What's Bugging You?
Holy horticulture, Mr. Stone, what a beautiful spring! Warm days, cool nights, rain enough for everyone and an expected high of 78 degrees with possible rain for Memorial Day weekend. As a kid, Memorial Day was my favorite holiday. The small northern Illinois town I called home, boasted the greatest parade anywhere. It was everything I could do each Memorial Day morning to choke down Tony’s Frosted Flakes, hit the street, gather all my friends and secure the best seat our Village Green had to offer. It included firemen, (persons), policemen, (persons), fire trucks, police cars, Lions Club, Rotary, clowns, the Mayor, people in wheel chairs and walkers as well as enough boy and girl scouts to populate the entire city of Chicago. Where did all those kids come from? Incredibly, my dad has 16mm film footage of every single person in each parade. Some families have closets full of old clothes and kids’ toys. Not the Deahl family, we have rooms stuffed with film canisters documenting the daily development of four children and their cousins from 1948-1970. My dad made sure my face was on more film than Bruce Willis or Mel Gibson ever thought possible. It couldn’t have been more fun. That is what life’s all about, isn’t it?

While walking with my friend Vicki, in her garden over on Edgartown Street yesterday, we noticed some bugs that were gathering momentum for their usual summer assault. Vicki suggested discussing some of these critters with all of you. Great idea Vicki, thanks, and what a great job of naturalizing your backyard, it’s beautiful and healthy!

Bug rule #1: Due to their insistent adaptability, it is virtually impossible to eradicate any species of bug, mite or insect. Instead, we may only bring their populations to a tolerable level, temporarily.

Bug rule #2: By putting the right plant in the right place, which usually means an indigenous or native species, most bugs, mites or insects cannot inhabit that plant due its own innate characteristics and surrounding environment. Make sense?

Example. What happens when you put azaleas in full sun? Enter our first critter, the transparent Lace bug. These are the wonderful little creatures that while sucking the chlorophyll from the leaves insist on depositing their fecal matter on the underside of each leaf. As in most cases you will notice the manifestation of this insect, not the Lace bug itself. They will give azalea leaves a straw colored, bleached look that cuts down on the photosynthetic process affecting the shrub’s health. Azaleas do not enjoy full sun but instead, mottled shade. By placing them in the correct shady situation Lace bug populations will be smaller. Lace bugs can be treated with oil, soap or insecticides throughout the summer. Lace bugs and their droppings stay on the underside of the leaves, making treatment and application of products difficult. 

Another word on Hemlock woolly adelgid, (we discussed this villain last year). This fellow is becoming well known. Most clients I meet can identify this ball of fluff. Formerly known as woolly aphid, it now is a beast in a class all its own. Knowing what you are looking at is important with this pest. The white fluffy casing is obvious most of the year but only eggs are present from March through June so treatment at this time will be fruitless. Immature crawlers will be found from June until October so this is the time to treat. Again oils, soaps or insecticides will work along with dormant oil applications to hemlocks from November through the end of February. Systemic insecticides can be applied to the tree’s root system for uptake into the leaves but should be done professionally. These guys have two generations per year so get with your arborist to determine timing and efficiency. Treatment of adelgids is important. They are an introduced pest and have wiped out entire stands of native hemlock. Stressed trees are more susceptible than others and proper treatment and timing will be effective. Remember even after you have killed the adelgid the white fluff will remain. Simply rub some between your fingers and if it is dry, celebrate!

We will be seeing Japanese beetles soon on roses, lindens and plums. Not much can be done due to the beetle’s long adult life span and their feeding techniques. Do pheromone bags and traps attract the beetle? Probably. Will they attract the beetle into your yard? Probably. It’s a tough call and is a pest we will we need to put up with, unless we plant things the beetle doesn’t like. There you go! I knew you’d come up with the right answer!

I’ve noticed more gypsy moths this year but no serious defoliation at this point. It will be important to monitor egg cases on the bottom of oak, beech and hickory limbs but will not be limited to only those trees. Gypsy moths seek out places to hide their tan, velvet-like egg cases, so trees covered with ivy fall prey to the adult moths when they are ready to lay eggs. Fall webworms are on the way and will bother cherry and other fruit trees. Just as with Eastern tent caterpillar, remove their tents with a stick and dispose of properly. In contrast with Eastern tent caterpillar, webworms build their homes around the ends of branches and never leave the tent. Eastern tent caterpillars build in tree crotches and migrate throughout the entire tree. Mechanical removal of nests is the best plan.

There is one more critter we should cover, one that’s much too small for the naked eye to spot, any guesses? It’s not an insect. MITES! Arachnids, spiders, eight-legged crawlers. Some are good, some not so good. Remember our insects have six legs and most mites, eight. These guys are microscopic and come well equipped with sucking mouthparts that also take the chlorophyll from the leaf. They leave the leaf looking pale yellow or “etched” with yellow markings. Most plants are affected by mites, especially those under stress and once again, those living in the wrong spot. Boxwood, holly, azaleas, junipers, arborvitae and many others are affected. Here’s the tough part about mites. They can have up to EIGHT generations each year. Control, at times, is vital. Oil and soap can work but miticides that kill adults and eggs are most effective. Before treating anything consult with your arborist. Beneficial insects can keep low pest populations at bay. By using the wrong chemicals we can upset the natural balance between predator and prey. This is another reason why the correct plant in the correct location is so vital.

That’s a quick overview, so please forgive my brevity on such a detailed subject. Hopefully it may give you information to aid in recognizing concerns before they become serious.

By the way, my folks just called from Chicago. They are headed for the parade. I’m afraid I’ll miss one more, not really. I’m sure the cameras are rolling, with dad armed to the teeth with F-stops and shudder speed ready for the most unsuspecting of characters. Thanks to everyone for your support. Thanks from one Vet to another! Happy Memorial Day!

Copyright 2005 by Peter Deahl. All rights reserved.
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