It’s cold outside, but the bugs are still around. The weather may have killed a few, but the vast majority is still kicking. A good example is the mosquitoes we have been seeing every time the sun warms us up a little.
1. Buck Moth Larva -- The populations usually begin to hatch in the lower part of the state the middle of the month. The eggs were laid in late fall and early winter on the small twigs of the oak trees. These black spiny caterpillars feed in clusters through the first four instars and then begin to move about independently, finishing their development and looking for a place to pupate on the ground in leaf litter. They will rest there until fall when the adults begin to emerge. They produce a vicious sting from the venom contained in the spines broken off in the skin when touched. Any basic solution will help ease the pain and help to keep swelling and burning to a minimum. (Figure 1.)
2. Forest and Eastern Tent Caterpillars -- These two caterpillars have been the scourge of the landscape the last two years. They have emerged with a vengeance and have eaten the foliage off many trees and created a mess around many homes and businesses. The egg masses that these caterpillars hatch from can be found now on many trees, especially live oaks and sweet gum. A good way to reduce some of the potential population is the check your trees and remove as many of these egg masses as possible. They appear as small brown crystalline bands around pencil-size or smaller branches and appear to have bubbles in them. These bubbles are the actual eggs in the mass; the brown mass around them protects them from environmental conditions and pesticides. Simply rub or pop them off and put in the trash. If dropped on the ground some will hatch and re-infest the tree. Where egg masses hatch and caterpillars are eating the foliage, sprays with pyrethroids like Bayer Advanced Garden with Cyfluthrin or Bengal spray with Deltamethrin or any of several other insecticides (Orthene, Warrior, Demon, Bt.) can be used. (Figure 2.)
3. White Grubs -- These are the larva of June beetles, chaffers and other beetles. They feed and damage the turf or grass in your yard. Although they do not begin to emerge until the soil temperature warms, tunneling or holes dug in the yard by opossums, raccoons, moles, coyotes and armadillos are good indication of a good-to-heavy population. The larva damages the grass, but the adults are foliage feeders on various trees and plants. The June beetles will strip the foliage off trees, and the chaffers will destroy rose and other blossoms. To check for infestations, cut three sides of a square foot of grass and peel the turf back. If 5 or more grubs are found, treatment may be necessary. If the lawn or field is well-maintained, the density of infestation may go as high as 15-20 grubs per square foot. Treatments include Sevin, Mach 2 and Merit but should not be made until the soil has warmed and the grubs are active. (figure 3.)
4. Earthworms -- This is a good organism until the population becomes extreme. Dense populations can cause the soil to become spongy and the grass to die out. After heavy rains, large masses of small earthworms can be found on sidewalks, driveways and streets. Where dense populations exist, it is best to treat with Sevin to reduce the population and make the remainder disperse. (Figure 4.)
5. Crane flies -- These large mosquito-like insects are harmless as adults. They are a nuisance to homeowners and businesses. Every time a door is opened, they fly in and fly around the lights or tap their bodies on lamp shades when at rest. The larva in dense populations can cause injury to grass. They are most often noticed when the larva pupate and the pupae work their way to the surface to allow the crane fly to emerge. These pupal cases are called leather jackets. (Figure 5.)
6. African honeybees -- We now have African honeybees in four parishes: Caddo, Calcasieu, Cameron and St. Bernard. Although we have not had any problems with African honeybees, be aware of colonies of bees. The Africans can be very aggressive when the colonies are disturbed. The problem is not in the venom but high number of stings and greater amount of venom that can be received from an African colony. Disturb a European colony and 50-100 bees will chase you 50 to 60 yards; disturb an African colony and 400 to 500 honeybees will chase you a mile or more. If you encounter a swarm of honeybee or a colony in a structure, contact a beekeeper from the list located at www.lsuagcenter.com, then click environment and natural resources and then scroll down to bees and wasps and click there. The list contains the names and phone numbers of beekeepers by regions of the state who remove swarms and bees from structures. Proper removal is necessary or other bees will return. (Figure 6.)
7. Aphids -- These little piercing sucking insects are out on daylilies. They are feeding in the whorls of the leaves, and both aphids and cast skins can be observed. If uncontrolled they will reduce plant growth and shorten the life of the blooms. The best management for these is to use a systemic material like Merit or Orthene and spray or drench around the plants. The weather is a little cool for beneficials to be about. If you collected some of the Asian lady beetles and stored them in your refrigerator, you could release some of them now rather than spraying. (Figure 7.)
8. pH -- This is an extremely important factors if you are spraying your plants with insecticides. Most water in the state has a pH of about 8.3. This makes it unusable for insecticide sprays. Most insecticides are acid-forming materials, and water with a pH of 8.3 is basic. Mixing the two would cause alkaline hydrolysis of the insecticide. This is a process in which the high-pH water breaks down the insecticide and you do not get the initial kill or residual from the insecticide as you should. The optimum pH for the water is between 5.5 and 6.5. In this range you have no breakdown of the insecticide, so you get the good initial knockdown from the spray and an effective residual, which reduces the number of sprays you have to make and is cost effective for you and environmentally safer. The pH should be checked before the addition of the insecticide at each spraying. This is because the pH of the water can change with temperature and with the amount of rainfall or drought. The best way to check pH is with a digital pH pen, although litmus paper or swimming pool test kits will work. The best way to modify the pH is with a buffer as it will lock in the pH and not permit temperature to break it down as it would with acid or vinegar. Not checking and adjusting the water pH is one of best ways to develop tolerance or resistance to an insecticide. We do not have enough materials available to us to lose any by not using it properly.
[Image: Buck moth larva]
[Image: Egg mass of Eastern and Forest tent catapillar]
[Image: White grubs]
[Image: Mass of young earthworms after rain from a dense population.]
| [Image: Crane fly adult and larva]
[Image: State map]
[Image: Daylily aphids]
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