Hemlock Woolly Adelgid: The end for Hemlock Trees?

The Eastern Hemlock tree is very important to our earth and the streams and wildlife in this environment. The importance of the Hemlock is its source of food and shelter to several species of birds and wildlife. The Hemlock's thick foliage protects streams as well by filtering in sunlight. Without the hemlock's dense leaves/vegetation filtering sunlight into streams, the water temperature in these streams would increase- which would decrease the oxygen levels in the water, ultimately affecting aquatic life and fish in these streams negatively. As well as helping critters in their ecosystems in the environment, the Hemlock is a very unique and versatile tree species for landscape uses and there is no substitute for it. The hemlock forests are unusually dark ecosystems, and the hemlock trees cast a dark shade for these ecosystems. As the hemlocks are dying off, so is the forest canopy, the plants and wildlife that once lived below cannot live normally. Hemlocks are also important in the control of erosion. These large confiers stabilize and hold the soil on steep slopes, streambanks, and lakeshores. The Hemlocks are also the most important conifer that house deer through the winter months. The needles are very tiny yet dense which creates something that holds snow and serves as a "roof" that creates a "microclimate of warmer temperature below the forest canopy." Overall it helps deer to move quickly and freely without expending too much energy to find food. As you can see, hemlocks provide a multitude of envrionmental benefits.

The Hemlock Woolly Adelgid is a beetle originating from Japan, it was first introduced in the 1920s to the Pacific Northwest and in the 1950s to Washington, DC and Richmond, VA. The woolly adelgid beetle feeds on hemlock needles of hemlock trees. This deprives the trees of nutrients and if it is not treated, the hemlock will die within five to seven years of the first infestation. This beetle is very small but may be recognized by a dry, white woolly substance left on the twigs of the branches. This "wool-like" substance is usually most conspicuous in the spring because this is when egg masses are present. The way in which the adelgid hurts the eastern and Carolina hemlock is by sucking it's sap and injecting a toxic salive while feeding. The needles of a hemlock that have been infected turn a grayish-green color and then drop off of the tree. There is barely any new growth and the hemlock ends up looking like a 'tree-skeleton'. The major limbs of the tree die within two years and this begins at the bottom of the hemlock then works its way up (even if the infestation is evenly distributed).
The hemlock woolly adelgid has already killed thousands of hemlocks and there needs to be more action taken to manage the growing populations of te woolly adelgid. The initial decision on whether or not to use chemical control measures should consider the value of the trees relative to the anticipated cost of protecting them over the long term. Pesticides seem to be the most effective way of managing the woolly adeldigs, and it might be a good idea to identify groups of trees or single trees that have a significance to their property of location and maybe concentrating chemical resources are gone the efforts on these spots. This may be more effective than trying to save all the hemlocks at once. I support the use of pesticides in saving the hemlocks due to previous research proving this to work best. This research has shown that injecting adelgid-killing chemical into tree boles or into the soil may kill them and even prevent new infestations for over a year. A chemical suppression program has been established that control is restricted to large, high value trees. Although this may be costly, and temporary. I support it and think it is a good idea to stop the woolly adelgid from completley wiping out Hemlocks, and gives resrearchers more time in figuring out a more permanent way to deal with this envrionmental problem.