11-12-13-WS - Laserfiche WebLink

Home Browse Search

authors or has been consistently effective for of imidacloprid are very similar. Homeowners EAB control. Please see the following sec-apply the same amount of active ingredient that professionals apply. However, there are from these trials. Results of some tests have certain restrictions on the use of homeowner also been posted on www.emeraldashborer.formulations that do not apply to professional info.formulations. Homeowner formulations of imidacloprid can be applied only as a drench. Strategies for the most effective use of these It is not legal to inject these products into the insecticide products are described below. It soil, although some companies have mar- is important to note that pesticide labels and registrations change constantly and vary from this purpose. Homeowners are also restricted state to state. It is the legal responsibility of to making only one application per year. the pesticide applicator to read, understand Several generic products containing imida- and follow all current label directions for the cloprid are available to homeowners, but the . formulations vary and the effectiveness of these products has not yet been evaluated in university tests. Using Insecticides to Soil drenches offer the advantage of requir- Control EAB ing no special equipment for applica- tion other than a bucket or watering can. Soil-Applied Systemic Insecticides However, imidacloprid can bind to surface layers of organic matter, such as mulch or leaf Systemic insecticides applied to the soil litter, which can reduce uptake by the tree. are taken up by the roots and translocated Before applying soil drenches, it is impor- throughout the tree. The most widely tested tant to remove, rake or pull away any mulch soil-applied systemic insecticide for control of or dead leaves so the insecticide solution is EAB is imidacloprid, which is available under poured directly on the mineral soil. several brand names for use by professional applicators and homeowners (see Table 1). Imidacloprid formulations labeled for use by All imidacloprid formulations can be applied professionals can be applied as a soil drench as a drench by mixing the product with water, or as soil injections. Soil injections require then pouring the solution directly on the soil specialized equipment, but offer the advan- around the base of the trunk. Dinotefuran tage of placing the insecticide under mulch was recently labeled for use against EAB as a or turf and directly into the root zone. This soil treatment (in addition to its use as a basal also can help to prevent runoff on sloped trunk spray discussed below). Studies to test surfaces. Injections should be made just deep its effectiveness as a soil treatment are cur- enough to place the insecticide beneath the rently underway in Michigan and Ohio. soil surface (2-4 inches). Soil injections should be made within 18 inches of the trunk where Imidacloprid soil applications should be . As you made when the soil is moist but not satu- move away from the tree, large radial roots rated. Application to water-logged soil diverge like spokes on a wheel and studies can result in poor uptake if the insecticide have shown that uptake is higher when the becomes excessively diluted and can also product is applied at the base of the trunk. result in puddles of insecticide that could There are no studies that show that applying wash away, potentially contaminating surface fertilizer with imidacloprid enhances uptake waters and storm sewers. Insecticide uptake or effectiveness of the insecticide. will also be limited when soil is excessively dry. Irrigating the soil surrounding the base Optimal timing for imidacloprid soil injec- of the tree before the insecticide application tions and drenches is mid-April to mid-May, can improve uptake. depending on your region. Allow four to six weeks for uptake and distribution of the The application rates for the homeowner insecticide within the tree. In southern Ohio, TM product (Bayer Advanced Tree & Shrub for example, you would apply the product by Insect Control) and professional formulations 6 INSECTICIDE OPTIONS FOR PROTECTING ASH TREES FROM EMEORER