Opposite pinnate leaves on an ash tree
Did that tree in the park have some odd marks on it? Were there some strange
holes in the shape of a D? Did the foliage on top seem a little thin? If it’s an ash tree,
that could be signs of the emerald ash borer.
The last article focused on the threat of the emerald ash borer and the ways
municipalities and agencies were combatting the spread. However, that is only part of
the solution. It is equally important for individuals to be able to identify both ash trees
and signs of infestation, especially if the have trees on their property or near where they
live and that will be the focus of this article.
The first part is knowing what ash trees look like and how to check for damage.
Ash trees are the genus Fraxinus and in the same family as olive trees. Ash leaves are
narrow and subdivided into smaller leaflets growing opposite each other. This type of
leaf is called opposite pinnate. Branches also grow opposite each other and the bark is
diamond shaped. Ash trees are found throughout the United States with the green ash
being the most widespread. Other types include the white, berlandier, Carolina, black,
pumpkin, blue, and Texas. The ash borer infests all species of ash.
Ash trees also have strong wood and straight grain and have been used for baseball bats,
tool handles, oars, and solid body electric guitars.
As was discussed in the previous article, the larvae chew serpentine gallereies in
the trunk and the adults make a D-shaped exit hole in the spring. These are two signs to
look for when checking ash trees. Other indications of infestion include bark splits and
branching in the lower part of the trunk, called epicormic sprouts. While the adults
don’t cause significant defoliation, they do eat the leaves and thinning in the canopy can
be another sign of infestation.
However, preventing the spread is equally as important as recognizing signs of
infestation. On its own, the emerald ash borer can travel about 10-15 miles per year,
but moving firewood can speed this up. Many states have put firewood quarantines in
place as a result. States with quarantine laws include Alabama, Arkansas, Colorado,
Connecticut Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maryland,
Massachusetts, Michigan, Minnesota, Missouri, Nebraska, New Hampshire, New Jersey,
New York, Ohio, Oklahoma, Pennsyvania, Rhode Island, South Dakota, Tennesse,
Vermont, Virginia, Washinton D. C. West Virgina, and Wisconson. While quarantines
vary from state to state, in general, no wood, nursery stock, wood packing, branches,
logs or stumps can be moved without a permit. Moving these materials without a
permit often carries a heavy penalty. Individuals should contact their local forestry or
environmental agency before moving any firewood. While eradication is not considered
a realistic option at this point, taking preventative measures and recognizing infestation
can go a long way to keeping ash trees as part of the ecosystem.
The Nature Journal 