What Is The Hemlock Woolly Adelgid?

The Hemlock Woolly Adelgid is an aphid like insect that breeds over the winters in a cottony sac on the needles of hemlock trees.   This destructive insect feeds on the nitrogen in the Hemlock for which it resides and can overwhelm and infest your hemlocks in just one season.  The effects of this infestation result in needles of the hemlock to turn a greyish-green as they drop off the hemlock and eventually the hemlock dying if left untreated.

The insect easily migrates throughout neighborhoods by wind, squirrels, deer and birds due to it’s “sticky” nature. The Woolly Adelgid nests and reproduces within the crook of hemlock needles, twigs and branches.  These destructive tree insects are hardly detectable at first sight, however over time as it begins reproducing; it creates a cottony-like substance easily seen in tree joints.  While sucking sap from the hemlock as they are feeding and leaving behind toxic saliva onto the tree, they cause the needles on infested hemlocks to turn a grayish-green color, and then drop from the tree usually within months. Any new sprouts are also damaged, so little to no new growth on the tree is ever realized. In most cases, hemlocks are often severely damaged quite quickly and become ugly with little to no chance to recover and killed within a few years of becoming infested.  
If you notice that your hemlocks are beginning to have a grayish-green appearance with needles dropping and bare areas showing up within the interior of the branches, this could mean that the Hemlocks are infested.  Homeowners should note to never fertilize their hemlocks or surrounding area if they are infested with Woolly Adelgid. Fertilizers contain nitrogen and by doing so you are in effect, feeding the pest and increasing their population.


Treatment of the Hemlock Woolly Adelgid

At North Eastern Tree Care, we offer several solutions to this destructive insect.
Hemlock Woolly Adelgid can damage trees very quickly!  Horticultural (Dormant) Oil and Insecticidal Soap applications applied by North Eastern Tree Care safely coat the insect and effectively suffocate the pest.

Be advised that as a homeowner, you should only use a qualified and accredited tree care service such as North Eastern Tree Care for these applications.  We offer the proper equipment to get the smallest droplet size onto the hemlock to coat the insect and trees without the product "rolling off" the target pest. Landscape companies and other tree care companies may not have such sophisticated equipment resulting in poor coverage of the infested tree, a waste of money and your hemlocks dying.  Products bought at garden centers are similar products, but are completely ineffective without the proper equipment, training and sticking agents added to the service.

Systemic Tree Injections and Systemic Soil Applications are highly effective applications used alone or in conjunction with Dormant Oils and/or Insecticidal Soaps. By injecting or soaking the root system with a systemic product, a Licensed Arborist from North Eastern Tree Care will eliminate 95% of the Woolly adelgid for up a minimum of one year with one application. By systematically treating the hemlock, any wooly adelgids that feed on the tree will be affected.


Hemlock Woolly Adelgid Services



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