more...

>

Insects and Relatives

>

Bugs, Bugs, Bugs Newsletter

>

Bugs, Bugs, Bugs July 2008 Bugs, Bugs, Bugs July 2008 Although the month started off slowly, insect activity has gained momentum, and several insects are causing the public to have some serious questions. Here is what is of concern to date. Asian wooly aphid — The summer snowflakes -- as some have called them – are heavily infesting the hackberry trees again. This aphid is floating/flying through the air in many subdivisions and backyards as they are blown, shaken or fall from the foliage. The heavy excretion of wax that gives them a very fluffy appearance aids in their ability to float on the hot air currents or fly greater distances. They are specific to hackberry trees, and the foliage becomes black with sooty mold and dries up from the heavy feeding. The hackberry trees along the Interstate that appear to be dying are the result of the heavy feeding by the aphids. Several predators have been observed feeding on the populations, but the honeydew excretions under infested trees is very heavy. Vehicles, houses and outdoor furniture under infested trees are covered in the honeydew, and sooty mold develops very quickly. Pressure washing with soap will help to remove the honeydew, but you will have to scrub to get rid of the sooty mold. So once honeydew is noticed, wash it off and treat the trees with a systemic. Either sprays or granules can be used. Where granules are used, be sure to water it in to enhance response time. Figure 1. Lubber grasshopper – The large Eastern lubber grasshopper has been found in increasing number in the last few weeks. These large, black-and-orange grasshoppers with pink underwings can be a nuisance to homeowners and travelers. In yards they feed on a variety of plant and vegetable material, and on the roads in large numbers they can make the surface very slick when they are mashed on the roadway. When touched or bothered they will hiss and flare their wings in a show of defiance. The lubber grasshopper does not fly and simply walks or jumps when moving from one location to another. Management can be obtained using either Sevin or one of the pyrethroid sprays. Figure 2. June beetles – This is a little late for June beetles, but we have seen several areas with high populations and defoliation on trees and shrubs. This could possibly be due to the weather conditions – but that’s a guess. Although easily controlled, they can cause heavy defoliation and injury to plants. Sprays with Sevin will control the adults. It is important where these populations occur to check the lawns for grub infestations. Peel back a one-square-foot area and count the number of grubs observed. If you find more than five, a management program will be needed to control the population. Several materials are available for control of the grubs – Sevin, Merit, Talstar, Safari, Garant and Mach 2. Figure 3. Crape myrtle aphids – The second flush of crape myrtle aphids is beginning. So to keep your trees clean of sooty mold and green, now is the time to check your trees and keep the populations down. Sprays, granules or slurries can be used to treat the trees to protect them and keep them beautiful. Orthene, Cygon, Malathion and Merit are the available materials. Figure 4. Psocids – They’re a little early this year, but they’re webbing up trees all over the state. Usually not seen until late September, the psocids are actively encasing trees now. This webbing appears to be a fungal growth encompassing the wood surface of the trees, but in reality it is spun to create a microclimate for these busy little insects. They are feeding on organic matter on the surface of the trees and are actually cleaning the tree trunks for you. The webbing will cover the entire woody surface from the exposed roots on oaks all the way to the base of the leaves but will not get on the foliage. Many trees are infested by these little insects, and all get a free cleaning job. No treatment are necessary because once the weather cools the insects will be in the egg stage and the webbing will gradually break down and disappear. Figure 5. African honey bees – African honey bees continue to spread in Louisiana since they have now been found in LaSalle Parish. To keep up with the movements through Louisiana, check the AgCenter Web site, www.lsuagcenter.com , under bees and wasp for a map showing where they are and when they arrived there. Figure 6. Orange dog caterpillar – Those of us with citrus trees in our yards need to check for this greenish brown-looking caterpillar. The larva of the giant swallowtail, this odd-looking caterpillar resembles bird dropping when small. It has a unique feature – eversible glands that resemble a snake’s tongue. These two dark-orange glands are everted when the caterpillar is disturbed as a defense mechanism. It does not sting or burn but contains a vey pungent odor and when touched leaves your hand or finger with a very nauseating smell that is hard to wash off. They can be managed with just about any material from oils and soaps to insecticides. The biggest problem with management is that you can clean up your trees today and in a week or so the adults will visit the trees again and eggs starting the cycle over. If you see the adult visit your trees, you can go to the site and check for the small, pin-head-size eggs that are light green to pearl in color and simply remove them. The option is to watch for damage and then remove the larvae. Figure 7. Cicada killers – Once again these large wasps are flitting around over groundcovers and shrubs. Mostly what homeowners and business owners are seeing are the males chasing each other to keep them out of their nests. The female is busy flying about looking for cicadas to catch and sting and bring back to the nest as a food source for the next generation. These wasps live in burrows in the soil about 10 to 16 inches deep, only one pair to a burrow. At the base of the burrow the female digs several cells in which she places the paralyzed cicadas she catches and stings. She places two or three to a cell, deposits an egg and closes the cell, repeating this until the burrow is full. Although large and menacing, these wasps are very docile. Where they are in lawns, one can pass the lawnmower over the site and they will just fly around and return when you leave. If you stand still in an area where they are nesting in large numbers, they will on occasion land on you and preen themselves and then fly off. The female does sting but only if caught in clothing, stepped on with a bare foot, or accidently fallen on when playing or working outdoors. These are beneficial wasp and should be left alone. Figure 8. Until next month, Dale [Image: Hackberry aphid on leaf.] [Image: Lubber grasshoppers] [Image: June bugs and grubs] [Image: Aphids on foliage] [Image: bark lice webbing] [Image: African distribution in Louisiana] [Image: Orange dog caterpilar, adult and eggs.] [Image: cicada killer with cicada.]

Posted on: 7/18/2008 7:51:03 AM