decorah envirothon - good bugs, bad bugs

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Good Bugs, Bad Bugs

Good Bugs, Bad Bugs

Todays presentation is about some of the bugs we like and some that we do not. Does anyone know what bug is in this photo? The honeybee!1

Honeybees are arguably the most beneficial bugs in the world.


We know they pollinate most of our beautiful wild and garden flowers.

Other insects play a huge role in pollinating both wildflowers and garden flowers. The good thing about honeybees is that they can be transported to huge fields of almonds in California where there are not enough natural pollinators to do the job.3

Honeybees are also the main pollinator for many crops we grow for food.

They say about 1/3 of humanitys crops rely on insect pollinators. In NE Iowa the most important crops would probably be apples and alfalfa. Most vegetable and sweet fruits need insect pollinators; grain or cereal crops do not. 4

This apple orchard blooming in April needs to be visited by bees before any fruit can form.

Red ripe apples in autumn, thanks to the work of busy honeybees.


Honeybees get a reward, in the form of nectar, for that work.

Honeybees turn that nectar into honey, which we can siphon off a sample from their hives, for a real sweet treat.

The cicada killer is another bee, albeit a big one, that could be considered beneficial.

Cicada killers key in on catching cicadas. Surprisingly, they dont eat cicadas but their larvae do. Adults drink flower nectar

A cicada, also known as the harvestfly. Cicadas are famous for making a deafening din around the neighborhood in summer.

Some cicada species spend 17 years underground, slowly growing into that creepy-looking critter, before crawling out.

Baby cicadas climb up a tree trunk before splitting their skin and popping out the noisy flying adult form

Lady beetles are often called ladybirds or ladybugs, but they are indeed beetles.

Native lady beetles are never a nuisance and hibernate under decayed tree bark out in the woods. They dont bite or stink.

Asian lady beetle adults can be big problems for people. They seek winter shelter in our houses en masse & smell awful.

Another good one is the Halloween ladybug, because that is the time of year that it tends to show up in peoples homes. Originally from Northeastern Asia, it was brought to the U.S. and used to control aphid populations in greenhouses throughout the 20th century. A wild population got established in the early 1990s and by 2000 it had become common in the Upper Midwest.


All ladybird beetle larvae are beneficial. They eat aphids and scale insects and other bugs that cause gardeners headaches.A

All ladybird beetle larvae are beneficial. They eat aphids and scale insects and other bugs that cause gardeners headaches.A

The Asian lady beetles actually make a huge difference for farmers by eating up thousands of soybean aphids.18

Adult lady beetles are also predators and feed on mealy bugs and spider mites. They can live for three years!

These characteristic make lady bugs a popular choice for greenhouses and other small-scale agricultural producers to purchase as beneficial insects to keep pests like spider mites under control.19


Green lacewings are another good bug to have around the house.

Green lacewings are named for their delicate lacy-looking wings. They live out in the fields and around our gardens and adults feed on flower nectar. Theyre most active in the evening.

Green lacewing larvae look like little alligators and aggressively attack 70 other bugs, mostly bad things like aphids & thrips.

Thrips are also called corn lice and suck the juices from commercial crops like corn & soybeans as well as garden crops.

This plain-looking bug looks pretty dull during the day but really shines at night, hence the common name firefly

Fireflies or lightning bugs are actually beetles. The strange light source is located under those wings on their abdomen.

There are a few ways to tell the difference between a bug and a beetle. Beetles will always have two plates called elytra that cover up their wings when they arent flying. True bugs have more membranous that stay exposed.

Beetles are often omnivorous, and they have mouthparts made for chewing. True bugs use straw-like mouthparts to feed on juices; usually they go for plant sap or nectar, but some will consume animals. 25

Fireflies use that cool green light to attract mates; each sex sending out communication signals to identify their species.

Firefly larvae are specialized predators that focus on snails & slugs in the swampy areas they like to live.

Firefly larvae suck the life juices right out of captured slugs. They glow in the dark too, all the time, & are called glowworms.

Heres a glowworm going right inside the shell to get to the snail hidden inside.

The best-known good bug is probably the praying mantis.

Praying mantis look like science-fiction monsters.They suck the life blood right out of luckless flies.

Harvestmen, or daddy longlegs, look like spiders but notice how their whole body is fused into a single oval form.

In addition, daddy longlegs dont spin webs and they dont have venom so they cant hurt you. Note the really long legs.

Harvestmen eat small slugs and bugs, like this tiny froghopper.

Harvestmen eat small slugs and bugs, like this tiny froghopper.

They are called froghoppers because of their excellent jumping abilitiesup to 2.5 feet vertically. They have relatives called leafhoppers and tree hoppers.34

Froghopper nymphs are known as spittlebugs, famous for making frothy white hideouts that look like spit.

A spittlebug basking in a tub of bubbles.

Garden spiders arent insects but might be considered good bugs.

Garden spiders set out nets to capture critters like grasshoppers that are quickly consumed.Garden spiders are harmless to people even though they look dangerous.As the saying goes, live and let live.

Garden spiders often surprise me when I am walking through weedy, neglected corners of my familys garden.38

This little crater in the sand is made by an insect called the ant lion. Careless ants crawl in and then cant crawl back out.

When a trapped ant reaches the pits bottom, that immature ant lion rears its head out and eats the ant.

Immature ant larvae are awfully ugly little bugs.

Adult ant lions look a lot different than those grotesque larvae.

Adult ant lions have long webby-looking wings and live around sand prairies here in Iowa.

Robber flies are always on the lookout for another victim.

Robber flies hunt down and attack other airborne insects, including pesky flies or scary bees.

Goldenrod soldier beetles search for aphids to eat, especially aphids that are infesting goldenrod plants.

Black ground beetles may look bad but they eat slugs.


American carrion beetles are natures garbage collectors, consuming dead stuff.

These American carrion beetles are tricked by a smelly stinkhorn mushroom.

The beetles will help transport the mushrooms spores to new territory. Many plants use the same trickstinky flowers encourage flies and beetles into performing pollination services. 49

Dung beetles clean up critter poop

Burying beetles serve as natures undertakers, digging underneath small dead animals like mice so they fall into a hole, and then covering up that critter so they can feed in safety and comfort.

These brightly-colored burying beetles are checking out a dead squirrel body.


And then weve got our bad bugs like aphids

Aphids are really tiny little bad bugs.

Aphids suck the nutritional juice straight out of plants. Their mouth is designed like a straw

Aphids are a real problem when they become abundant, cutting down on plant productivity if not killing them.

This beautiful little moth, the squash vine borer, might not be welcome in the garden

Squash vine borer moth larvae burrow right into the squash vine

Affected squash plants soon wilt and die.

There are a couple of ways to help avoid damage from the squash vine borer. In NE Iowa we can cover up the squash plants while they are small. That helps the plant get started and produce some fruit before the borer can kill the plants. Take of the row cover when the first flowers start to appear. Crop rotation, secondary plantings, simple traps, insecticides, and physical removal of the larva are other steps that gardeners can take to deal with this pest.59

The Colorado potato beetle is another common garden pest, also called the ten-striped spearman.

They became a pest in Colorado during the 1800s when the beetle decided to start eating potatoes rather than its normal host, the buffalo bur plant. Now they prefer potatoes, but they will also prey upon eggplant, peppers, tomatoes, and other solanums.60

Colorado potato beetles & their larvae eat potato plants.

Colorado potato beetles can be very prolific.

There are usually 2 generations per year in the northern Midwest.62

Colorado potato beetle eggs are laid beneath potato leaves and are yellow.


Colorado potato beetle larvae get fat fast feeding on potato leaves.

The larva are awfully gross, glistening things. They are one of the few bad bugs that I dont enjoy squishing. The older larva are responsible for most of the damage.64

Potato plants look like skeletons after Colorado potato beetles are done feeding.

Management is difficult. Insecticides and crop rotation are ineffective. Using early maturing varieties, limiting the number of alternate hosts (ground cherry and nightshade), and hand plucking the beetles from the plants are the three best techniques for the home gardener.65

Japanese beetles are major defoliators of prized lawn plants.

The good news is that these beetles are not extremely common in NE Iowa. They may become so in the coming years. As with many infestations, the beetles are moving westward from the Northeastern United States.66

Japanese beetles digging into one of their favorite plants, the lovely pink rose.

Plant leaves are pretty well shot by Japanese beetles.

Insecticides and pheromone traps are used to control these beetles, but the versatility and hardiness of this insect makes it difficult to control at this time.68

The emerald ash borer is making inroads into Iowa, creating concern about the future of Iowas ash trees.

Arrived around 2002 near Detroit. At least a dozen counties in Iowa have had sightings, including Allamakee.69

Ash trees are a popular shade tree in the state.

Ash trees can provide some nice yellow color in the autumn. The Iowa DNR estimates that there are about 52 million ash trees in Iowas woodlands and about 3 million ash trees in our cities and towns. 70

Emerald ash borer larvae tunnel into ash tree trunks, feeding as the crawl around.

Emerald ash borer larvae leave these S-shaped feeding chambers behind after theyve strangled the ash tree.

The cambium layer of tissue just inside the bark is essential for nutrient and water transport within the tree. If the larva feed and destroy around the circumference of the tree, they girdle the tree.72

Afflicted ash trees try to survive by sending out suckers.

See the tree on the left.73

The Asian long-horned beetle is another terrible tree killer.

Note those long striped horns which are actually antennae.


Asian longhorn beetles are inclined to attack and eliminate maple trees.

Maple trees are like ashvery common in our woodlands and very popular as street trees. Some communities could lose 1/3rd to of their street trees if ash and maples are killed.75


Maple tree damage by Asian longhorn beetles.

The worst part is that the Asian longhorn beetle doesnt just prey on maples. At least 10 other tree species are eaten including birch, willow, elm, and poplars.

The good news is that ALBs arent prevalent in the USA yet. There are infestations in Massachusetts and Ohio right now; infestations in Chicago and NYC seem to have been eradicated.76

The lowly-looking gypsy moth is yet another forest menace.

Introduced in the 1800s, because its caterpillars seemed to have potential for silk production.77

Gypsy moth caterpillars are colorful but killing consumers.

Gypsy moth caterpillars key on oak trees out in the woods.

A normal healthy bur oak leaf.

A bur oak leaf eaten by gypsy moth caterpillars

Not just oaks are under threat. Aspen, apple, basswood, birch, cottonwood, willow, and white pine are also infested. As of 2007 they were well established in Eastern Wisconsin, so its probably just a matter of time before they reach NE Iowa.81

Some people consider the tiny mosquito a real terror.

Mosquito larvae are aquatic, suspended just beneath the surface film where they grow bigger while grazing on algae.

When adult mosquitos metamorphose, theyre mighty hungry.

They start to graze on yummy warm-blooded mammals like us!84

Female mosquitos need a blood meal to make their eggs.

Perhaps the biggest problem with mosquitoes is there habit of transmitting diseases such as malaria, Dengue fever, and the Zika virus. The good news is that new genetic techniques are bolstering the more traditional approaches of spraying insecticides and draining standing waterways. 85

Deer flies are colorful but problematic pests

Deer flies live out in the woods where they watch for warm-blooded animals or people to come walking by.

Deer flies slyly land on exposed skin and stab right in.

Homemade deer fly stopper(duct tape)

Horse flies are usually a bit bigger than deer flies with clear or cloudy wings unlike the dark patches or stripes on the deer flies.89

Bald-faced hornets are normally harmless, feeding on flowers.

Bald-faced hornets chew leaves up to form a papery nest.

Bald-faced hornets hide their nests among the leaves in trees.

I had a lot of fun finding old hornet nests when I was a kid. I dont seem to find as many of them as I used to.92

These bald-faced hornets are in a bad mood. They attack and sting if you stand too close.

Bald-faced hornet nests are made of homemade paper and being fragile, fall apart in autumn when all but the queen die.

Bumblebees are usually good bugs, pollinating plants. Note the orange purple prairie clover pollen on these bumblebees legs.

There are many types of native bumblebees; the bad news is that some have experienced dramatic declines like the honeybee. Perhaps neoniconitoid insecticides and loss of nectaring flowers are to blame.95

Bumblebees become bad if you accidentally step on their nest, which is constructed underground

Maybe the worst wasp menace are the Yellow Jackets

Some species are native to the U.S. A couple have been introduced from Europe and are somewhat invasive.97

Yellow jackets are smaller and slimmer than most other bees. They can sting multiple times with a searing venom.

Yellow jackets live underground and aggressively defend a wide space all around their hidden nest.

Yellow jackets often show up at summer picnics to mooch off our plates, and can get rather testy when shooed away.

Despite their pesky characteristics, some yellow jackets do predate upon other insects when there isnt a group of picnickers to bother.100

This four-spotted sap beetle is more commonly called a picnic bug.

Picnic bugs show up to feast on fruits at fall picnics

Boxelder bugs are quite pretty out in the country.

By the way, heres what baby boxelder bugs look like in summer

Boxelder bugs are attracted to boxelder trees, becoming especially abundant in September.


Boxelder bug search for secure wintering sites in hollow boxelder trees.

House foundation cracks are equally attractive winter quarters.

The cluster fly is another concentrating pest. They live all alone out in the woods during summertime.

When the weather turns cold, cluster flies swarm to warmer wintering sites, waking up on sunny days.

Cluster flies are a bit difficult to distinguish from house flies unless you get a close look at them. They are usually a bit larger than the house fly; they fly more slowly; and their wings overlap almost completely when they are at rest. The best way to keep both bugs out of the house is by sealing up the cracks that allow them to get inside. A good old flyswatter can take care of the rest.109

Carpenter ants are destructive colonial characters. Theyre all black and big for an ant, up to a quarter-inch long.

Carpenter ants carve out their large multi-chambered community homes deep inside soft wet rotting wood.

Out in the woods, pileated woodpeckers keep the carpenter ants under control.


Around the house carpenter ants can undermine foundations

Termite damage looks a lot like carpenter ant work.

Termites also live in large colonies, but unlike ants they actually eat wood, chewing up the cellulose and leaving huge hollows.

The good news is that termites are rare to uncommon in Iowa. Sometimes it is a bit difficult to tell the difference between a termite and an ant. Ants will have dark bodies, bent antennae, a narrow waist, and smaller set of hind wings. In contrast, a termite will be light colored with a broad waist and wings of equal length. Ants can be seen in open areas in the evening whereas termites shy away from the light and are rarely seen.115

The German cockroach doesnt do any real damage in the house, but

They can be mighty creepy when they come out from behind the walls at night.

An even creepier critter that calls our house home is a centipede

Centipede means a hundred legs, and they dont look like they lie. Centipedes slide behind the woodwork during the day.

Centipedes actually always have an odd number of leg pairs. Different species have anywhere from 30 to 354 legs. Millipedes have 2 pairs of legs per body section; centipedes have just one pair. Centipedes are carnivores and millipedes are detrivores.119

Centipedes come out to play on our pillows at night.

Chiggers are not really bugs, but tiny mites that are closely related to spiders.

Chiggers, or scrub mites, like to live in dry sandy grasslands.

We dont have too many chiggers in this area because we dont have the right habitat. Farther south, chiggers can be a real problem.122


Baby chiggers crawl aboard as we pass by grass blades where they perch, and then they feed on our skin.

Chiggers irritate our skin and cause red welts to form. This itching agony can last for days.

The wood tick , aka. dog tick, climbs up on grass stems out in open fields, not in the woods, and waits to hitch a free ride.

Wood ticks are big enough to see when theyre crawling on your skin.Females take a blood meal to make their eggs.

A well-fed female wood tick looks absolutely awful.

Deer ticks are a lot more dangerous than wood ticks.

Deer ticks are tiny and difficult to see, not much bigger than a pinhead.

Deer ticks can carry a bacteria that causes Lyme disease, a debilitating condition characterized by fatigue and joint pain. One symptom is a bull's-eye rash where the tick bite took place.

Wearing long pants and walking on trails will help reduce problems with deer ticks and other bad bugs.