant-hyssop Agastache

wild onion Allium

aster Aster

Oregon grape Berberis

brodiaea Brodiaea

rabbit-brush Chrysothamnus

clarkia Clarkia

shooting star Dodecathon

buckwheat Eriogonum

blanket-flower Gaillardia

geranium Geranium

avens Geum

gilia Gilia

sunflower Helianthus

flax Linum

lomatium Lomatium

lupine Lupinus

evening-primrose Oenothera

cholla (prickly pear) Opuntia

penstemon Penstemon

phacelia Phacelia

currant, gooseberry Ribes

wild rose Rosa

willow Salix

skullcap Scutellaria

stonecrop Sedum

groundsel Senecio

goldenrod Solidago

globe-mallow Sphaeralcea

snowberry Symphoricarpos

mullein Verbascum

Table 2: Garden plants for bees and otherpollinator insects

This list of garden plants includes someNorth American native plants. These wouldbe suitable for flower borders, but not forinclusion in areas of native habitat, exceptin the areas within their natural distribution.When choosing plants, avoid varieties thatare improved or hybrids. Often these havebeen bred for the size or color of flowers atthe expense of nectar or pollen production.

Where to plant

Encouraging more bees and other pollinatorinsects onto your golf course by creatinghabitat will not increase the risk of golfersbeing stung. Despite this, there often willbe resistance to the creation of bee habitat.Fortunately, the chance of conflict betweenplayers and bees is low, as many places on agolf course where people usually go areunlikely to be appropriate for bee conserva-tion. When planning habitat improvementsa survey of the golf course and time spentwatching golfers to see where they mostfrequently go will identify suitable sites.Here are some things to consider duringthis process:

• Playing areas. The principal playing areasare obvious places that are inappropriatefor active pollinator conservation. Tees,greens, and fairways are all managedcarefully to provide specific conditionsfor different aspects of the golf game,creating a landscape that is unlikely toattract many pollinators. Consider usingroughs and out-of-play areas to encouragepollinating insects.

• Course layout. The layout of the courseand slope of the fairways may mean someroughs or out-of-play areas are more likelyto have balls hit into them. (For example,the outside of a bend in the fairway, theinside edge of a dog leg, or the lower sidewhen a fairway has a cross slope.) Theseareas may be suitable for pollinator plant-ings from an ecological perspective.However, because they will have moregolfers walking or driving through themto find and play their balls, they are likelyto become a point of concern to golfersand, thus, may not be appropriate sitesfor planting bee forage.

• Topography. Topography influences the habitat by changing drainage rates, moisture levels, sun aspect, and windexposure. For instance, south-facingareas are usually warmer, creating better


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Common name Genus

giant hyssop Agastache

borage Borago

paint brush Castilleja

wild lilac Ceanothus

bee plant Cleome

cosmos Cosmos

globe thistle Echinops

wallflower Erysimum

Joe-pye weed Eupatorium

blanket flower Gaillardia

sunflower Helianthus

hyssop Hyssopus

English lavender Lavandula

purple gay-feather Liatris

purple toadflax Linaria

mint Mentha

four o’clock Mirabilis

bergamot (bee balm) Monarda

basil Ocimum

marjoram Origanum

poppy Papaver

rosemary Rosmarinus

sage Salvia

skullcap Scutellaria

thyme Thymus

mullein Verbascum

verbena Verbena

zinnia Zinnia

foraging conditions for sun-loving bees.Similarly, drier, warmer places are oftenpreferred by ground nesting bees. Duringrainfall check the drainage of potentialhabitat areas, noting where runoff collectsor flooding occurs. If you already have anarea in mind for enhancement, markwhich parts flood or saturate, and whichare well-drained or stay dry.

• Existing habitat. Look for existing areasof good habitat, as these patches are likelyto support pollinators already. The pollina-tors will benefit directly and swiftly fromexpanding or enhancing these habitatpatches, linking them to other patches,or changing the management regime ofadjacent areas.

• Location of trees. The presence of trees canhave two effects: creating shade and actingas a windbreak. In hot areas shade isunlikely to be a major issue, though you’llwant to avoid places that are shaded in themorning for nesting habitat. Trees as awindbreak can improve a foraging area.

• Size of habitat patches. There is no simpleanswer to how big the habitat patchshould be. The best advice is to makehabitat patches as big as possible, and

create as many as you can. Foraginghabits of many bee species have not beenstudied, and it is not known for sure howbig their home range needs to be. Somebee species have been recorded going nomore than a couple of yards from theirnest to gather nectar and pollen, othershalf a mile or more. Most probably travelless than a hundred yards from their nests.Bigger patches will generally be better forwildlife, providing a site that is morelikely to support stable plant and animalcommunities. For bees, bigger patchesare definitely better as they offer a betterchance that there will be both sufficientforaging plants and a nesting site.

• Shape of habitat patches. Whilst anyhabitat area can be beneficial, the lessdisturbed it is the better. Narrow or linearareas will be more disturbed, as activitiesat the margins (for example, from mowingadjacent grass or players moving betweenholes) will impact proportionately more ofthe habitat. Big and blocky shaped patchesare a good idea, giving the maximumhabitat area for the minimum edge length.

• Habitat corridors. Fragmentation ofhabitats has been a significant problemin recent decades, so where possible, linkhabitat patches with continuous strips ofnatural vegetation. Joining patchestogether will increase their effective sizeby allowing wildlife to move safelybetween individual patches.

• Accessibility of habitat areas. The habitatareas must be accessible for planting andmaintenance. Although in the long termmaintenance should be minimal, in theestablishment period access will be need-ed to provide weed control and irrigation(although irrigation can be reduced byusing locally native plants).

• Visibility of the habitat. On some courses,not all golfers will appreciate having ahabitat area in a prominent location. To


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Many courses already contain good habitat, which can form the basis for a networkof pollinator areas across the course.

some a flower-rich prairie is a beautifulsight, to others it is an untidy eyesore.However, ensuring that the habitat is visible to players also advertises the factthat the course managers have a commit-ment to a healthy environment and that caring for it is an integral part ofcourse management. Habitat areas canbe of great educational or interpretivevalue, giving an opportunity to informplayers how the course is managed andhighlight the benefits gained fromwildlife management.

• Rare plants or wildlife. If you already haverare or unusual wildlife on your coursebe wary of modifying its habitat. Forexample, unless the ecological require-ments of rare plants are understood andcan be assured after any managementaction, altering the habitat could jeopard-ize their survival. This applies also to rareanimals, as altering the habitat (i.e., plantcommunities) they rely upon for foodand shelter might affect their continuedpresence on the course. Additionally,there may be regulations or legislationthat protects both rare species and theirhabitat. In short, be careful when dealingwith the habitat of rare plants or wildlife.

What to plant?

When you have decided which species toplant, the next step is to decide how manyplants you’ll need and what type of plantingmaterial to use, pot-grown transplants orseeds. It is likely that in most situations youwill be adding plants into existing vegeta-tion. For this, pot-grown transplants are farbetter, as they are better able to survivecompetition from existing plants and youwill get a much higher survival rate. Seeds,in contrast, are much more difficult tointroduce into existing grassland, as thecurrent plants will out-compete theseedlings, and are best used on the bareground of new or remodeled golf courses.

Sometimes, you may only be able to getseeds for the species you want. If this is thecase, it may be best to plant the seeds inpots and grow your own transplants.

Occasionally, alternative sources of plantingmaterial are available. For example, if anearby area of habitat similar to the golfcourse environment is being lost to develop-ment, removal of natural sod or plants maybe possible. Translocation of plant materialshas mixed success and, often, the relocatedplants die. Habitat is damaged by theremoval of plants or sod, so it should notbe considered unless the donor habitat isgoing to be destroyed and this is the only waythat fragments can be saved. The creationand management of habitat on golf coursesshould be done in addition to, and not atthe expense of, existing areas.

Deciding how many plants

Calculating how much grass seed to use isa well established and tabulated decision-making process, but deciding how manynative plants to use is less straight forward.The ideal outcome is to have enough plantsto create a self-sustaining plant community.In the short-term, there may be losses dueto poor planting or a lack of watering. In the medium-term, animals like rabbitsor snails might eat them. In the long-term,a small or isolated population could lead toa loss of genetic diversity, a weakening ofthe plant community, or even loss of allthe plants.

• Minimum population size. The ideal targetis to establish a native plant communitythat has enough individuals of eachspecies to be self-sustaining, with eachspecies producing sufficient seed toensure the future of the community. Insimple terms, if the species is perennialthen you will need a smaller number ofplants than if it is an annual. Researchsuggests that the minimum populationneeded to ensure a stable plant community


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ranges from as few as fifty plants for someherbaceous perennials, to several hundredfor some annuals. In your habitat areasyou may not be able to achieve these“ideal” numbers, but try to establish asmany plants as possible.

• Planting density. The choice of transplantsor seeds will influence how much plantmaterial you will need. With transplants,plan for one perennial every 18 incheswithin the habitat area (approximatelyfour plants for every square yard of habitat)and annuals at a higher density of oneevery 12 inches (nine plants per squareyard). Sowing flower seeds on bare soilwill require a much higher density ofbetween five and ten flower seeds persquare foot (up to ninety seeds per squareyard) for each species, mixed in withnative grass seeds. (See pages 17–18 formore information.)

• Distribution. These plant populations donot necessarily have to be in a singlehabitat patch. If habitat areas are not toofar apart (less than about 50 yards), popu-lations of plants can be spread betweentwo or three patches. Perennials, whichlive for several years and are able to copewith changing conditions, are more likelyto thrive with a divided population.Annuals, in contrast, need to create seedfor the next generation of plants withinthe first summer. To ensure adequate pollination between plants, the popula-tions should be close together.

Establishing and Growing Pot-grownTransplants

Pot-grown transplants are the most suitableplanting material to use when addingplants to existing vegetation. The followingsuggestions will help you achieve higherplant survival rates:

• When to plant. In most areas, perennialscan be planted during the fall or spring.

Desert areas may be different, as therainfall seasons will dictate the best timefor planting. In general, fall planting isbetter, particularly for spring-floweringspecies. This gives time for roots to getestablished before the growing season andwill make plants more resilient to drysummer conditions, reducing the needfor supplemental irrigation. In regionswith long, cold winters, however, springplanting may be better, as frost heavemay push plants out of the ground. Thenatural rainfall pattern in your regionwill also influence planting time. Planplanting so the transplants will benefitmost from the available rainfall.

• Site preparation. Remove the worst weeds.Areas of bare soil may create a bad weedsituation for the future, so avoid clearingall vegetation. The advantage of usingtransplants is that they can be introducedinto an existing vegetation cover, whichhelps to suppress weeds.

• Planting pattern. Assuming you wish to create a natural-looking area, avoid planting on a strictly measured grid with regular spacing and straight lines.Distribute the plant species randomlyacross the habitat area, planting clumpsof individual species containing five orsix plants.

• Irrigation. Adequate water during the firstsummer is critical. Planting in fall willreduce the need for irrigation, as theplants will have had time to develop larger,deeper root systems, which are betterable to survive the first summer withoutirrigation. Irrigation, especially sprinklersystems that wet the surface, will benefitweeds too, so minimizing the need forirrigation will also help to reduce weedproblems. When planting annuals orspring-planted perennials, a general guideis to irrigate at least once a week for thefirst six weeks. After that, water as needed.These guidelines are not region-specific and


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irrigation regimes will need to be adaptedto local soil, topography, and climate.Mulching the soil surface in the first yearafter planting can help to retain moistureand reduce the need for irrigation.Irrigation of perennials in subsequentyears should not be necessary — unless adrought is going to kill the plants — asthis additional water can encourage rootdevelopment close to the surface, makingthe plants more susceptible to damage bydry spells, and impede the growth of thedeep roots the plants need.

• Weed control. Weeds compete for light,nutrients, and water, and will stunt oreven kill desirable plants. Lack of weedcontrol is one of the most common factorscausing poor establishment of plantings.Mulching the newly planted area willhelp to suppress the growth of unwantedplants, but is unlikely to provide completeweed control. Herbicides may damagethe transplants. The only effective method

may be to hand weed around the trans-plants, pulling up perennial weeds andpulling or cutting annuals before they go to seed. Waiting until annuals areflowering before weeding can be effec-tive, as plants have put all their energyinto growing and flowering, and mayhave little time or energy left to re-grow.

Using wildflower seed

The creation of wildflower-rich grassland iseasily integrated into course constructionor remodeling. This can cheaply and swiftlyproduce large areas of species-rich turf. The points below will guide you when doingthis. This approach may also be used togrow species-rich sod, very much as youmight grow turf in a putting green nursery,ready for transfer into the habitat areas.Once in place, it will provide a reservoir ofnative plants that can spread through thesurrounding area, although this can be aslow process.

• Seed mix. Natural prairies often havedozens of species, but for a new area a seedmix containing fifteen to twenty speciesof native grasses and forbs will be enough.Between 50 and 80 percent of the volumeof the seed mix should be made up of fouror five species of native grasses, whichcould include a fast-growing annualspecies as a nurse crop. A seed mix ofthis diversity will give a good foundationfrom which a richer habitat can developthrough natural colonization or enhance-ment with transplants in future years.Choose forb species that will give a rangeof flowering times through the seasons,and a variety of flower colors and shapes.Your native plant seed provider or NativePlant Society chapter can probably adviseyou on which species and how manyseeds you’ll need.

• Site preparation. The seedbed should betilled and treated for weeds. If the site isprone to erosion, soil conservation measuresshould be incorporated into the plan. Soilprotecting polymers or straw mulch canbe added after seeding to stabilize the soil.If the site is near a water body, erosionfences to stop soil washing into the watermay be required by local environmentalcodes, and should certainly be installed asa matter of good practice.


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Irrigation and weed control are the two most importantmaintenance tasks for newly planted areas.

• Seeding. The actual method of seedingwill depend on a number of factors,including site location, topography, andsize. For small areas, broadcasting byhand is often the best, and simplest,method. For larger areas a seed drill orhydro-seeding may be necessary. Afterseeding, rake or harrow the area.

• Irrigation. As with transplants, irrigationof seeded areas is vital during the firstsummer.

• Weed control. Weed control may berequired for two or three years depend-ing on the rate of establishment andgrowth of the newly planted seeds. Oncethe new species-rich turf is established itshould be dense enough to suppressannual weeds, though some regularmaintenance will be needed to controlnoxious or invasive species.

Habitat management

Depending on the type of vegetation com-munity created, you may have to undertakemanagement of the habitat areas. In manyareas, untended prairie plant communitiesleft will develop into scrub or forest if theyare not cut or burned periodically to main-tain the open, sunny conditions. If the areais cut, the cuttings should be removed.Leaving them on the ground can smotherplants and, over time, will lead to a build-up of nutrients that can favor stronger growing, weedy species instead of the desirednatives, resulting in a loss of diversity.Cutting or pulling unwanted shrubs couldcheck their spread. (Treat the stumps toprevent re-growth.) Don’t cut or burn thewhole area in one go. A wide range ofinsects, including butterflies, beetles, andbees, lay eggs on or overwinter inside plantstems. A two or three year rotation ensuresthat all areas get cut and yet maintainspatches of suitable overwintering habitat.

During the planning stage of the habitatareas thought should be given to what you

want the area to look like in the future (forexample, ten years ahead). With this inmind, plants should be chosen that will besimple to manage and resources should beidentified to support the management ofthese habitats. Conservation and habitatwork may be of interest to golfers, otherlocal volunteers, or scout groups (forinstance, Eagle scouts often need projectsfor badges). These groups should be kept in mind, or approached, when planninghabitat improvements.

Bee nesting sitesThere are several simple ways in whichnesting sites can be made for bees. Here we describe how to make a variety of nesttypes for both ground- and wood-nestingsolitary bees, and bumble bees. Many ofthese methods mimic natural features, suchas beetle-bored snags, patches of bare ground,or old walls that no longer exist in modernlandscapes. As with many aspects of conser-vation, the wider the range of conditionsyou create, the greater the diversity ofspecies you could attract. However, not allnest types described below will be suitablefor your golf course. Walls made fromadobe blocks, for example, may not lastlong in a rainy climate.

Location of the nesting sites is important.Most ground-nesting bee species will avoidwet soil, so choose areas of dry, well-drainedground, preferably south or southeast facing.(Some species line their brood cells with awaterproof membrane, so can nest in ripar-ian areas that flood occasionally.) In damperareas, the addition of sand piles or otherraised soil can dramatically improve theconditions for bee nesting, but not if thesite will have standing water that couldsoak up into the piles. Wood-nesting beesprefer sites that are sheltered from theworst of the weather, with entrance holesfacing towards the east or southeast, sothey get the morning sun. Most bees cannotheat themselves efficiently, and need the


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sunshine, especially in the morning, to provide enough warmth so they canbecome active.

The nesting sites should be in or close toareas of foraging habitat. Many bee speciescannot fly long distances, so will not usenests if they are isolated from foraginghabitat. In addition, if foraging habitat isseparated from nesting sites, bees mayexpend more energy flying than they gain from feeding. If you create the rightconditions, bees will begin to use the nests,often only days after you finish them.

Nesting sites for ground-nesting bees

Most native bees nest in the ground. Therequirements of some species are so wellunderstood that artificial nesting sites arecreated commercially to provide reliablecrop pollination. The alkali bee as a polli-nator of alfalfa is the best known example.For others, the precise conditions to attract

particular species are not known. Themethods outlined below will allow you tocreate ground conditions and establishsites suited to a diversity of species.

• Bare ground. Simply clear the vegetationfrom a small (about 6 feet by 6 feet) level orsloping area, and gently compact the soil.These areas should be well drained, in anopen, sunny place, and, where possible,on a southeast-facing slope. A few rocksplaced in the cleared area will improve it by adding basking places. In addition,these rocks help to warm the soil byabsorbing and retaining the sun’s heatand by reducing air movement, and itsconsequent cooling, along the ground’ssurface. Inevitably, different ground con-ditions — from vertical banks to virtuallyflat ground — will draw different beespecies, so create several different areaswithin your habitat.

• Sandpit. Dig a pit about 12 feet square and3 feet deep, and fill it with fine-grained,pale-colored sand, or a mix of loam andsand. The pit must be able to drain, other-wise the nests could flood. As with areasof bare ground, the sandpits should be insunny places.

• Sand pile. Where soils do not drain well,a sand pile or raised bed (contained bywalls of lumber or bricks) of similar sandor sand/loam mix as the sandpit, but onlyabout 2 feet high, can create suitablenesting conditions.

• Adobe blocks. A wall about 4 feet highand 6 feet long made from adobe blocksalso can provide warm, dry nesting sites.Use wood and/or metal backing and sup-ports to prevent the blocks from toppling.The front of the wall should face towardsthe east or southeast. In this face, drillholes in a range of diameters between3/32 inch and 3/8 inch as deep as you can —at least 4 inches for the larger diameterholes — into the blocks.


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Combining nesting sites with foraging areas will creategood native bee habitat.

Nesting sites for wood-nesting bees

Many bees, such as leafcutters and masons,naturally nest in beetle tunnels in snagsand similar holes. Information about oneof these, the orchard mason bee, is widelyavailable, particularly the size of nestinghole they prefer (5/16 inch diameter). Thereare many other bees that will nest indrilled holes (including other species ofmason bee), but they prefer other holesizes. When making wooden nest blocks orthe other types of nest described below,providing a range of hole sizes will supporta wider range of bee species that will for-age and pollinate over a longer season thanjust the orchard mason bee, which, in mostareas, is active only between late Marchand early May.

• Logs and snags. Get some logs or oldstumps and place them in sunny areas ofthe habitat patches. Plant a few upright,like dead trees, to ensure some deadwoodhabitat stays dry. On the southeast sideof each log, drill a range of holes, as withthe adobe blocks, between 3/32 inch and3/8 inch diameter and as deep as you can(at least 4 inches deep for the largerdiameter holes). When drilling, make theinterior of the holes as smooth as possible.Bees are not partial to rough holes andmay avoid them.

• Twig bundles. Elderberry stems, withtheir soft central pith, are naturally usedby some bee species, and can easily beused to create nesting sites. Cut the stemsinto 8 inches to 12 inches lengths. Fromone end, drill out the central pith to form

a hole 3/32 inch to 3/8 inchdiameter to a depth ofup to 6 inches, ensur-ing that the opposite

end stays closed off. Tiethe stems in bundles of fif-

teen to twenty, and fix the bundle to astake or tree with the stems horizontal tothe ground. Other plants whose stems

have a soft pith or are hollow can be sub-stituted, such as blackberry, raspberry,sumac, bamboo, or teasel. Hollow stemsare really easy, as you only have to cutand tie the bundles. When cutting, becareful to cut close to a stem node. Thiswill leave a tube with one end open andthe other closed.

• Elderberry stakes. Cut elderberry stemsinto stakes, between 24 inches and 30inches long, and sharpen one end tomake it easier to push into the ground.Drill out the pith from the other end, asyou did the stems for the twig bundles,and then about 12 inches from this end,drill a “side hole” of similar diameterthrough the bark just into the pith. Drivethe stakes about 6 inches into the groundin a line across your habitat area.

• Nesting blocks. Bee nesting blocks canbe made from blocks of water-resistantlumber at least 4 inches by 4 inches and8 inches long. Larger lumber sizes — 4 inches by 6 inches, or even 8 inches —

are better as you will be able to drilldeeper holes. Avoid treated lumber, asthe chemicals may affect the nests, andcedar, which has a natural pesticide(hence it being used for closets andchests to give protection from clothesmoths and carpet beetles). In one side ofthe block, drill holes between 3/32 inch


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Make bundles of 15 to20 lengths, with theopen ends facing the

same way, and tie with string, wire, or

duct tape.

This can be done withany hollow stemmed

plant, such as bamboo.

Wooden nesting blocks and other nests for hole-nest-ing bees can be made in different sizes and styles.

and 3/8 inch in diameter, at approximate3/4 inch centers. The holes need to beclosed at one end, so either drill almostall the way through the block to leave awall, or drill all the way through andthen back the block with wood. Whendrilling, make the interior of the holesare smooth as possible. The block can beas simple or fancy as you like. A roughblock of lumber will work OK, as willholes drilled in a dead tree, or you canattach the block to a backing board andfix a sloping roof, painted in attractivecolors. The roof should extend beyond thefront of the block to afford the nestingholes some protection from rain, hail,and snow. The block can be fixed to astake, fence, or building, or placed in atree, in a sunny, east or southeastwardfacing spot. It needs to be fixed firmly soit doesn’t shake in the wind.

Bumble bee nests

Unlike solitary bees — who can be very par-ticular about hole diameters — bumblebees are more flexible in their nestingneeds. All they are looking for is a dry,warm hole of a suitable size. There are no

strict requirements for this, but there aresome general guidelines. The nest shouldbe weatherproof and well insulated (thegrowth of the larvae can be stunted if thenest gets too cold or, in particular, too wet).Bumble bees prefer a nest with two cham-bers, one as the brood chamber where theywill make the nest and one as an entrance.The entrance hole should be no more than3/4 inch in diameter, marked on the out-side with a contrasting color, and providedwith a landing platform. Finally, the nest-ing chamber needs to contain insulatingmaterial, such as upholsterer’s cotton orunraveled, soft string.

You can use any lumber you have availableand adapt the dimensions to suit the mate-rials you have. Do not use treated lumber,as the chemicals may affect the bees — thetreatment, after all, is intended to protectthe lumber from insects. The lumber usedwill be able to cope with the weather forseveral years, so there’s no need to paint it.The important things are to make the jointsand cracks weather tight with caulking orsimilar and to have a roof that will keepthe rain out.

A good size for a nest is a box about 16inches long, 8 inches wide, and 7 inchesdeep, with a floor that extends at the frontto form a landing platform and roof thatoverhangs on all sides. Through each end,drill a cluster of small-diameter ventilationholes, and cover them with door screeningto deter ants. Inside, the two chambersshould be different sizes; the brood chamberabout 71/2 inches long and the entrancechamber about 51/2 inches long, divided bya piece of 2 by 4 laid on edge across thebottom of the box. (Drill a 3/4 inch holethrough this to allow the bees to passbetween chambers, although they will alsobe able to climb over the divider.) The actualnest entrance is made by a length of 3/4 inchplastic pipe that goes through the frontwall close to the floor and extends into the


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Fix a pitched roofto shelter nest

from rain.

Distance betweencenter of holesapprox. 3/4''.

Drill as far into the block as you can, leaving theback of the hole closed. The holes should bebetween 3/8'' and 3/32'' diameter. A range ofsizes will attract a range of bees. The holes do notneed to be drilled in any particular pattern.

entrance chamber. Highlight the entranceon the outside with paint or a marker pento help bees find it. Finally, place a smallamount of nesting fiber (upholsterer’s cottonor similar) into the brood chamber beforefitting the roof. The roof can be made froma single piece of plywood or two pieces ofplank glued together, with a drip moldingaround the edges to improve rain resistance.Attach the roof to the top of the nest witha couple of screws, or simply weigh it downwith a few bricks or rocks (enough to deterraccoons). You can make an inner roof ofPlexiglas, so you can lift the wooden roofoccasionally to look inside without disturb-ing the bees.

Place your nest on bricks or lumber spacersto keep it up off the damp ground, with theentrance hole between 4 inches and 10 inchesoff the ground. Choose a site that is undis-turbed, in partial or full shade, where thereis no risk of flooding, and where it is notclose to a known ant colony. Put your nestingbox out when you first notice bumble bees inthe spring, or when the first willows andother flowers are blooming, and be patient.If it has no inhabitants by late July, put thenesting box into storage until next spring.Don’t look inside your nest too often, asbees don’t like disturbance.

ConclusionsSimple changes to the environment of golfcourses can have great benefits for wildlife.Hopefully, these guidelines will help withthe planning and management of habitatfor native pollinator insects, especially bees.A flower-rich habitat for bees may alsobecome home to hummingbirds, butterflies,beetles, and flower flies and other insects,and diverse habitats will attract other animals and birds. In addition to the wildlifebenefits from the habitat, a rich insectfauna can help the golf course, as some ofthe insects attracted will be beneficial inthemselves. Several solitary-nesting wasp

species, for instance, are predators of golfcourse pests, such as cutworm, and willnest alongside the bees in wood nestingblocks or in the ground.

Golf courses offer wonderful opportunitiesfor wildlife conservation. They can containlarge areas of natural vegetation that are relatively undisturbed by people, providingsafe refuge for wildlife as the landscapesaround them come under increasing pres-sure. With a little care and planning theseareas can support a wonderful diversity ofwildlife and add beauty to the golf courselandscape. Habitat areas also offer educa-tional possibilities, not just for the golfersbut also for local schools and communitieswho can learn about practical conservationtechniques and witness first-hand the bene-fits of the golf course. Conservation ofnative bees and plants is a valuable way inwhich golf courses can contribute to ahealthier environment, and is a simple taskto integrate into the management of yourgolf course.


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Appendix A: Bee Stings, andHow to Avoid ThemOne of the major concerns that people haveabout bees is being stung. Certainly it can bepainful but except for a very small numberof people who are affected by anaphylacticshock — a strong allergic reaction — beingstung poses little more threat than discom-fort. (Generally, people know whether theyare affected by anaphylactic shock andcarry an epinephrine kit.)

Memories of being stung are also a situationin which bees and wasps become confused.Wasps are closely related to bees and sharesimilar life cycles and habitats, with somebeing solitary nesters and some — in partic-ular, the yellowjackets and hornets — nestingsocially. One way in which wasps and beesdiffer profoundly is in their diet. Waspsgenerally are predators and scavengers,chasing and killing insects to provision theirnests or eating carrion for food. When theycan, the adult yellowjackets also feed onsweet, sugary food or drink, like rotting fruitand sodas. Because of their predatory habits,wasps have effective, multiple-use stingers.

Bees, in sharp contrast, are completely vegetarian, feeding on nectar and pollen, a floral diet that only needs to be locatedand not subdued. Their stings are only fordefense, and even then they are usuallyreluctant to use them. Bees are capable ofstinging more than once. The honey bee isthe only one that leaves its stinger in thevictim (the bee will die after being eviscer-ated by this, another disincentive to use itssting). Some wasp species are also pollenand nectar feeders, and are as unlikely tosting as most bees.

When foraging, all bees will do their bestto ignore you. Solitary nesting bees will alsogenerally ignore you at nesting sites. Theirsurvival strategy is to flee rather than fight.After all, it is better for a solitary bee toabandon her nest and start again elsewhere

than risk dying to defend it. The social bees — honey bees and bumble bees —might sting to defend their nest if they feelthreatened. Not only do they have a colonyof workers and brood to defend but, in thecase of honey bees, they also have a win-ter’s supply of stored honey to protect.

Bees have highly developed senses to findand locate flowers, and flowers have manyadaptations to make this easier, includingcolorful petals and a scent. Consequently, ifyou look or smell like a flower bees mightbe attracted to you! Bees have good colorvision, seeing a range of colors from orangeto violet and into the ultraviolet. Theyseem to be particularly attracted to flowersthat are white, yellow, and, especially, blueor purple. To reduce the likelihood of beesfinding you, avoid strongly scented or floralperfumes and try not to wear bold floral-pattern clothing or a lot of bright bluewhen on the course.

On the golf course, stay on the marked cartpaths and playing areas. When a ball goesinto the out-of-play habitat areas considerwhether it is worth the search. By doingthis you will be keeping out of areas morelikely to have bees. If you do search for yourball, look carefully and avoid swinging yourclub at vegetation. Inadvertently swipingthe entrance to a wasp or bumble bee neston the ground could aggravate them.

Often, when a player is stung on the courseit is not through malevolence on the part ofthe bee but simply through being caught inclothing or hair. If a bee does fly close toyou, avoid swatting it. Be patient, it will flyaway. If you must encourage it to go away,be gentle, slow, and deliberate in yourmovements, so that you minimize thechance of it getting trapped or feelingthreatened.

Pheromone traps for wasps are widely avail-able from hardware and gardening stores.These may help limit wasps when used in a


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small area like a back yard or deck, but in alarge space such as a golf course they havelimited impact. On a golf course there areso many places beyond your control wherewasps could be coming from that it isalmost impossible to prevent them fromflying around.

Dr. Justin Schmidt, a United StatesDepartment of Agriculture bee stingexpert, has the following advice:

“Stings, though painful and frightening, are usuallyharmless and the intense pain will go away in five to ten minutes, or less. Residual minor pain,followed by redness, swelling, itching and minordiscomfort may continue for several hours. Aftereffects, mainly swelling, might last a day or two. Ifthe culprit is a honey bee, the stinger will be left inthe skin and should be pulled out with fingers orscraped out with a fingernail. The best treatmentfor the immediate pain is the application of a thickpaste of ordinary salt and water to the sting area.This will give relief within a short time. Other homeremedies may also have merit and should not bedangerous, but none have been shown superior tosimple salt. An aspirin might be taken to helpreduce potential swelling.”

Managing out-of-play areas for bees isunlikely to create any greater hazard or discomfort than already exists for golfers.They are more likely to be troubled by theyellow jackets attracted to trash cans, sodas,and turkey sandwiches than by native beesbenefiting from the enhanced forage andnesting habitat.


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Appendix B: Useful resources

Books and Journals

Borror, Donald J., and Richard E. White.1970. A Field Guide to Insects. America North ofMexico. Houghton Mifflin, Boston, MA. (This book will help you to identify insects.)

Buchmann, Stephen L., and Gary PaulNabhan. 1996. The Forgotten Pollinators. IslandPress, Washington, DC. (An overview ofpollinators and conservation issues.)

Dodson, Ronald G. 2000. Managing WildlifeHabitat on Golf Courses. Ann Arbor Press,Chelsea, MI. (A useful guide to managingall types of habitat.)

Harker, Donald, Gary Libby, Kay Harker,Sherri Evans, and Marc Evans. 1999. LandscapeRestoration Handbook. 2nd Edition. LewisPublishers, Boca Raton, FL. (A good guide tohabitat creation, with a region-by-regionoutline of habitats and plant communities.)

Kearns, Carol, and James Thomson. 2001.The Natural History of Bumble Bees. A Sourcebookfor Investigations. University Press of Colorado,Boulder, CO. (A slim, very readable book,that is an excellent introduction to NorthAmerican bumble bees.)

Imes, Rick. 1992. The Practical Entomologist.Fireside Books, New York, NY. (An introduc-tory book that is packed full of practicalentomology information: identification,collection, raising, biology, etc.)

O’Toole, Christopher, and Anthony Raw.1999. Bees of the World. Blandford, London,UK. (A great introduction to bees and theirbiology, behavior, and lifestyle.)

Procter, Michael, Peter Yeo, and AndrewLack. 1996. The Natural History of Pollination.Timber Press, Portland, OR. (An excellentbook, probably the best single volume on pollination. Fairly heavy reading, butstuffed full of information on plant/pollinator relationships.)


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Hortus West. The Native Plant Source Directory.PO Box 2870, Wilsonville, OR 97070. (This isa brilliant reference for plant availabilityand nurseries in the western states.)

Nonprofit Organizations and Companies

The Bee Works. Environmental consultancyengaged in native bee research and conser-vation efforts.

Stephen Buchmann, President

1870 W, Prince Road Suite 16

Tucson, AZ 85705

Tel: (520) 888-7422 Fax: (520) 888-7332

Email: [email protected]

Website: www.thebeeworks.com

BioQuip. Entomological equipment, books,and supplies.

17803 LaSalle Avenue

Gardena, CA 90248-3602

Tel: (310) 324-0620 Fax: (310) 324-7931


Website: www.bioquip.com

Carolina Biological Supply Company. Scienceand educational equipment.

2700 York Road

Burlington, NC 27215

Tel: (800) 334-5551 Fax: (800) 222-7112

Email: check the Web site for

department addresses

Website: www.carolina.com

Lady Bird Johnson Wildflower Center. A nonprofitcenter that is a great resource for nativeplant information. Can supply lists of suit-able plant species for many areas.

4801 La Crosse Avenue

Austin, Texas 78739-1702

Tel: (512) 292-4200 Fax: (512) 292-4627

Website: www.wildflower.org

Internet sites

Information on native bees

www.xerces.org/poll/home.htmInformation on bee conservation, biology, and life cycles.

www.loganbeelab.usu.edu/default.htmSome good information about native bees, and links to other sites.

www.thebeeworks.comContains a lot of information on bees, their conservation, and education ideas.

www.pollinatorparadise.comA site with information on native bees, especially their management.

www.earthlife.net/insectsAmazing site that has innumerable links and is stuffed full of great invertebrate information.

www.mearns.org.uk/mrssmith/bees/bees.htmA site dedicated to bumble bees

Native Plant Society. Divided into state societieswith local chapters. The Web site of theLady Bird Johnston center (see above) listsall the state societies.

North American Pollinator Protection Campaign.A consortium of conservation groups, government agencies, universities, and private industries from the United States,Mexico, and Canada. NAPPC participantsshare information and work together forthe common good of pollinators across ourcontinent.

Website: www.nappc.org

Pollinator Paradise. A company providingconsultancy services and doing research on bee conservation and management for agriculture.

Karen Strickler, President

31140 Circle Drive

Parma, ID 83660

Tel: (208) 722-7808


Web site: www.pollinatorparadise.com

Society for Ecological Restoration. Contact theirnational office for local contacts, or checkout their Web site.

1955 W. Grant Road #150

Tucson, AZ 85745

Tel: (520) 622-5485 Fax: (520) 622-5491


Website: www.ser.org

The Xerces Society. A nonprofit dedicated topreserving the diversity of life through theconservation of invertebrates. It runs edu-cation and conservation projects and pro-duces information materials. Through itsPollinator Conservation Program it offerspractical advice on habitat managementfor pollinator insects.

4828 SE Hawthorne Boulevard,

Portland, OR 97215

Tel: (503) 232-6639 Fax: (503) 233-6794

Website: www.xerces.org


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27

www.ces.ncsu.edu/depts/ent/notes/Other/orn_t109/not109.htmlInformation on orchard mason bees.

dmoz.org/Science/Agriculture/Animals/Invertebrates/Beekeeping/Solitary_Bees/Lots of links to Web sites on pollination and solitary bees.

www.ars.usda.gov/is/AR/archive/may00/buzz0500.htmAn article from the ARS Newsletter about recent research on alternative pollinators.

www.nappc.orgThe North American Pollinator Protection Campaign.

Information on plants and bee nesting sites

www.xerces.org/poll/home.htmPractical conservation advice and links to other Web sites.

www.cae.wisc.edu/~oliphant/bees/bombus/pollination.shtmlSome plants that bumble bees forage from and pollinate, in approximate order of flowering.

members.aol.com/beetools/bumble.htmBuilding nests for bumble bees, mason bees, and soon, leaf cutter bees.

gears.tucson.ars.ag.gov/na/bgardn.htmlAdvice on creating a bee garden or modifying your existing garden to attract native bees.

www.nhq.nrcs.usda.gov/CCS/Backyard.htmlBackyard Conservation: bringing conservation from the countryside to your backyard.

wildflower.avatartech.com/Plants_Online/index2.htmlDatabase of native plants, seed suppliers, and native plant organizations.

www.loganbeelab.usu.edu/default.htmClick the Bees & Gardens link for lists of plants.

www.nwf.org/backyardwildlifehabitatThe NWF Backyard Wildlife Habitat site.

Entomological and educational equipment, materials, and ideas

cvs.anu.edu.au/andy/beye/beyehome.htmlGreat site explaining how bees see objects, including a simulation of bee vision.

members.aol.com/yesbugs/bugclub.htmlYoung Entomologists’ Society.

lamar.colostate.edu/~gec/4Hman/contents.htmThis site contains good education projects and activities, and information on collecting andidentifying insects.

www.ent.iastate.edu/list/A directory and search engine of insect-related Internet resources.


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AcknowledgmentsI would like to thank the U.S. Golf Association and the National Fish and WildlifeFoundation for funding the project work on golf courses, and the staff of the USDA-ARSBee Biology and Systematic Laboratory for their scientific guidance and field work duringthe project, especially Dr. Vince Tepedino. I also thank Kimberly Erusha of the USGA forher encouragement, support, and editing during the production of this guide. The textwas reviewed by Mace Vaughan of the Xerces Society, Angie Kimpo of the City of PortlandWatershed Revegetation Program, and Gabriela Chavarria and Peter Stangel of NFWF.Their comments and insight improved the text considerably. Obviously, any mistakesthat remain, are mine.

Matthew Shepherd is Pollinator Program Director of the Xerces Society, based in Portland, Oregon.Matthew has extensive experience of managing both habitat management and environmentaleducation programs.


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Notes


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Notes

The Xerces Society is a nonprofit organization dedicated to preserving the diversity of life through the conservation of invertebrates. TheSociety works to protect invertebrates and their habitats by producinginformation materials, presenting education activities, implementingconservation projects, and advocacy. Its main programs focus on endangered species, aquatic biomonitoring, and pollinator conservation.

This publication was the result of a research grant provided through the USGA Wildlife Links program. Wildlife Links is a cooperative program with the National Fish and Wildlife Foundation that fundsresearch, management, and education projects to continue to improvethe golf course’s role within the conservation landscape.

The United States Golf AssociationGolf HouseLiberty Corner RoadPO Box 708Far Hills, NJ 07931T 908 234-2300F 908 234-9687www.usga.org

The Xerces Society4828 SE Hawthorne BoulevardPortland, OR 97215T 503 232-6639F 503 233-6794www.xerces.org

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