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June 2, 2017 Issue 2017.5

______________________________________________________________________________ Welcome to the Plant Health Care Report (PHCR). My name is Sharon Yiesla. I am on staff at The Morton Arboretum Plant Clinic, and I am responsible for compiling the newsletter. Comments or concerns regarding PHCR should be sent to syiesla@mortonarb.org. To be added to the email list, please contact me at that email address.

Our report includes up-to-date disease and insect pest reports for northeastern Illinois. You'll also find a table of accumulated growing degree days (GDD) throughout Illinois, precipitation, and plant phenology indicators to help predict pest emergence. This newsletter is available online at http://www.mortonarb.org/news-publication/plant-healthcare-report?tid=259

Quick View What indicator plant is in bloom at the Arboretum? Arrowwood viburnum (Viburnum dentatum) is in early flower (Figure 1) Accumulated Growing Degree Days (Base 50): 419.5 (as of June 1) Accumulated Growing Degree Days (Base 30): 2115.5 (as of June 1) Insects/other pests

Rose plume moth

Rose slug sawfly

Four-lined plant bug

Wooly aphids

More sawflies

Carpenter bees Diseases

Apple scab

Sycamore anthracnose

Powdery mildew on ninebark

Brown rot of stone fruit

Black knot

Viruses Weeds

Poison hemlock

Creeping bellflower

Plant Health Care Report Scouting Report of The Morton Arboretum

Figure 1 Arrowwood viburnum (photo: John Hagstrom)

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Degree Days and Weather Information We are once again offering Lisle readings right above the Arboretum readings. The spread between these two sites shows that temperatures can vary over a short distance, which means growing degree days can be quite variable as well.

As of June 1, we are at 419.5 base-50 growing degree days (GDD). The historical average (1937-2016) for this date is 379 GDD50. Since January 1, we have had 20.94 inches of precipitation. Historical average (1937-2016) for precipitation Jan-May is 13.86 inches.

www.gddtracker.net is not working today. GDD numbers are from May 30, 2017, unless noted otherwise.

Location B50 Growing Degree Days

Through May 30 2017

Precipitation (in)

May 26-June 1, 2017

Carbondale, IL* 1056

Champaign, IL* 754

Chicago Botanic Garden** 386.5 (as of 5/31) .41 inches

Chicago O'Hare* 467

Kankakee, IL* 566

Lisle, IL* 490

The Morton Arboretum 419.5 (as of June 1) .59 inches

Northbrook, IL** 367.5 (as of 5/31)

Quincy, IL* 842

Rockford, IL* 409

Springfield, IL* 796

Waukegan, IL* 329

**Thank you to Mike Brouillard, Northbrook Park District and Chris Beiser, Chicago Botanic Garden, for supplying us with this

information.

*We obtain most of our degree day information from the GDD Tracker from Michigan State University web site. For additional locations and daily degree days, go to http://www.gddtracker.net/

How serious is it? This year, articles will continue to be marked to indicate the severity of the problem. Problems that can

definitely compromise the health of the plant will be marked “serious”. Problems that have the

potential to be serious and which may warrant chemical control measures will be marked “potentially

serious”. Problems that are seldom serious enough for pesticide treatment will be marked “minor”.

Articles that discuss a problem that is seen now, but would be treated with a pesticide at a later date,

will be marked “treat later”. Since we will cover weeds from time to time, we’ll make some categories

for them as well. “Aggressive” will be used for weeds that spread quickly and become a problem and

“dangerous” for weeds that might pose a risk to humans.

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Figure 2 Caterpillar of rose plume moth

Figure 3 Rose slug sawfly larvae and damage

Pest Updates: Insects

Rose plume moth caterpillar (minor)

Rose plume moth caterpillars (Cnaemidophorus rhododactyla) are now at work on roses. This

larva is a caterpillar and is approximately ½ inch long. It

is light green with a reddish stripe running from its head

to the middle of its body at one point in its life cycle (fig.

2). The adults are present June through August. New

larvae are produced in fall and overwinter inside the

stems of the rose. They resume feeding in spring (May).

Plume moth larva has been most commonly found near

the tips of rose bushes, damaging the buds and leaves

and sometimes creating some webbing. The caterpillar’s

color blends with the color of new rose growth nearly

perfectly, so they may be difficult to find. A lot of frass (insect feces) is also found in these

areas.

Management: Pruning off infested tips may be the best management advice that can

be offered at this time. Since this is a caterpillar, Bacillus thurengiensis kurstaki (Btk) should be

effective, but is best used when the caterpillars are small.

Rose slug sawfly (minor)

Rose slug sawfly (Endelomyia aethiops) larvae have also been seen on roses. They feed on the

upper layers of the leaf, leaving behind the lower

epidermal layer and creating a "windowpane" effect. The

larvae are greenish yellow with orange heads and are

about ½ inch long when fully grown. They resemble

caterpillars but are not. They are covered in slime that

helps protect them from predators. When larvae mature,

they lose their slimy coverings. Around mid-June, larvae

will drop to the ground to pupate.

Management: Minor infestations of rose slug

sawfly can be controlled by using a forceful jet of water to dislodge the sawfly larvae or by

handpicking. Although this insect looks like a caterpillar, it is not, so Bacillus thuringiensis var.

kurstaki (Btk) will NOT control this pest.

Good website: http://hort.uwex.edu/articles/roseslug-sawfly

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Figure 4 Four-lined plant bug damage

Figure 5 Four-lined plant bug adult

Figure 6 Woolly beech aphid

Four-lined plant bug (minor)

Be looking for the four-lined plant bug (Poecilocapsus lineatus). Our

scouts found a nymph last week. This insect feeds on 250 species,

including many kinds of perennials, vegetables, and shrubs such as

bluebeard, forsythia, and sumac. Feeding injury is frequently

mistaken for leaf spots. Four-lined plant bugs have a piercing,

sucking mouthpart which they use to break plant cells and then flush

the feeding wound with digestive juices. Damage appears as dark leaf

spots which subsequently turn translucent (fig. 4). The damage is

more serious on herbaceous plants than on woody plants.

Sometimes by the time the damage is noticed, the insect isn’t there

anymore. Both nymphs and adults feed on leaves, creating the spots.

Nymphs are red and will develop dark wing pads as they

mature. The adult stage is 1/4” to 1/3” long and has four longitudinal

black lines on its yellow or green back (fig. 5), thus the name. It’s quite a shy insect that scurries

away when you try to find it. The insect overwinters as eggs laid

in slits cut into plant shoots. There is one generation per year.

Management: Some people try to hand-pick these

insects, but their timidity makes them difficult to catch.

Insecticidal soap should take care of larger infestations.

Good websites:

https://www.extension.umn.edu/garden/insects/find/fourlined-

plant-bugs/

Woolly aphids (minor)

The aphids have been showing up on plants, and now

their fuzzy cousins, the woolly aphids are out and about.

We have had reports on wooly beech aphids and woolly

birch aphids. Both these insects look a lot like regular

aphids, except they dress themselves up with a little bit of

white fluff. Like regular aphids, they are sap feeders and

also produce honeydew.

The woolly beech aphid (Phyllaphis fagi) (fig. 6) feeds only

on beech trees (Fagus spp). The woolly birch aphid

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Figure 7 Woolly birch aphids

Figure 8 Spiny oak sawfly

(Hamamelistes spinosus), however, has two hosts, birch (Betula spp.) and witch-hazel

(Hamamelis spp.). The insect overwinters on the bark

of a birch tree. When spring comes, she will give birth

to live young on the undersides of new leaves. The

feeding of the woolly birch aphid causes the leaf to take

on a corrugated look at first (this is the stage we

observed this week). Later, the feeding will lead to

curling of the leaves, with most of the insects tucked

into the lower side of the leaf (fig. 7) and protected by

the curling of the leaf.

In late June, the aphids will go to their other host,

witch-hazel. They will lay eggs on the twigs, and these eggs will overwinter on the witch-hazel.

The eggs will hatch, and the feeding caused by this generation of aphids will lead to the

formation of a spiny gall on the stem. The female produces a number of aphids in the gall, and

then she leaves the gall to fly to the birch.

Management: Both of these woolly aphids are fairly minor pests. They can often be

washed off the plant with a strong stream of water from the garden hose. Insecticides would

not be needed, unless a very high population of insects develops.

Good websites: http://hyg.ipm.illinois.edu/pastpest/200510e.html

http://hyg.ipm.illinois.edu/pastpest/200510f.html

More sawflies (minor to potentially serious) In the May 19 issue, we did a feature article about sawfly larvae. More species of these little

guys have popped up on a variety of plants, some doing a

little damage and some doing a little more. The spiny oak

sawfly larva was found feeding on bur oak (Quercus

macrocarpa). This is an easy one to spot due to the spiny

black hairs on his body (fig. 8). We have also had a report

of a sawfly larvae feeding on the leaves of creeping Jenny

(Lysimachia nummularia). This is most likely Monostegia

abdominalis, which was introduced from Europe. Looks

like it might be a big year for sawflies. Look at the May

19th article for more information on sawflies. Remember

that even though they look like caterpillars, they are not caterpillars. This means that Bacillus

thuringiensis var. kurstaki (Btk) won’t kill them.

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Figure 9 Apple scab

Carpenter bees (minor)

Carpenter bees have been seen in various areas around the Arboretum. Carpenter bees bore

into wood trim, outdoor wooden furniture, porch ceilings, dead tree limbs, and any weathered

wood. They excavate tunnels and can cause damage. They look like bumble bees, but are larger

and have a shiny black abdomen. The males cannot sting. Females will only sting if they are

agitated. They do not nest in living wood. Carpenter bees have strong jaws and chew 1/2 inch

round entrance holes on the underside of wood. They then chew horizontal tunnels up to

seven inches long. The bees are not actually eating the wood. They only create tunnels for

nesting sites. We don’t have any good pictures of this insect, so visit the websites listed below

to see what carpenter bees look like.

Management: Insecticides can be applied to the tunnel entrances on cool evenings

when bees are less active. Do not plug the tunnel entrance. All bees are pollinators, so don’t

kill them unless necessary.

Good web sites: http://www.ces.ncsu.edu/depts/ent/notes/Urban/carpenterbees.htm

http://ento.psu.edu/extension/factsheets/carpenter-bees

Pest Updates: Diseases

Apple scab (potentially serious)

Apple scab is showing up already and is progressing rapidly due to the wet conditions we have

had this spring. We are already seeing

development of the leaf spots. Early lesions

look like velvety, olive-green leaf spots and

will continue to develop into larger, irregular

dark spots Often lesions develop along the

mid-veins of the leaves. Infected leaves

eventually turn yellow (fig. 9) and drop

prematurely on susceptible hosts. This

defoliation can stress and weaken the tree,

especially if it happens year after year. The

fungus which causes scab (Venturia

inaequalis) overwinters on fallen leaves and on lesions on twigs. Sunken spots may appear

later on fruits, and susceptible crabapples can be completely defoliated in severe disease years.

Scab severity is a product of a specific temperature range, duration of moisture on leaves, and

host susceptibility. Scab severity is worse in wet springs, so we can expect to see quite a bit of

this on susceptible cultivars.

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Figure 10 New leaves blighted by sycamore anthracnose

Figure 11 Witches broom

Management: The best way to avoid apple scab is to plant resistant varieties.

“Resistant” just means that, in the typical year, a resistant plant won’t suffer as much from the

disease as a susceptible plant. However, it may exhibit symptoms in “bad” scab years. When

shopping for new crabapples, ask your local nursery which scab-resistant varieties they stock.

Caring for your trees, such as watering during summer droughts, may moderate effects of

defoliation and reduced photosynthesis in affected trees. As the fungus overwinters on fallen

leaves and blighted twigs, collecting and destroying them may help reduce the source of

inoculum next year. Spraying for apple scab needs to begin when leaves begin to emerge and

should continue (at labeled intervals) until two weeks beyond petal fall.

Good websites: http://www.mortonarb.org/trees-plants/tree-and-plant-advice/help-diseases/apple-scab

Sycamore anthracnose (potentially serious)

Earlier we reported on anthracnose on shade trees. We are now seeing anthracnose on

sycamore. The disease may be noticeable now as these large trees leaf out poorly (fig. 10).

Sycamore anthracnose is caused by the fungus

Apiognomonia veneta, and is more serious than the

anthracnose we see on other shade trees. Sycamore

anthracnose is common when we have cool, wet weather

during leaf development. Considerable defoliation may

occur in late spring, but trees normally bounce back and

produce a second set of leaves in early July that remain

disease-free. Leaves that are infected in early spring

often turn brown and shrivel while still small and may be mistaken for frost damage. Leaves

that are infected in late spring may show brown foliar lesions that extend along the veins, often

in V-shaped patterns. The leaves turn brown and may drop prematurely.

There are two other stages of this anthracnose: shoot and

leaf blight and canker formation. Shoot and leaf blight

results when the pathogen enters succulent shoots. It

causes the rapid death of expanding shoots and leaves. The

pathogen overwinters in twigs and is active whenever

temperatures are high enough in the fall, winter, and

spring. During winter, cankers form on infected shoots and

kill the buds. Repeated infection results in deformed shoots

and witches brooms (dense clusters of twigs). Although this

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Figure 12 Powdery mildew on ninebark

disease can weaken trees and increase their susceptibility to attack by other pathogens and

pests, it is not lethal.

Management: Dead twigs should be pruned as they develop throughout the growing

season. Rake and discard fallen leaves to reduce the source of inoculum. It is impractical to

spray fungicides on large trees, but for smaller, specimen trees, the disease can be controlled

with fungicides applied as leaves are opening. Systemic fungicide injections can also be used. If

you want to plant a Platanus species and don’t want to worry about sycamore anthracnose, you

can plant a hybrid planetree, that is resistant to the disease. Two common cultivars can be

seen on the Chicagoland Grows website (http://www.chicagolandgrows.org/index.php)

Good website: http://www.mortonarb.org/trees-plants/tree-and-plant-advice/help-

diseases/anthracnose-shade-trees

Powdery mildew on ninebark (minor to potentially serious)

We have not seen a lot of powdery mildew yet this season, but it is showing up on the leaves of

ninebark (Physocarpus opulifolius). The straight species of ninebark is relatively resistant to

powdery mildew, but some of the cultivars can be very susceptible and can sustain quite a bit

of damage. University of Connecticut has done some research on this. Go to

http://www.academia.edu/14492054/Susceptibility_of_eastern_ninebark_Physocarpus_opulif

olius_L._Maxim._cultivars_to_powdery_mildew to see their findings. Hundreds of plant

species are susceptible to powdery mildew, but the disease is caused by many different species

of fungi which are host specific. This means that the powdery mildew on coralberry will not

infect lilacs and so forth.

Powdery mildew appears as a superficial white to

gray coating over leaf surfaces, stems, flowers, or

fruits of affected plants. Initially, circular powdery

white spots appear. These spots coalesce producing a

continuous patch of “mildew.” On ninebark, the tips

of branches often develop a thick coating of white

powder (fig. 12), while other parts of the same plant

may show very few symptoms. Later in the season,

fungal fruiting bodies that look like black pepper

under a hand lens will appear. Warm days and cool

nights favor this fungal disease, and we have been

seeing this type of weather this year. The fungi that

cause powdery mildew are deterred by water since spores will not germinate in on leaves.

However, the fungus still needs high humidity to infect the plant. Leaf curling and twisting

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Figure 13 Leaf blight caused by brown rot

result, and in severe infestations you may see premature defoliation and deformed flower

buds. Although unsightly, powdery mildew is usually not fatal in the landscape.

Management: Infected plant parts should be removed as soon as symptoms appear.

Dispose of fallen leaves and do not handle plants when foliage is wet. Water plants during

periods of drought to keep them healthy. High humidity can increase disease severity so avoid

overhead watering in late afternoon or evening. Put plants in locations where there is good soil

drainage and sufficient sunlight. Provide proper plant spacing for good air circulation. Powdery

mildew on some plants can result in significant damage, and fungicides may be needed. To

obtain optimum results, spray programs should begin as soon as mildew is detected. In the

future, plant mildew-resistant cultivars and species.

Good website:

http://www.mortonarb.org/trees-plants/tree-and-plant-advice/help-diseases/powdery-

mildews

Brown rot of stone fruit (serious)

The Plant Clinic at The Morton Arboretum has received a couple reports of brown rot on

cherries. Brown rot is caused by the fungus Monilinia

fructicola which can infect peaches, plums, cherries,

apricots, and other Prunus species. The disease is

sometimes seen as blossom blight – the browning and

sudden collapse of blossoms. The infection can spread

into shoots and twigs during the next several weeks

resulting in shoot and twig blight (fig. 13). This is the

stage we observed. Cankers, which may be

accompanied by a gummy ooze at their margins, form

on twigs often causing twig dieback. Infections of fruit

start as brown spots that rapidly infect the entire fruit, completely covering it with spores and

giving it a fuzzy look. Infected fruits decay and shrivel; some will stay attached to the tree

throughout winter while others will fall to the ground. These ‘mummies’ provide inoculum for

the following spring.

Management: Sanitation is crucial to control of brown rot. Prune out active infections

immediately during dry weather. Don't forget to disinfect pruning tools. Rake and clean up

debris under the tree during the summer to remove fallen leaves and fruit. Prune to promote

good air circulation through the tree canopy. Wild or neglected stone fruit trees (e.g., wild plum

and cherry) in the area are likely to have the disease and be sources of inoculum that should be

removed. Later in the year remove rotted fruit ‘mummies’ that are persistent, and prune out

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Figure 14 Old black knot (left) and newer infection (right)

cankers and infected twigs. If damage is severe, fungicides need to be applied when blossoms

first open in early spring.

Good websites: http://ohioline.osu.edu/hyg-fact/3000/pdf/HYG_3009_08.pdf

http://www.ag.uiuc.edu/~vista/abstracts/a804.html

Black knot (potentially serious)

Black knot (Dibotryon morbosum) is a serious and widespread problem of trees in the genus

Prunus, especially plum and cherry trees. The

Plant Clinic at The Morton Arboretum receives

questions on this problem year round since it is so

prevalent and so easy to spot. Now is the time to

look for new abnormal swellings on branches of

cherry, peach, plum and related trees. The fungus

overwinters in the hard, brittle, rough, black

“knots” on twigs and branches of infected trees

such as wild black cherries in the woods (fig. 14).

These knots may be small or may be several inches long and wrap around the branch. In some

instances the main trunk of the tree can become infected.

In the spring, the fungus produces spores within tiny fruiting bodies on the surface of these

knots. The spores are ejected into the air after rainy periods and infect succulent green twigs of

the current season’s growth. The newly infected twigs and branches swell. The extensive

overgrowth of bark and wood is a response to hormones and produces the smaller swellings

that we are now seeing. Frequently these swelling are not noticed the first year. The swellings

become dormant in winter. But the following spring, velvety, green fungal growth will appear

on the swelling. The swellings darken and elongate during summer and, by fall, turn hard,

brittle, rough and black. The black knots enlarge and can girdle the twig or branch, eventually

killing it.

Management: This is a difficult disease to manage. Prune and discard all infected

wood during late winter or early spring before growth starts and when new swellings appear.

Pruning cuts should be made at least six inches below any swellings or knots. In advanced cases

with many knots, pruning out branches may not be feasible as it may destroy the shape of the

tree.

Good web site: http://www.mortonarb.org/trees-plants/plant-clinic/help-diseases/black-knot-ornamental-cherry-and-plum

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Figure 15 Tobacco rattle virus on epimedium

Figure 16 Poison hemlock has a spotted stem

Viruses (some minor, some potentially serious)

We are starting to see some plants exhibiting viral symptoms already this year. We have seen a

virus on geranium and tobacco rattle virus on

barrenwort (Epimedium spp.) (fig. 15). We have

also received a report of mosaic virus on Katsura

tree (Cercidiphyllum japonicum). Viruses seldom kill

their hosts, but the plant will always be infected and

many viruses can be spread by insects that feed on a

diseased plant and then move to a healthy plant to

feed. Virus symptoms can vary by plant and by virus.

Common symptoms include mottling, mosaic

patterns and excessive growth of plant parts.

Management: There is no chemical

management of viruses. Once the plant is infected, it cannot be ‘cured’. There are two options

for dealing with viruses. First, you can keep the plant and live with the fact that it has the virus.

For some plants this is an acceptable option, especially if it does no serious damage to the plant

or there are no other plants of the same species nearby to become infected. The second option

is to destroy the plant. This is a good idea with small plants like roses, hostas or raspberries

where there are other plants of the same species nearby that might become infected.

Weeds Poison hemlock (dangerous)

The Plant Clinic has been receiving reports of poison hemlock (Conium maculatum) popping up

in home gardens. This weed has been fairly prominent for

the last few years, not only in home gardens, but popping up

along the side of the road in many areas. Poison hemlock is a

member of the carrot family (which contains both edible and

toxic plants, so beware!!). Most members of this family have

the same type of umbrella-shaped flower cluster know as an

umbel. Because the flower cluster of Queen Anne's lace and

the flower cluster of poison hemlock look similar, plants may

be incorrectly identified. This can lead to contact with a

dangerous plant.

Poison hemlock is a large, non-native plant (often 6 feet or

more). The smooth stem is stout, has a ridged appearance

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Figure 17 The ferny leaves of poison hemlock

Figure 18 Creeping bellflower

and is marked with purple spots (fig. 16). The stem is

hollow. Leaves are large and very ferny in appearance

(fig. 17). Poison hemlock is a biennial plant, which means

it will form foliage in the first year and flower and set

seed in the second year. Plants in their second year are

starting to flower and have the typical white flower

cluster (umbel) of the carrot family. Queen Anne's lace

has one red floret in the center of its flower cluster,

poison hemlock does not.

All parts of the plant are toxic and may lead to death if

ingested. The plant's oil may be absorbed through the skin, so long sleeves and gloves will be

needed when handling the plant.

Management: Plants can be cut down or dug out. This should be done before the plants

go to seed and is most easily done when plants are small. Cover your skin during this process.

Do NOT burn the plants. In spring, small, actively growing plants may be treated with an

herbicide containing glyphosate.

Good websites: http://hyg.ipm.illinois.edu/article.php?id=380

http://www.btny.purdue.edu/weedscience/2003/articles/PHemlock03.pdf

Creeping bellflower (aggressive)

For the last few years, we have been receiving reports of an annoying weed making itself

known in flower gardens and lawns. There are actually

two plants that are nearly identical, ladybells

(Adenophora spp.) and creeping bellflower

(Campunula rapunculoides). The two plants differ only

by a small structure within the flower. Ladybells and

creeping bellflower are closely related, but on doing a

little research, it seems that the creeping bellflower

may be the ‘bad seed’ of this family. It is the one that

seems to be overly aggressive. Unfortunately, because

the plants are so identical, if a friend shared some

ladybells with you from her garden, you may actually

have creeping bellflower.

Young plants have leaves that are heart-shaped to lance-shaped (fig. 18). This innocent looking

plant has fleshy roots growing horizontally under the soil. These fleshy roots help to spread the

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Figure 19 Patch of creeping bellflower

plant and before you know it you have a healthy patch of them in your flower bed (fig. 19). If

the plants are not removed, a flowering stalk with

purple, nodding, bell shaped flowers will form.

Management: Plants can be removed

manually through digging, but any roots left will

continue to produce new plants. As new plants

develop and are actively growing, spray them with a

weed killer containing glyphosate. Glyphosate will be

absorbed by the leaves and taken down to kill out the

roots. Do not get the glyphosate on desirable plants

as it will kill them as well.

Bartlett Tree Experts, Presenting Sponsor of the Plant Clinic.

The Plant Health Care Report is prepared by Sharon Yiesla, M.S., Plant Knowledge Specialist and edited

by Fredric Miller, Ph.D., Research Entomologist at The Morton Arboretum and Professor at Joliet Junior

College; Doris Taylor, Plant Clinic Manager, and Carol Belshaw, Arboretum Volunteer. Frank Balestri

M.S., Plant Health Care Technician/Research Assistant is responsible for coordinating the scouts. The

information presented is believed to be accurate, but the authors provide no guarantee and will not be

held liable for consequences of actions taken based on the information.

Thank you...I would like to thank the volunteers who will be scouting for us this season. They find most

of the insects and diseases reported here. The Scouting Volunteers include: Maggie Burnitz, LeeAnn

Cosper, Ingrid Giles, Emily Hansen, Ann Klingele, Pat Miller, Loraine Miranda, Julie Moore, Mary Noe and

Wendy Vichick . Your hard work is appreciated. Thanks also to Donna Danielson who shares her

scouting findings.

Literature/website recommendations:

Indicator plants are chosen because of work done by Donald A. Orton, which is published in the book

Coincide, The Orton System of Pest and Disease Management. This book may be purchased through the

publisher at: http://www.laborofloveconservatory.com/

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Additional information on growing degree days can be found at:

http://www.ipm.msu.edu/agriculture/christmas_trees/gdd_of_landscape_insects

http://extension.unh.edu/resources/files/Resource000986_Rep2328.pdf

The Commercial Landscape & Turfgrass Pest Management Handbook (CPM), for commercial applicators,

and Pest Management for the Home Landscape (HYG) for homeowners from the University of Illinois,

are available by calling (800-345-6087).

This report is available as a PDF at The Morton Arboretum website at

http://www.mortonarb.org/visit-explore/news-events/arboretum-news?tid=259

For pest and disease questions, please contact the Plant Clinic at (630) 719-2424 between 10:00 and

4:00 Mondays through Saturdays or email plantclinic@mortonarb.org . Inquiries or comments about the

PHCR should be directed to Sharon Yiesla at syiesla@mortonarb.org .

Copyright © 2017 The Morton Arboretum

Not printed on recycled paper, or any paper for that matter.