Problems in the Garden
This week Buggy Joe Boggs (OSU Extension) is reporting antlions (one of Joe’s favorite bugs) now creating their cone shaped pits to capture ants in, calls concerning lack of bean development in many bean pods (thanks to high temperatures), second generation of fall webworms, second generations of mimosa webworms, a few calls about ‘potter wasp’ nests (actually looks like a miniature clay pot – really cool!), walnut caterpillars feeding in large groups, dogwood sawflies feeding a, yes, dogwood leaves, leaf blotch really doing a number on ‘Aesculus ‘ leaves (Buckeye included), and if you have bagworms, the feeding has started to slow, most severe damages are done (although they can keep going for a few more weeks), and sprays now may kill a few, but actually triggers them to stop feeding totally – even if you only kill a few, you may stop them from further feeding (use Spinosad).
-Catch The Buggy Joe Boggs Report Saturdays at 8:42am on 55KRC The Talk Station. You’ll also find his blog at www.ronwilsononline.com.
Extra, Extra, Read All About It!
“Social Bees & Wasps Frighten Folks” – Dr. Dave Shetlar, The Bug Doc
I am always a bit amused when I hear of the encounters that homeowners have with social wasps! Just last week, a person called in to report that he had “suddenly” discovered a football-sized bald-faced hornet’s nest just outside his front door. This nest has obviously been building in size since May, yet the homeowner hadn’t noticed it! This just reinforces entomologist’s contentions that most of the social wasps are quite benign, and in fact, beneficial (mainly insect predators). HOWEVER, now is the time that these social wasps, especially yellowjacket species, bald-faced hornets, and our European paper wasp, become more aggressive in seeking sugary foods. This is the time that people-wasp interactions are most likely to occur. In short, up to now these wasps have been feeding on other insects, primarily caterpillars, sawflies and flies. The wasp workers capture these insects, chew them up and take the “bug burger” back to the nest to feed the helpless maggots (their larvae) that are growing within the individual cells located with each nest. Until now, the queen wasp has been laying eggs that produce only sterile female workers. However, now the queen begins to lay eggs that will develop into new queens and drones. These new queens will have fully developed reproductive organs, but they won’t produce eggs until next spring. New queens and drones don’t forage for food like the workers do, but usually hang around the nest begging the workers for food. In this case, these reproductives prefer high carbohydrate foods rather than the high protein food needed by the larvae.
The workers pick up on the begging and begin to switch their foraging behavior to find foods with high sugar and yeast content. Of course, this means that they become real nuisances around parks, outdoor eating establishments and other places where people like to have sugary drinks, fruits and even beer. And these wasps have a memory! They remember where they were successful in finding high sugar foods and they will return again and again, often after recruiting fellow workers. This is why outdoor feeding establishments and amusement parks have to be diligent at maintaining self-closing trash cans regularly picking up or washing down food and drink spills and practicing similar sanitary procedures.
The German yellowjacket, eastern yellowjacket, yellow hornet and bald-faced hornet are the most common species of social nuisance wasps found in Ohio urban and suburban areas. Most entomologists claim that these wasps are generally “non-aggressive” except if you get near their nests. This is usually misunderstood by the average person. What we’re talking about is their tendency to sting, not their persistent behavior to pursue food! These wasps can be very “aggressive” in pursuit of their food, but unless you physically restrain them (trap them under clothing, step on them, or get them caught in a soda can), or strike them while flaying your arms in an attempt to shoo them away, they won’t sting.
In fact, I’ve forced myself to be very unafraid of wasps buzzing around me or even landing on my arm or clothing. In most cases, they are simply inspecting me to determine if I’m food or not! On the other hand, if one strikes me or persists in buzzing loudly in front of me, I must assume that I may be close to a nest and this worker is giving me a warning to move away. Honey bees, bumble bees and many wasps do give “warnings” if you are willing to listen! Stinging is really the last resort and the behavior can be very risky for the bee or wasp. Honey bees actually die after stinging because their barbed stinger gets stuck and pulls off the tip of the abdomen when the bee departs.
My general recommendation about social bees and wasps is to try and avoid getting near their nests. They’ll be gone after the first hard frost. However, if you happen to find a nest that has been built under the mulch in a flower bed, a hole in the lawn, or other place where you may regularly need to perform maintenance, control may be necessary. There are all kinds of wasp and hornet aerosol sprays on the market, but these are generally inadequate for control of bees and wasps that nest in the ground or in wall voids. Only the umbrella wasps, Polistes, can be easily hit with these sprays. If you can locate, during the day, where the yellowjackets or bumble bees are entering their nests, try to determine where the wasps or bees land before crawling into the nest chamber. Make a mental note of this. Your strategy will be to dust this area with an insecticide, AT NIGHT, when the bees and wasps are unlikely to fly or be disturbed. My favorite insecticide to use is Sevin 5% or 10% garden dust, but you can find other garden dusts with pyrethroids. Thoroughly dust the landing spot with the dust so that the next day most of the bees or wasps will walk through the material. Once they walk through the insecticide dust, the insects will carry the material into the nest. There, the bees and wasps will groom themselves and each other, distributing the insecticide throughout the colony. I’ve been pretty successful at knocking out a colony with one application, but sometimes a rain or irrigation can wash away the insecticide dust, so another application may be necessary in a few days. –Dr. Dave Shetlar, The Bug Doc