Tsuga Search introduction   Will Blozan   May 16, 2006 18:30 PDT  ENTS, Many posts will be forthcoming regarding a project called the "Tsuga Search". I want to take this opportunity to introduce it and set the context for the work I am doing in the southern Appalachians. As most of you may know, I am passionate about trees and have a particular fondness for eastern hemlock. I spent three years working for the National Park Service mapping old-growth hemlock forests for Great Smoky Mountains National Park (GRSM). The project was helping resource managers prepare for the arrival of the dreaded hemlock woolly adelgid (HWA). This tiny insect is fatal to the eastern hemlock and threatens to extirpate it from the natural forests in the GRSM. (HWA kills Carolina hemlock as well but that species does not occur in GRSM.) Well, HWA was confirmed in GRSM in 2002 and has begun its deadly march into the old-growth hemlock forests- some of the most extensive and pristine in the southern Appalachians. The park contains many thousands of acres of ancient hemlock forests and hemlock is a crucial and common component of many of the other 500,000 acres of GRSM. The devastation will be cataclysmic in the pure hemlock forests, some of which can cover over 100 contiguous acres. The higher elevation hemlock forests have already experienced nearly complete loss of American beech to beech bark disease and any remaining trees of other species will likely be physically crushed and/or damaged by the huge, falling hemlocks. Ecosystem collapse can be expected as well as a complete conversion to another vegetation type of yet to be determined composition. Exotic plant encroachment will be a concern as will issues of water quality and the viability of invertebrate, amphibian and avian populations. Fortunately, GRSM has a full-time and aggressive team out combating the HWA using several tactics in an attempt to preserve some forests. The primary control method is a soil application of a systemic insecticide that is highly successful but somewhat costly. Foliar sprays are also employed as a control on easily accessed sites along roads and near buildings. Biocontrol has been ongoing for several years, with two species of predatory beetle released that feed exclusively on HWA. Positive results have yet to be observed from the biocontrol methods but chemically treated trees and groves are recovering. Unfortunately, funding is tight and HWA is winning the race to the more remote forests. Soil treatments are most effective when the trees are in good vigor, which is not the case for most of GRSM. However, I am confident that the treatments will make a huge impact on preserving some forests for people and wildlife to visit and utilize in the future. I commend their efforts and will sincerely appreciate the end result. NPS staff has routinely drawn upon the experience of ENTS members in the area and as such we experience a positive working relationship. Michael Davie and Jess Riddle are particularly well-traveled and knowledgeable of GRSM hemlock forests. My tree care company has been contracted to complete extensive soil treatments in the backcountry of the Cataloochee District (arguably the "epicenter" of eastern hemlock development) and as such have the working knowledge and practical experience of large scale old-growth hemlock preservation efforts. My interest in big trees is obvious and I have been documenting the giant hemlocks of GRSM beginning with my first climb of the tallest recorded eastern hemlock, the Tsali Hemlock (169'10") in 1998. I wanted to take this interest one step further and blend my passion for big trees with a desire to save these trees and forests for the future. My personal mission is to leave both a living legacy of exceptional hemlock forests for future studies and to gather benchmark data of a species and its environment on the verge of ecological extinction. The recent loss to HWA of the tallest known hemlock forest ever documented (East Fork Chattooga River, SC) hit home like a spear through my heart. I had to do something. The window for preservation was quickly closing- I had to do something now. Thus was born the "Tsuga Search". With the advice of Dr. Lee Frelich, Dr. Robert Van Pelt, Bob Leverett and Jess Riddle we proposed to GRSM a study of the superlative hemlock forests of GRSM and other known groves of exceptional trees. The general gist of it is: to locate, document and preserve exceptional specimens of eastern hemlock within GRSM. Searches for exceptional trees would be in areas known to hold good growth potential, and trees already discovered would be relocated and measured. Vegetation plots would be established and sampled around the trees and environmental parameters assessed. The trees would be climbed, measured for volume, photographed and treated with appropriate control measures to combat HWA. Core samples would be pulled from surrounding trees to evaluate stand age and perhaps disturbance history. The selected trees and surrounding groves would be treated for HWA in complement to the extensive preservation efforts of the NPS. To date, the project has been entirely funded by my company, Appalachian Arborists, Inc. Resource managers at GRSM have just submitted a proposal for a matching grant to offset some costs. The acceptance of this grant hinges on the incorporation and non-profit status of ENTS, another effort in the works. Once ENTS is established as its own entity with grant receiving potential, the Tsuga Search and other projects proposed by fellow ENTS can be funded. The project design can be adapted to other threatened species as well. The development of the macroscope volume technique was a direct result of the Tsuga Search, as the search for big trees naturally involves volume determination. We performed our first entire tree test of the technique last week. The macroscope volume was 1223 ft3 for a giant tree on eastern Winding Stairs Branch in Cataloochee. I climbed the tree and measured it "by hand" to 1180 cubic feet, a 3.5% difference. Jess and I were striving for ground based estimates to be within 5% of a climb. Of course, there is no way to be sure exactly how close the macroscope values are since the climb data are not an exact representation either. Jess and I delivered a poster at the recent old-growth forest conference that summarized the findings since October 2005. I will send a progress report to Ed to post. Check back soon on the "Hemlock Search" link on the ENTS website for the abstract, updates and photos. Will Blozan May 2006   Home