Proceedings. National Gypsy Moth Review. of the. Charleston, W. Va. Nov , 1984

Transcription

1 Proceedings of the 1984 National Gypsy Moth Review Charleston, W. Va. Nov , 1984

2 PROCEEDINGS OF THE NATIONAL GYPSY MOTH REVIEW AT MARRIOTT HOTEL CHARLESTON, WEST VIRGINIA NOV HOSTED BY WEST VIRGINIA DEPARTMENT OF AGRICULTURE PLANT PEST CONTROL DIVISION GUS R. DOUGLASS - COMMISSIONER CAPITOL BUILDING CHARLESTON, WV AND SPONSORED BY THE NATIONAL GYPSY MOTH MANAGEMENT BOARD JAMES NICHOLS, CHAIRMAN 1984 PROGRAM COMMITTEE CHAIRMAN - ALAN R. MILLER WEST VIRGINIA DEPARTMENT OF AGRICULTURE PLANT PEST CONTROL DIVISION MEMBERS - DR. JACK COSTER - WEST VIRGINIA UNIVERSITY DIRECTOR SCHOOL OF FORESTRY DR. JOHN WEIDHASS - EXTENSION ENTOMOLOGIST VPI AND SU BOB TICHENOR - MARYLAND, DEPARTMENT OF AGRICULTURE MEETING ARRANGEMENTS ALAN R. MILLER - WEST VIRGINIA DEPT. OF AGRICULTURE

3 RESEARCH ON SILVICULTURAL OPTIONS FOR THE GYPSY MOTH 1 Kurt W. Gottschalk With the creation of our Research Work Unit (RWU) titled "Silvicultural Options for the Gypsy Moth" in April 1983, a new dimension was added to the Northeastern Forest Experiment Station's gypsy moth research program. Approval of the RWU's mission and research problems in July 1984 has defined the research program that we are pursuing. This program includes work by project scientists as well as cooperative efforts with universities, private industry, and government agencies. The project's mission is to provide silvicultural options and management guidelines for reducing damage associated with gypsy moth defoliation in northern hardwood and oak-hickory forest types in the eastern United States. Within this mission, we have identified three major problem areas. Before I discuss these problem areas, there is one other research area I want to mention. Under the Forest and Gypsy Koth objectives in the Station's Gypsy Moth Research Program for which our project is responsible is a section on "foci" area research. We presently have two cooperative agreements that are looking at the dynamics of gypsy moth and natural enemy populations within susceptible forest stands or foci. Mike Raupp at the University of Maryland and Bill Ravlin at VPI&SU are conducting these investigations. Their objectives are to identify and characterize stands that have the greatest likelihood of serving as gypsy moth foci, to establish gypsy moth population monitoring programs on these sites, and to quantify and evaluate the natural enemies of the gypsy moth on these sites. The University of Vermont, Cary Arboretum, and the University of Massachusetts are also working on foci research in cooperation with Wallner's project in Hamden. Problem 1: Impacts of Gypsy Moth on Forests The impacts of gypsy moth defoliation on forests occur in a variety of ways. The major impact that we are concerned with is loss of timber (see Dooley's manuscript). Timber losses have several aspects. The most obvious and immediately important during initial defoliation is mortality of commercial trees. We are quantifying timber mortality on the Tuscarora State Forest in Pennsylvania and Cacapon State Park in West Virginia. Additional information will be presented on these studies this afternoon. Ray Hicks of West Virginia University has two cooperative agreements with us looking at site and stand characteristics which are associated with mortality losses and development of prediction equations for mortality. Ray will be presenting more information on these projects this afternoon. We plan to initiate work on the secondary organisms that actually cause the mortality following gypsy moth defoliation. 1 Research Forester, USDA Forest Service, Northeastern Forest Experiment Station, P. O. Box 4360, ~brgantown, WV

4 Another timber loss is the growth loss that occurs on defoliated trees that do not die. Ray Hicks is looking at growth losses in bis plots as well as mortality. A third loss is quality loss in live trees due to false growth rings, crown dieback, and epicormic branching and in dead trees due to decay and wood boring insects. I shall come back to this topic later. The last timber loss involves loss of regeneration capacity due to lower seed production, loss of stump sprouting potential (due to low vigor and tree mortality) and mortality of advance regeneration. Ray Hicks is collecting information on regeneration in bis plots and I am collecting data in this area also. In the long run, this loss may be the most serious impact of gypsy moth on the forest. Non-timber losses are associated with recreation, aesthetics, wildlife habitat, and water quality. At the present time, we do not plan to start any studies to evaluate these losses. The final research area in problem one involves gypsy moth interactions with other defoliators. Linda Butler of WVU is working on collecting and identifying native defoliators that are present and competing with the gypsy moth. She will talk about her work this afternoon. Problem 2: Silvicultural Practices We know very little about the potential of silvicultural practices to reduce or minimize gypsy moth impacts. Silvicultural practices could work under two major strategies. The first is alteration of habitat for the gypsy moth and its predators, parasites, and diseases. These habitat alterations could have positive or negative effects in gypsy moth populations. The second strategy is alteration of stand susceptibility to gypsy moth defoliation (reducing its likelihood of defoliation) or stand vulnerability (reducing the mortality that occurs after defoliation). These alterations also have the possibility of positive or negative effects. Our major effort is focused on the second strategy. There are two approaches to silvicultural treatments. The first one involves intermediate stand treatments in existing stands. I have started research that is looking at the effects of commercial thinnings and commercial thinnings with TSI of saplings on mortalilty and growth loss as compared to uncut stands. Preliminary results suggest an increase in mortality in stands that have been thinned just prior to or shortly after defoliation occurs. I am also monitoring the advance regeneration survival and growth in the thinned and uncut stands. We plan on starting work that will examine the secondary organism population responses in thinned versus uncut stands. Another intermediate stand treatment that is of major importance is salvage cutting. In order to profitably salvage dead trees in a stand, we need to know how long after death that the trees are usable for lumber and pulp products. Dave Donley has looked at the wood borers that invade dead trees and this information will be presented later this afternoon. Also, we have funded cooperative research at Pennsylvania State University with Bill Merrill looking at the biodeterioration of oaks. Bill is identifying the organisms involved in and the rate of progression of decay in standing dead trees as well as examining some of the wood boring insects. We have also funded research at Penn. State on the pulping characteristics of dead trees. Bob Baldwin and Pete -97-

5 Labosky were involved. Initial results of their work and that of Hammermill Paper Company indicate that pulping characteristics of dead trees do not suffer losses as rapidly as lumber recovery. Penn. State had previously examined lumber recovery from dead trees and Pete will discuss that work later today. The second area involving silvicultural practices is regeneration treatments. The impact of gypsy moth defoliation on stand regeneration may make a difficult task impossible. I have established shelterwoods and clearcuts shortly after gypsy moth defoliation. Initial results suggest a significant effect on stump sprouting - both loss of vigor of stump sprouts and loss of sprouting due to mortality of trees. Excessive deer browsing interacts with defoliation stress by further reducing vigor and allowing Armillaria mellea to kill the sprouts. We plan to initiate work on the effects of gypsy moth defoliation on seed production as well. Problem 3: Decision-Support System Our final problem area consists of the process of integrating stand protection strategies and forest pest management into forest resource management programs. Our development of a decision-support system is based on a simulation model of the forest/gypsy moth ecosystem that will allow evaluations of alternative gypsy moth control strategies. Kathy Sheehan will now go into further detail on our model developmental efforts. -98-