Sunday, May 17, 2009

Excess Rain Means Pesky Mosquitoes!

Due to the all of the April and May rainfall in Texas, we are now experiencing a higher population of another pest insect, the mosquito. Mosquitoes are a diverse group of flies that are found worldwide, with about 85 species living in Texas.
Mosquitoes develop through complete metamorphosis with an egg, larva, pupa and adult stage. Mosquito eggs may be laid individually or in clusters on the surface of water or in dry locations that will periodically flood. The eggs hatch into larvae that eat bacteria, fungi and other organic debris in the water. The larvae will develop into pupae, which do not feed. The adult stage will emerge from the water to take flight.
Adult male and female mosquitoes feed on nectar, honeydew and fruit juices. The female mosquito will consume blood in order to develop her eggs. This causes the female mosquitoes to be the most DANGEROUS ANIMAL in the world, since they are capable of transmitting such diseases as Malaria, West Nile Virus, Eastern Equine Encephalitis, and Yellow Fever worldwide.
Some Control Options Outdoors:
The number one way to reduce mosquito populations in your yard is source reduction! Mosquitoes need as little as a bottle cap full of water to complete their lifecycle, so all areas where water collects needs to be emptied or changed weekly. If standing water is eliminated in your backyard, then the overall mosquito population in your area will be reduced.
1) Areas containing water should be changed or emptied weekly, such as wading pools, buckets, bird baths, pet dishes, ponds, boat covers, irrigation systems, and French drains.
2) Holes or depressions in trees should be filled with sand or mortar.
3) Leaky pipes and faucets should be repaired.
4) For standing water that can not be drained, one suggestion is to use mosquito dunks containing Bacillus thuringiensis israelensis (Bti) to kill the mosquito larvae.
Mow tall grasses and reduce the amount of foliage to reduce the resting sites for adult mosquitoes. Insecticides can be applied to trees and shrubs, such as those containing permethrin, in order to kill adult mosquitoes.
Some Options To Prevent Mosquito Bites:
1) Avoid wearing dark colors, since mosquitoes use visual cues to locate hosts.
2) Avoid exercising or yard work in the heat of the day, since mosquitoes are attracted to carbon dioxide and perspiration.
3) Avoid wearing fruity or floral fragrances in perfumes, deodorants, hair products, or sunscreens, since these scents are more attractive to mosquitoes.
4) Wear long, loose-fitting clothing to avoid mosquito bites.
5) Chemicals can be applied to the skin to prevent bites. DEET, has been an effective repellent that can be applied to the skin to repel mosquitoes. There are also other mosquito repellents on the market such as picaridin, oil of lemon eucalyptus, oil of eucalyptus, and soybean oil-based repellents that can be applied to the skin.

Asian tiger mosquito, Aedes albopictus (Skuse) (Diptera: Culicidae). Photo by Dr. Bart Drees, Professor and Extension Entomologist, Texas A&M Univeristy.

Monday, May 11, 2009

Swarms of Bees

Swarms of bees occur most commonly during the early spring when new queens decide to form a new nesting site. These bee swarms are less likely to be aggressive so we usually do not have to worry about stinging. However, these swarms tend to cause uproars in urban areas, if the nest settles in a backyard tree or on a porch. Also if the bees find a way to invade structures and take up residence in walls or attics, it could lead to a pretty expensive removal. If nests are not removed, the wax, honey and dead bees may produce odors that can attract other pests such as mice, ants, or cockroaches.
Some people prefer to leave their wild bee swarms alone. However if you wish to take action, the safest course is to hire a beekeeper to remove the swarm or hire a professional to eliminate it before they discover a way into structures. For more information about bees, please visit

Monday, May 4, 2009

An Outbreak of Sawflies!

An outbreak of pine sawflies defoliating pine trees in Lamar, Kaufman and Hunt counties have been reported, mainly on the loblolly pine. Although its identity has not been confirmed, it is likely one of the Neodiprion species of pine sawflies. Different species of sawflies cause periodic, widespread defoliation of pines throughout the southern states. The leaves (needles) of infested pines may be chewed down to the fascicles at the base of the needle bunches.

Sawflies are the only suborder of wasps, in the order Hymenoptera, that are plant feeders. They are greenish in color with dark longitudinal stripes and orange to black heads.

According to the Texas Forest Service entomologists, Joe Pase and Dr. Don Grossman, most affected trees should recover and re-leaf with no treatment. According to Pase, “The larvae feed mostly on 2nd year needles and leave the current year’s growth intact. The result is that few trees die from the defoliation. When tree mortality occurs, it is usually from attacks by pine engraver beetles (pine bark beetles) responding to stressed trees. Even then, few trees are attacked by pine beetles. Because the new growth on the trees this year has not progressed very far, the trees look especially bad, but I think most of them will come through OK – they just need a little time for the new growth to develop.”

If you feel that chemical treatment is needed, then applications of carbaryl or a pyrethroid insecticide such as bifenthrin or permethrin are suggested. Note that B.t. and spinosad are not effective against sawflies, since they are not true caterpillars.

There is usually more than one generation a year, so watch for additional feeding in late May or June. Trees that have been previously attacked may experience re-infestation by the 2nd generation. However, diseases and natural enemies usually keep later sawfly generations under natural control.

Sources: Joe Pase III, Entomologist, Texas Forest Service, and
Mike Merchant, Texas AgriLife Extension Entomologist,

Photo by: Pam Corder, Kaufman County Urban Forester.