Hemlock and ash trees are in danger

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Hemlock and ash trees are in danger TRI-COUNTY AREA—Invaders are arriving daily in the area and their target for destruction is Hemlock and Ash trees; all of them. Hemlock are one of the most attractive and abundant conifers in the region and they are already showing evidence of the presence of Hemlock Woolly Adelgid. The serious non-native pest is so tiny they are almost invisible from a few feet away, although a trained eye can detect them from a short distance. In addition to the woolly adelgid, emerald ash borer and Asian long-horned beetles are also a great concern. All three are present in New York State and trees die when infested by any of the three. On March 24, Cornell University Cooperative Extension Associate, Forest Health Specialist Mark Whitmore, presented a training seminar on detection of these damaging insects for volunteers who will to assist property owners in determining the presence of the pests. There is great concern because if any of them occur in a large scale, tree mortality could have extensive ecologic, economic and social consequences. Whitmore said, “Bugs are mucking everything up. The thing about the bugs is they can take out a whole tree. They have the potential to wipe out species. Any of the three insects can kill trees within just a few years after infesting a tree, often selecting older trees as easy targets. After the eggs hatch, they search for feeding sites on the twigs at the base of hemlock needles. They feed on the young twig tissue, remaining there throughout the balance of their development. The hemlock woolly adelgid feeds on stored starches which are critical to the tree’s growth and long term survival.” A large beautiful hemlock viewed as part of the seminar was virtually covered with the white woolly material that gives the adelgid its name. Positive identification is important because spider sacs and spittle bugs can also produce white spots on branches that are similar. Control is a huge challenge. The woolly adelgid has no natural enemies in the eastern United States, no resistance by hemlock hosts, they are difficult to detect at low population levels and there is no area-wide treatment available. There are environmental, biological and chemical controls and Whitmore discussed them one by one. Biological control can’t happen overnight and chemical controls are not an economical area-wide treatment. Systemic treatments are less damaging than foliar sprays. The woolly adelgid is a tiny insect, less than 1/16 of an inch long. It becomes easier to detect after it produces a covering that has the appearance of white wool called ovisacs that protects both the woolly adelgid and its eggs. The material protects eggs from natural enemies and prevents them from drying out. It can be easily seen from late fall to early summer on the outermost branch tips. Woolly adelgids are dispersed as a result of wind as well as birds and forest dwelling animals that come in contact with the sticky ovisacs. Most long distance movement is a result of humans transporting infested nursery stock. The emerald ash borer is a strikingly beautiful metallic green insect. Tiny, it can fly and attacks all ashes and can kill them all. This is particularly a concern here because New York State has the heaviest concentration of ash in North America. The emerald ash borer was discovered in Randolph in the western part of New York State last year. The larvae damage the vascular system of the tree as they feed. Whitmore called the spread of the borer “a people problem.” One of the ways it is spreading is movement of firewood from place to place. He said, “Firewood can’t be moved. This must become part of our culture.” Firewood is often available near camping areas throughout the state and purchase of local firewood should be the choice of campers. New York State is one of the few states with regulations on moving firewood. The last bug discussed was the Asian longhorn beetle, termed by Whitmore as, “The scariest bug in the woods.” There are several reasons for this label including there is no natural resistance to it and the difficulty in detecting it. He said this beetle could cause the loss of a good portion of maples. Control of any of the three is difficult. Whitmore cited state parks as one of the worst places in the Finger Lakes because of the lack of funding for control measures. Some parks have hired experts to assist and Whitmore hopes the U.S. Forest Service will be able to provide some funding for control. Research is continuing to find natural enemies of the insect. Loss of trees to invasive insects has broad ecological concerns from the soils to forest and stream temperatures and shelter for animals and migrating birds. Tree mortality also opens the land to invasive plant species that could prevent the growth of more useful species of trees and plants. In urban areas the loss of trees include changes in shade and home cooling costs and in property values. With the loss of shade trees, quality of life and sentimental value of the loss of favorite trees also result. During the course of the program, Whitmore said, “A tree is a genetic encyclopedia of everything that has gone right. It’s important to conserve what we have, especially old growth trees.” He said he is training master gardeners and others to be resources for the community.		$element(adman,groupads,YatesRight1)$ $element(adman,groupads,YatesRight8)$ $element(adman,groupads,YatesRight6)$

Hemlock and ash trees are in danger

Hemlock and ash trees are in danger

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