Publications

 

Recent Submissions

  • Assessment of paper birch trees tapped for sap harvesting near Fairbanks, Alaska
    Trummer, Lori; Malone, Tom (United States Department of Agriculture, US Forest Service Alaska Region, State and Private Forestry Forest Health Protection, Anchorage Office, 2008-01)
    With increased growth in the birch sap extraction industry, the need for assessments of tree health and sustainability of birch tapping practices also grows. Site visits and evaluation of tapping practices were conducted at two commercial harvest locations in the Fairbanks area, Eva Creek in Ester and Cache Creek near Murphy Dome in 2007. In this evaluation we report on walk through observations and a pilot dissection study of tapped trees at each location. Numerous improper tapping practices are reported as well as breach of the Alaska Birch Syrupmakers’ Association (ABSA) “Best Practices Guidelines for Tree Tapping”. There will be a companion biological evaluation to this site visit report produced in 2008 by the same authors that will review the “Best Practices” guidelines developed by the ABSA and evaluate impacts to paper birch trees tapped for sap harvesting in Alaska.

  • Site Index of Balsam Poplar/Western Black Cottonwood in Interior and Southcentral Alaska
    Shaw, John D.; Packee, Edmond C. (1998-12)
    Stem analysis data were obtained from 268 balsam poplar (populus balsamifera L.) and black cottonwood (P. trichocarpa Torr. & Gray) trees on 67 sites in interior and southcentral Alaska during 1988-1990 for the purpose of height and volume growth analysis. A modifiedform of the Chapman-Richards growth model was used to produce polymorphic site index curves. Wide variations in curve shape, which were evident in region-to-region comparisons, required stratification ofthe data. Site index curves for balsam poplar north ofthe Alaska Range were produced using one equation and data from 35 sites. The remaining 32 sites, located south ofthe Range, were divided by landform (fluvial vs. upland). Sites on the middle and upper Susitna and Chulitna Rivers were placed in a separate fluvial class, giving three equations for sites south of the Range. The four equations produce the first polymorphic site index curves for poplars in Alaska. North. 1. Appl. For. 15(4):174-181.

  • Some impacts to paper birch trees tapped for sap harvesting in Alaska
    Trummer, Lori; Malone, Tom (United States Department of Agriculture, US Forest Service Alaska Region, State and Private Forestry Forest Health Protection, Anchorage Office, 2009-05)
    As the non-timber forest products industry increases on a commercial scale, the need for assessments of tree health and sustainability of these practices also increases. Harvesting birch sap for subsistence purposes has occurred for decades but commercial interests in this process and resource is expanding. In this evaluation, we review literature related to birch sap harvesting practices, report on a pilot study that assessed impacts to birch trees from sap harvesting, and review the “Best Practices” guidelines for tree tapping developed by the Alaska Birch Syrupmakers’ Association.

  • White Spruce Regeneration on a Blade-Scarified Alaskan Loess Soil
    Packee, Edmond C. (1990-09)
    Following hardwood removal from a mixed spruce-birch-aspen forest stand, portions of the stand were blade-scarified to encourage natural white spruce regeneration. Six years after treat­ment the number and height of white spruce seedlings were significantly greater on scarified than on unscarified plots. Whereas 100% of scarified sample plots contained five or more seedlings, 73% of unscarified plots contained no seedlings. Exposure of mineral soil and removal of grass competition are essential for the sat­ isfactory natural regeneration of white spruce. Detailed regeneration surveys should not be considered for white spruce until seedlings are 15 em tall, typically the fifth or sixth year after site preparation.

  • Total and Merchantable Volume of White Spruce in Alaska
    Malone, Thomas; Liang, Jingjing; Packee, Edmond C. (Society of American Foresters, 2012-12-20)
    White spruce (Picea glauca [Moench] Voss) is a valuable commercial species found in interior and southcentral Alaska. Numerous regional and local volume tables or equations exist; however, no statewide model exists or has been tested for accuracy. There is a demand for an accurate model to determine the cubic-foot volume of white spruce trees in Alaska. Multiple models were developed for white spruce to estimate total and merchantable cubic-foot volume to a 2-, 4-, and 6-in. top. These multiple-entry (diameter and height) models were developed for both inside and outside bark volume from a 6-in. stump. The models were tested on a regional basis at various geographic locations and were shown to be highly accurate. The Alaska models chosen have R2 at or near 0.99 and mean square error from 0 to 0.16 for all models. These models are shown to be superior to other white spruce models in Alaska.

  • A Bark Thickness Model for White Spruce in Alaska Northern Forests
    Malone, Thomas; Liang, Jingjing (Department of Forest Sciences, University of Alaska Fairbanks, 2009)
    Here we developed a simple linear model to estimate white spruce bark thickness in the northern forests of Alaska. Data were collected from six areas throughout interior and southcentral Alaska. Geographic variation of bark thickness was tested between the Alaska statewide model and for each geographic area. The results show that the Alaska statewide model is accurate, simple, and robust, and has no practical geographic variation over the six areas. The model provides accurate estimates of the bark thickness for white spruce trees in Alaska for a wide array of future studies, and it is in demand by landowners and forest managers to support their management decisions.