The Emerald Ash Borer is an actual parasite of ash trees, that can cause extensive damage. Now, it is gaining territory in the US.
The Emerald Ash Borer is a beautiful small emerald green insect, only a few millimeters long. However, it can prove deadly to ash trees, in sufficient numbers, because it prevents the three from getting its nutrients.
The adult Ash Borer does not actively cause serious of damage to the tree, as it only feeds on its leaves. Its larvae however can provoke quite serious effects. The adult female lays its eggs on the surface of the tree bark, in a crevasse. Shortly, the larvae can spring out of the eggs and start chewing their way through the bark. They settle in the space between the tree bark and the wood, where the tree’s nutrient vessels are located.
The larvae feed on these nutrients and begin growing in size, and then start moving around under the bark in search of more nutrients. The larvae can grow in size quite a bit, as their body is segmented. This is the moment when it starts damaging the tree, because the more it moves, the more vessels it affects and the more nutrients it consumes.
When the larvae are ready, they move towards the next evolutionary stage, which is the pupae. When the pupae are sufficiently evolved, they become Emerald Ash Borer adults, that simply find a hole in the bark and fly out of the tree, in search for their mates, usually during springtime.
Is is believed that the Emerald Ash Borer has come to North America along with a firewood transport from Asia, where the insect is widely spread. The trees have evolved sufficiently to live with the infestation there, but in the US, the trees were naive to the infection, therefore defenseless.
The Emerald Ash Borer cannot fly too far on its own, so the infestation does not spread too far without human implication. The most important means of transmission is through the transportation of firewood from an infested area to a naive area.
Along the time, the Emerald Ash Borer issue has become so serious that there is a quarantined area that includes the states that are fighting this particular bug infestation. Therefore, it is actually illegal to move wood from these states. Only recently it has been authorized to conduct interstate shipment inside the quarantined area.
The states that are included on the quarantine list are Connecticut, Ohio, Missouri, Indiana, West Virginia, Pennsylvania, Illinois, Massachusetts, Virginia, Michigan, Iowa, New York and New Jersey and also some parts of Tennessee, Georgia, Wisconsin, Minnesota, Arkansas, North Carolina and Maryland.
Recently, the Maryland Department of Agriculture has identified the emerald tree-killing beetle in four new counties. Its presence has been confirmed in Queen Anne’s, Dorchester, Harford and Baltimore, that have now been included on the quarantine list.
When an ash tree becomes infested, the symptoms that can be observed include canopy thinning and the decrease of leaf presence. As a diagnostic method, the characteristic D-shaped holes that the adults use to exit the tree need to be identified. Furthermore, if part of the tree bark is pulled out, the galleries that the larvae form can be identified and this is also characteristic for the Emerald Ash Borer.
As a treatment for infested trees, there is a special insecticide that can be used. It is called TREE-äge and it comes in the form of stem injections. These are applied through holes that are drilled into the tree bark just deep enough to penetrate the tree bark only and not the wood.
Then, a special applicator is used to inset the insecticide. The chemical substance will then pass into the tree’s nutrient vessels and it can kill all the larvae that are present inside the tree. Furthermore, it is actually potent enough to kill the adult borers who are feeding on the leaves as well.
This type of insecticide must be applied by a specialist, as it is not available to the general public. There are several methods out there that everyone can utilize, such as insecticides that are sprayed on the tree bark or on the ground. These types of treatment need to be applied periodically, so that they may be effective.
It is of the utmost importance that these emerald-green insects are not transported from one state to another, under any circumstance. Therefore, American citizens need to be aware of the danger that this tree parasite poses to ash trees everywhere.
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