ported since 1992. It is intriguing that this location also 

 marks the northernmost limit of red pine scale and red pine 

 adelgid spread. 



HWA impacts on eastern and Carolina hemlocks vary 

 greatly. One extreme example is the complete mortality of 

 dominant hemlocks at Sparta Glen in northwestern New 

 jersey. At the opposite end of the spectrum are hemlock 

 stands in Pennsylvania that appear vigorous despite HWA 

 presence — in some cases for as long as 20 years. Most 

 states observe impacts between these two extremes 

 with infested trees exhibiting poor crowns and sharply 

 reduced terminal branch growth. 



Many states report that trees stressed by other factors of- 

 ten show the greatest damage from HWA attack. These pre- 

 disposing stressors range from poor site conditions, drought, 

 and elongate hemlock scale to defoliators like hemlock 

 looper and gypsy moth. Hemlock is shallow-rooted and 

 drought kills many fine roots near the surface. This year's 

 drought may increase tree mortality in the next few years, 

 particularly in areas already weakened by HWA. 



Tree mortality is reported in 1995 from Virginia, New 

 Jersey, New York, and Connecticut. In fact, mortality is in- 

 creasing. For example, the New Jersey Department of Ag- 

 riculture established permanent plots in 1988 to monitor 

 impacts. Since 1992 they have monitored tree mortality 

 in the I I hemlock stands that contain the permanent 

 plots Tree mortality increased sharply between 1994 and 

 1995 in the stands with the oldest infestations 



Based on the history of HWA in the East, we believe 

 three questions are critically important to answer before 

 we can effectively manage hemlock and HWA: How far 

 will HWA spread; how many hemlocks will die and, most 

 importantly, where; and how can we best protect hemlock 

 in our vulnerable forests and ornamental landscapes? 



Dennis Soto is an entomologist and Tom Luther, a geographic 

 information specialist, with the USDA Forest Service in Durham, 

 New Hampshire. For further information, call 603-868-7709. 

 EDITOR'S NOTE: The hemlock woolly adelgid, Adelgis tsugae, is 

 an aphid-like insect, probably from Asia, that was accidentally 

 introduced into the United States in 1924. It was first seen in 

 Oregon The presence of HWA can be identified by the white 

 cottony egg masses that are lined up along the twigs at the base 

 of the needles. The HWA is unusual in that it is very active during 

 cold periods of the year and relatively inactive in the summer. 

 Therefore, the best time to find new egg masses is in ]anuary and 

 February. The preferred treatment is a dormant oil spray, the key 

 to control is coverage of the entire tree.) 



TIPS FROM THE GRIFFIN GURU 



|Bctners (Bavben Center ^nc. 



656 South Mammoth Road (Rte. 28A) 



Manchester, NH 03109-5049 

 (603) 625-8298 • Fax (603) 622-4073 



Nursery • Greenhouses 

 Craft & Christmas Shop 



We Support The Plantsman 



Cheaper 

 By the Dozen 



We are just a bit surprised by the number of 

 orders going through these days in which the 

 amount that is ordered is just below the amount of 

 the next price break, 



An example of this would be an order for ten 

 Sharpie pens. By ordering a box of twelve (the way 

 they come from the factory), the savings would 

 be equivalent to paying for eleven and getting the 

 twelfth almost free. 



Lots of suppliers are willing to pass along a sav- 

 ings (discount) of 5 or 10% just to keep from break- 

 ing open the case and spending the time counting 

 out a lesser amount. 



Always be sure to check the quantity or price 

 break column for the best buy. 



One exception should be noted however. This 

 is for dated or dangerous products such as pesti- 

 cides. The cost of proper storage or disposal of un- 

 used pesticides can easily outweigh any savings 

 gained by overstocking. 



CaUus 



for your 



young 



plant/cutting 



needs. 



PS. COLE 



GrowerslaH 



251 North VUlage Road, Loudon, NH 03301 

 Phone 603-783-9561 Fax 603-783-9562 



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