“WHAT’S HAPPENING?”
The University of Tennessee/Agricultural Extension Service
Entomology & Plant Pathology - EPP #60
March 16, 2007
GET READY FOR SPRING PEST CONTROL ON ORNAMENTALS
By Frank A. Hale
April and May are busy months for nursery growers and landscape professionals. A myriad of laborious tasks arise plus most insect and mite pests become active and many require some type of control. Late winter is the perfect time to be proactive and address some of the pest problems before it gets too busy.
One particularly effective pesticide to use during this delayed dormant period is horticultural oil. The overwintering eggs of spruce spider mite can be controlled with horticultural oil sprays on arborvitae, juniper, false cypress, spruce and other conifers. Southern red mite eggs are found on the underside of the leaves of broadleaf evergreens such as cherrylaurel, azalea, and holly. If good coverage is achieved, very few mites will hatch in April to feed on the foliage of infested plants.
Horticultural oil also does not leave an insecticide residual like many other insecticides that could kill beneficial insects (particularly parasitoid wasps) and mites for days or even weeks. This is extremely important with scale insects, whose populations are often regulated in nature by parasitoid wasps and other beneficial insects. Horticultural oils are particularly effective in controlling scale insects that are producing eggs in this delayed dormant period. Some of the oil can get underneath the scale cover and kill many of the eggs. Euonymus scale is an armored scale which produces eggs beneath its waxy cover that will hatch soon after the new spring growth occurs in evergreen euonymus cultivars. While a delayed dormant spray will kill many of the eggs, a follow-up spray will still be needed in April once the crawlers move to the new foliage.
Some systemic neonicotinoid insecticides can be applied to the soil in the winter so that they are absorbed by the roots to translocated up into the new foliage in the spring. Thiamethoxam (Flagship ), clothianidin (Arena 0.25 G), and imidacloprid (Merit 2F, Merit 75 WSP, Merit 2.5G, Marathon 1 G, Marathon 60 WP, Bayer Advanced Tree and Shrub Insect Control, and many other brands) and combination insecticides which include imidacloprid with a pyrethroid insecticide (Allectus SC, Discus) can be applied to the soil now to control many pests in the spring. Arena 0.25 G can be used to control aphids, azalea lace bug, caterpillars, Florida wax scale, Japanese beetle adults, leafhoppers, leafminers, mealybugs, whiteflies, root weevils and other listed pests. The Flagship 25 WG label lists aphids, lace bugs (azalea lace bug, hawthorn lace bug and others), soft scales, leafhoppers, hemlock woolly adelgid, sawflies and other pests. Insecticides containing imidacloprid are also effective in controlling the pests just listed for Flagship 25 WG plus several others such as Japanese beetles, leafminers (boxwood leafminer and others) and flatheaded borers.
Flatheaded borers attack most of our common landscape trees and can be very damaging, especially for the first three or four years after transplanting. Preferred hosts include maples, boxelder, crabapple, dogwood, oaks, sycamore, cherry, plum, hickory, pecan, walnut, poplar, willow, beech, chestnut, chinkapin, horsechestnut, linden, mountain-ash, serviceberry, elm, hackberry, hawthorn, redbud, and persimmon. Many other trees can also be attacked The systemic insecticide, imidacloprid, kills the flatheaded borer larvae before they can inflict serious damage by devouring the cambium beneath the bark and tunneling into the heartwood.
Dinotefuran (Safari) is another new systemic neonicotinoid insecticide. It is very water soluble and much more effective in controlling armored scale than imidacloprid and thiamethoxam. It could be used as a late winter drench for control of armored scale such as euonymus scale, white peach scale, oystershell scale, and pine needle scale.
CHAGAS DISEASE REPORTED IN LOUISIANA
ByDarrell Hensley
Chagas Disease was detected in a (74-year-old female) patient in rural New Orleans, Louisiana in July 2006. The patient had positive test results from two serologic tests and hemoculture; 56 percent of 18 kissing bugs (Triatoma sanguisuga) collected from the house of the patient were positive for T. cruzi by PCR.
Chagas disease (also called American trypanosomiasis) is a human parasitic disease which generally occurs in South America. Its pathogenic agent is a flagellate protozoan named Trypanosoma cruzi, which is transmitted to humans and other mammals mostly by assassin bugs of the subfamily Triatominae (Family Reduviidae). These insects are known by numerous common names varying by country, including benchuca, vinchuca, kissing bug, chipo and barbeiro. The most common insect species belong to the genera Triatoma, Rhodnius, and Panstrongylus. Other forms of transmission are possible, though, such as ingestion of food contaminated with parasites, blood transfusion and fetal transmission.
Trypanosoma cruzi is a member of the same genus as the infectious agent of African sleeping sickness, but its clinical manifestations, geographical distribution, life cycle and insect vectors are quite different.
Only five autochthonous cases of infection with the Chagas disease parasite have been reported in the United States: 3 in infants in Texas, 1 in an infant in Tennessee, and 1 in a 56-year-old woman in California. The most important triatomine species in the United States for Chagas disease transmission are Triatoma sanguisuga, [for photo see: <http://www.rso.cornell.edu/bugclub/images/Triatoma%20sanguisuga.jpg> -
Source: Dorn PL et al. Emerg Infect Dis, April 2007 [edited]
<http://www.cdc.gov/EID/content/13/4/605.htm>
REGIONAL INSECT TRAPPING SYSTEM
By Russ Patrick
A trapping system in conjunction with the University of Tennessee, University of Kentucky and University of Illinois has been set in motion through a SR-IPM grant funding travel and equipment for 2007. Traps in Tennessee have been located at the Research and Education Center in Jackson and Milan Experiment Station. Insects that are being studied are: Black cutworm, European Corn Borer, True Armyworm, Fall Armyworm and the Southwestern Corn Borer. Weather data will be collected and numbers of moths from Cone Traps and Bucket Traps. Hopefully, this system will become an early warning system for growers, agents and Agribusiness personnel. Data will be posted weekly at a website which I will send to you.
OTHER UT NEWSLETTERS WITH PEST MANAGEMENT INFORMATION
http://web.utk.edu/~extepp/fpn/fpn.htm
Tennessee Crop and Pest Management Newsletter
http://www.utextension.utk.edu/fieldCrops/cotton/cotton_insects/ipmnewsletters.htm
This and other "What's Happening" issues can be found at http://web.utk.edu/~extepp/whatshap.htm
Disclaimer
This publication contains pesticide recommendations that are subject to change at any time. The recommendations in this publication are provided only as a guide. It is always the pesticide applicator's responsibility, by law, to read and follow all current label directions for the specific pesticide being used. The label always takes precedence over the recommendations found in this publication.
Use of trade or brand names in this publication is for clarity and information; it does not imply approval of the product to the exclusion of others that may be of similar, suitable composition, nor does it guarantee or warrant the standard of the product. The author(s), the University of Tennessee Institute of Agriculture and University of Tennessee Extension assume no liability resulting from the use of these recommendations.
Precautionary Statement
To protect people and the environment, pesticides should be used safely. This is everyone’s responsibility,
especially the user. Read and follow label directions carefully before you mix, apply store or dispose of a pesticide. According to laws regulating pesticides, they must be used only as directed by the label.
Persons who do not obey the law will be subject to penalties.
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