FLEP Technical Information for Foresters

Information Sheet for Foresters Updated - August 4, 2006

Using FLEP to Help Forest Landowners Improve Forest Health Conditions before Possible Sirex Woodwasp Infestation

The following information is intended for foresters and other natural resource professionals involved in providing services to forest landowners with a concern or need to address potential Sirex Woodwasp infestation in pine stands.

Concurrence of the State Forest Stewardship Coordinating Committee has been secured by New York's State Forester, to amend the State Priority Plan for the implementation of the Forest Land Enhancement Program, to target funding to address opportunities to enhance forest health. Such monies will be available to develop silvicultural prescriptions and non-commercial thinning of forest stands potentially at risk of Sirex infestation. Funds will be targeted to a geographic area and adjoining counties where Sirex noctilio has been detected. New York's FLEP authorizes cost share payments, up to 75% of the actual cost not to exceed established caps, for the installation of eligible sustainable forestry practices.

The purpose of this information sheet is to reach out with educational material to foresters and others. This information should be valuable in discussing management alternatives with forest owners. It provides general silvicultural information appropriate to address the threat of Sirex regardless of the availability of FLEP financial assistance.

Persons requiring additional information about the availability of FLEP or the status of Sirex Woodwasp, should contact their local DEC Forestry office.

Background

Sirex noctilio, European Woodwasp, an invasive insect has been discovered in at least fifteen central and western New York counties. Sirex Woodwasp infests various species of pines which generally results in tree mortality. Unhealthy, stressed trees growing in overcrowded conditions are much more prone to infestation, damage and mortality. The female Woodwasp chooses unhealthy pines, injecting a toxic mucous and symbiotic fungus, when laying their eggs. The fungus and toxins working together can kill trees in a short period of time, creating a suitable environment for larval development.

The Sirex Woodwasp is known to attack many species worldwide including white, red, Scotch, Austrian, loblolly, Monterey, jack, slash and shortleaf pines. White, red and Scotch pine have been planted extensively while white and red pine are common components of natural forests in New York.

Healthy, fast growing, well managed pines are more capable of resisting Woodwasp infestation. Forest management actions around the world to address Sirex Woodwasp concern have included non-commercial thinning as well as commercial selection harvesting of pine stands removing stressed, overcrowded and unhealthy trees, retaining healthy dominant trees.

Literature on Sirex from around the world, including Australia, indicates that larger, dominant trees in managed / thinned stands experienced very little to no damage from Sirex noctilio. Unhealthy, suppressed and over crowed trees in unmanaged stands, on the other hand, experienced mortality rates of up to 65% over a period of time in one study. These patterns have been suggested as to likely to occur in North American pine stands.

FLEP Status

During July 2006, $46,678 was secured by New York for use for FLEP cost share assistance to implement sustainable forestry practices on non-industrial private forest land. These funds are intended to help forest owners implement management recommendations in their Forest Stewardship Plans.

The State Forester received consensus from the State Forest Stewardship Committee to target the above funds to practices to address the potential occurrence of Sirex in pine stands.

FLEP is due to terminate in 2007 as congressional authorization for the program ceases at that time. This time line provides ample opportunity for interested landowners to complete work on the ground to reduce susceptibility to Sirex infestation.

FLEP 7 Eligibility Requirements

The following requirements are being considered for eligibility to request dedicated financial assistance funding for the thinning/stand Improvement practice under FLEP 7, Forest Health and Protection, to address Sirex issues:

eligible stands must be a softwood forest type consisting of at least a 60% component of one of the following species or combination thereof - Scotch, white, red, pitch, jack or Austrian pines on land exhibiting a site index of 60 or greater for the dominant species,
consist of at least 3 contiguous acres,
current stocking level must be at least 80% determined pursuant to an applicable stocking guide relevant to the dominant forest type,
the tract on which the stand is situated must exhibit High or Medium Stewardship Potential as documented by New York's Stewardship Analysis Project maps.

Practice implementation standards

The following are being considered as standards and procedure for installation of practice:

A stand analysis based upon a recognized stocking guide for the forest type must be conducted
A prescription to reduce stocking to no more than 70% in previously unmanaged stands and 60% in managed stands will be prepared for approval by DEC
Trees will be designated / marked for implementation of the approved prescription
Stands that are to be thinned / cut on a non-commercial basis must have work completed before authorization is made for cost share payment for prescription development and thinning work
Stands to be treated commercially must be harvested in compliance with the DEC approved prescription and tree designation. Owners failing to commence commercial harvesting within 12 months of receiving a cost share payment, per approved prescription will be required to reimburse the program of payment(s) received. Cost share is NOT authorized for sale advertising, contract preparation, sale supervision or any other action not directly connected to the development and application of a silvicultural prescription and tree designation

Suggested stocking guides for reference purposes include of the following:

A Silvicultural Guide for White Pine in the Northeast - K. Lancaster & W. Leak Technical Report NE-41
Revised White Pine Stocking Guide for Managed Stands - K. Lancaster & N. Lamson, USDA NA TP 01-99
Red Pine in North Central States - J. Benzie, USDA Gen. Tech Rept. NC-33
A Revised Managers Handbook for Red Pine in the North Central Region - D. Gilmore & B. Palik, USDA Gen, Tech. Rept. NC-264
Jack Pine in the North Central States - J. Benzie, USDA Gen. Tech. Rept. NC-33

Important Considerations

Foresters often must consider specific site conditions and customize prescriptions, but some general recommendations should be used as follows:

Basal area for red pine is best maintained at 100 ft2 per acre (or slightly lower) for optimal individual tree growth and vigor (Benzie 1977a, Gilmore and Palik 2006).
For previously unthinned white pine, basal areas less than 150 ft2 per acre would promote optimal individual tree growth and vigor (Lancaster and Leak 1978). Stocking levels below 125 ft2 per acre of basal area can be used for previously managed stands of white pine (Leak and Lamson 1999).
For jack pine, optimal stand density would be between 110 and 140 ft2 per acre for optimal individual tree growth (Benzie 1977b).

To maximize individual tree growth and vigor, lower basal areas than listed above may be appropriate. Potential host trees exhibiting poor health and low vigor should be removed.

It is critically important NOT to conduct thinning or harvesting operations during the Sirex flight period of May to October. If there are no other alternatives and work must be conducted during this period, steps should be taken to remove or destroy potential breeding material in logging debris. Chipping or whole tree utilization should be considered.

As it may take the stand up to a year to recover from disturbance related to thinning or harvesting it is important the stand be treated before a problem is evident.