Hemlock and Adelgid Survey    Edward Frank    Jan 22, 2007 21:21 PST  Fellow ENTS, I wanted to update you on a project on which I have been working. In early November, spurred by a casual comment that Will Blozan made, I conceived an idea of sending out a survey to major public and private landowners across the range of the Eastern and Carolina Hemlock asking about the presence of hemlock and the status of the hemlock wooly adelgid at each location. I sent draft copies of the proposed survey to Will and Jess Riddle asking what they thought of the idea. I received some comments, revisions, and additional questions in response. I started to send out the survey in January 2007 via email. The cover letter and survey documents are on the ENTS website: the full survey can be downloaded from our website at: http://www.bluehost.com/cgi-bin/uftp/?domain=ftp@nativetreesociety.org&password=anon under the title “Hemlock Survey.doc” (The address will likely wrap and may need to be pasted into the browser as two separate pieces.) Many park sites did not have an available email address, but ask that you fill out an online question form. I filled out the forms and either submitted a version of the cover letter or both the documents. I estimate I have sent out about 700 copies of the survey at this juncture. I am still sending some out as I get suggestions for additional referrals.   There is a deadline of February 28 for completing and returning the form. At this point I have received a number of responses to the survey from across the area. I expect more to come in as the deadline approaches. Some agencies have been more responsive than others. The National Park Service personnel have been particularly helpful. Valley Forge for example answered the survey in detail, sent some additional reports, and digital photos. I forwarded copies of these on to Scott Wade. Perhaps he will be able to get out to the park and get some good measurements of the hemlocks there. Other agencies have been more bureaucratic and collectivist in their responses. The major purposes of the survey was to gather site specific information at each location and collect personal observations, experiences, and comments from the people in the field at each of these locations. At this stage of the HWA infestation there have been several conferences, and I would be buried in paper if I printed all of the materials generated by researchers. I have read much of what is available online on the infestation. Most are compilations on a broad scale, general overviews, and summaries. What is lacking in these documents are site descriptions and personal observations by people actually working at these sites on a daily basis. That is what I am trying to generate with this survey. I have had many useful responses from people in many states toward this goal. Many eyes can sometimes see things that are missed in the broad overviews. Secondary goals are to gauge the preparedness of each site for the HWA arrival or to characterize the response to the active infestation at this time, and to find if the people managing these areas are knowledgeable about the hemlock resources present on the sites. If ENTS people would like to participate in the project, they are encouraged to add their own observations of the character of the HWA infestation. All places responding to the survey will be sent a copy of the report compiled from this data or a download link to get the document. (Don Bragg - when finished and revised, etc. could you convert it to pdf?) I am unsure of the ultimate dispensation of the report. It will be available on the ENTS website, perhaps it could be presented at one or more HWA conferences, or even the first refereed paper in the Bulletin of the Native Tree Society. Compiling the data at the end will be a task if we get a good response. Many of the questions have numerical or yes/no answers. These can be compiled on a large spreadsheet. Narrative answers - I will need to see. I am hoping the answers will fall into self sorting categories. As for the role of various ENTS in the analysis process - in a final report we should have a section on ground truthing the survey results. Many of you have visited a number of these sites and can see if the survey answers roughly correspond to your observations.   I shall also welcome at the time comments from others on interpretation of the results. Thank You, Edward Frank Re: Hemlock and Adelgid Survey   John A. Keslick, Jr.   Jan 23, 2007 04:03 PST  Ed Good Day, I always wonder if the trees are placed in a predisposition from fragmentation. Take into consideration the report that - "Hemlocks of sawlog size are notoriously subject to ring-shake, to radial stress, cracks, and , following sudden exposure, to sunscald of the bark, and to death. [sunscald is a poor term. JAK] These reactions may be the result of many adverse effects associated with changed regime of solar heat and soil moisture and culminate in a decline often referred to as post-logging decadence. When hemlocks are left as residual trees following partial cutting, and when they are exposed, through road or other construction or clearing, they often die, even when their root area is covered with understory brush. Eastern Hemlock is also considered to be one of the species most sensitive to sulfur fumes from smelters. An interesting type of ring-shake follows sapsucker injury." Source: Disease of Forest and Shade Trees of the United States, George H. Hepting, July 1971 page 488-489 I would have to say that any place I have seen adelgids. the area has been altered. I wonder what the adelgid situation is in large tracks of old grow with no roads? I think I will place the first section on each species of tree, from the reference, on the tree dictionary site. Sincerely, John A. Keslick, Jr. Re: Hemlock and Adelgid Survey   Andrew Joslin   Jan 23, 2007 05:26 PST  I haven't looked at Eastern Hemlock and HWA in old-growth but I've observed sites in eastern Massachusetts that are undisturbed hemlock groves. It appears that adelgids are equal opportunity pests and will attack a hemlock in exposed conditions or in long established and sheltered groves. For instance in the Blue Hills Reservation in Milton, MA there is heavy infestation with many trees on their last legs. Some of the hemlocks have been growing sheltered by woods disturbed only by fire events if at all over the last 100 years or so. If large tracts of old-growth protect by isolation from wind carried HWA or by limiting movement of certain species of birds then I'd speculate that it would slow the advance of HWA but not stop it. In my area hemlocks that have grown up isolated in yards away from the woods are acquiring HWA much later (3-5 years) then the woodland groves. I think that once HWA gets into contiguous woods it moves much faster. Andrew Joslin Jamaica Plain, MA Re: Hemlock and Adelgid Survey   orw-@fas.harvard.edu   Jan 23, 2007 06:49 PST  Hello Ed, as a researcher who has spent almost 12 years devoted to research on HWA, I am curious what the main purpose of the survey is. You mention that you want to find specific site information. Would this then be compiled to see if there were any landscape correlates with HWA infestation? The problem with many organizations is that they do not always know exactly when HWA entered an area. Richard Schulhof, the deputy director of the Arnold Arboretum, has investigated the response of HWA and the management implications for a variety of public agencies for his Masters thesis with me, so you may want to discuss that with him, as he'd be a good source of information. In our work we have detailed site information from 240 stands in southern New England including basal area, density, slope aspect, elevation, understory veg. etc. and even things like soil C:N ratio. Our experience has been once HWA gets firmly established, it will eventually lead to decline and mortality of hemlock regardless of site conditions. conditions are important in shaping the speed of the decline, with ridgetops and more exposed slopes experiencing more rapid hemlock declines. I hope this helps. Take care DAVE ORWIG RE: Hemlock and Adelgid Survey   Edward Frank   Jan 23, 2007 07:47 PST  Dave, Some of the reasons for the survey in my mind was to see what individual park managers actually knew about the hemlocks on their properties, did they know about the HWA, were there any plans in place to do anything prior to the adelgid getting there, and what were they doing about it once it was there. For some of them, they were procrastinating about even thinking about the issue, I hoped the survey would prod them into at least thinking about the problem. Personally I would like to see significant groves chemically treated to prevent their death as a holding method at least until we can see if any of the biological controls are effective. Much of the general information is available elsewhere on the spread of the adelgid, but I do find that most of the research I have read naturally deals with what the researchers themselves have found at specific sites. The detail is excellent, but... I keep coming back to the question of what, if anything, people who have worked out in the field at all these many locations, sometimes for decades, prior to the arrival of the adelgid may have observed that was not noticed by academic researchers. I am also aware of the potential misconceptions these people may incorporate into their observations. When I worked for the Bureau of Mining, at public meetings people seemed to think because they had lived somewhere for a long time they "knew" what was happening underground. But still I think it is worthwhile to give them a chance to express their observations. Ed Frank RE: Hemlock and Adelgid Survey   Edward Frank   Jan 23, 2007 08:06 PST  ENTS, Actually I found that a number of managers that replied were looking for guidance of what to do for certain trees or groves. Others were just beginning to look at the problem. Ed Re: Hemlock and Adelgid Survey   Jess Riddle   Feb 02, 2007 16:26 PST  John, I can certainly see how human alteration and large scale stresses on forests would make trees more susceptible to introduced insects, but I am confident that that degradation is not the dominant factor with hemlock woolly adelgid damage. Decline of hemlocks is closely correlated with both when the adelgid arrives and adelgid populations regardless of whether the tree is in an urban setting, an old-growth forest or somewhere in between. In the areas I am familiar with, the adelgid spread more quickly through large old-growth tracts than through an urban environment with a relatively hot and dry climate, presumably due to more continuous hemlock canopy in the former. Adelgid kills hemlocks in eastern North America because the trees have no natural resistance and naturally occurring predation on the adelgid is trivia. All other factors are insignificant by comparison. Jess   Home