Treesearch

Maintaining an appropriate seasonality is perhaps the most basic ecological requisite for insects living in temperate environments. The basic ecological importance of seasonality is enough to justify expending considerable effort to accurately model the processes involved. For insects of significant economic consequence, seasonality assumes additional importance because management decisions are often based on seasonal timing. In gypsy moth management, timing of BT applications and determining an efficient sampling interval for placement of pheromone traps are two such applications. We are,...

GypsES, a decision-support and expert system for the management of Gypsy Moth addresses five related research problems in a modular, computer-based project. The modules are hazard rating, monitoring, prediction, treatment decision and treatment implementation. One common component is a geographic information system designed to function intelligently. We refer to this component as an intelligent GIS, (IGIS). The IGIS is incorporated in a prototype GypsES package on a Macintosh computer. The paper discusses the issues in the design and development of IGIS with regard to the hardware and...

The gypsy moth is a serious threat to the hardwood forests of the eastern United States. Although chemical treatments currently exist which can be used to help control the impacts of the moth, silvicultural control measures are just now being proposed and tested. Felling and skidding cost estimates for harvesting merchantable timber under two such proposed silvicultural thinning treatments are reported. Costs for felling the nonmerchantable component of the thinnings in order to achieve treatment objectives are also discussed.

The gypsy moth is perhaps the most widely studied forest insect in the world and much of this research has focused on various aspects of population dynamics. But despite this voluminous amount of research we still lack a good understanding of which, if any, natural enemy species regulate gypsy moth populations. The classical approach to analyzing insect population dynamics is the collection of a series of life-tables, stratified over several generations at the same location(s). This type of approach is valuable for detecting temporal density-dependent mortality and delayed density-dependenc...

In 1987, we began a study to determine the relationships between gypsy moth growth and survival and forest site factors. The major objectives of this study were to determine the (1) relationships between gypsy moth survival and growth and different ecosystem conditions, (2) relationships among egg hatch, host phenology, and distribution of small larvae in the understory, (3) impact of leaf development age on gypsy moth growth and survival, and (4) role of host switching on gypsy moth growth and survival.

The potential for defoliation of oak seedlings by gypsy moth is quite high. We were interested in examining the interactions between various natural stresses and resulting gypsy moth feeding preferences and the results of defoliation stress on the growth and photosynthetic responses of the oak seedlings.

Traditionally, counts of egg masses have been used to predict defoliation by the gypsy moth. Regardless of the method and precision used to obtain the counts, estimates of egg mass density alone often do not provide satisfactory predictions of defoliation. Although defoliation levels greater than 50% are seldom observed if egg mass densities are less than 600 per hectare (250/acre), data from Melrose Highlands and the Intensive Plot System (IPS), as well as recent data from New Jersey and Pennsylvania, reveal that egg mass densities above this "threshold" result in damaging defoliation in...

The gypsy moth was accidentally introduced to North America near Boston by E. Leopold Trouvelot in 1869. Since that time, the range of the gypsy moth has slowly spread and the generally infested region presently extends as far as Ohio, West Virginia, Virginia and North Carolina. A separate isolated but expanding population exists in Michigan. The goal of this study was to quantify the process of gypsy moth spread through North America and relate the process to other landscape features. The ultimate purpose of this research is the development of sound predictions of future gypsy moth spread.

Leading edge gypsy moth populations have been the focus of several intervention programs (MDIPM, AIPM). Knowledge of gypsy moth population dynamics in leading edge area is crucial for effective management. Populations in these areas tend to reach outbreak levels (noticeable defoliation) within three to four years after egg masses are first detected. Pheromone traps have proven effective for detection and estimating population density in building populations. However, after populations have reached outbreak levels the utility of pheromone traps is decreased, primarily due to trap saturation....

Egg mass survey data from operational gypsy moth (Lymantria dispar L.) management programs in five Maryland county parks and the Beltsville Agricultural Research Center (BARC) have demonstrated that improved survey protocols are needed to increase the precision and accuracy of the surveys.