Emerald Ash Borer Quarantine in Maryland
The emerald ash borer (EAB) is an exotic pest from Asia that infests and kills ash trees. Ash trees are a valuable resource that provides wood for baseball bats, cabinets, hardwood flooring, and many other commodities. In 2012, emerald ash borer were found in Montgomery County.
Since 2011, all of Marylandís counties west of the Susquehanna River and the Chesapeake Bay are under a quarantine to prohibit the movement of ash trees and wood out of the quarantined area, as well as movement of all hardwood firewood. This means that you cannot take the following out of these counties: the emerald ash borer; firewood of all hardwood (non-coniferous) species, including any piece thereof; nursery stock, green lumber, and other material living, dead, cut, or fallen, (e.g. logs, stumps, roots, branches) of the genus Fraxinus, including any piece thereof; or uncomposted ash chips and uncomposted ash bark chips larger than 1 inch in diameter in two dimensions.
The Maryland Department of Agriculture provides information about EAB and the quarantine. The information includes how to identify EAB and ash trees. If you suspect that you have an infected tree, the University of Maryland Extension Service is accepting reports of infected trees.
The Maryland Department of Agriculture placed much of Maryland under quarantine because EAB have now been found in five Maryland counties. It was first found in Prince Georgeís County after infested ash nursery stock as illegally shipped into the state in 2003. It was detected through survey in Charles County in 2008. In 2011 it has been confirmed in Allegany, Anne Arundel, and Howard counties.
Gypsy Moth Suppression Program in Cooperation with MDA
In the past several years, gypsy moth populations have been very low in Montgomery County. No spraying or other treatments are necessary to suppress gypsy moths. Field surveys, or counts of egg masses tell us that the numbers of gypsy moths are low enough that little damage to trees is expected. Will we see some caterpillars? Yes, but not so many that the trees will suffer long-term damage.
If your tree has been defoliated in recent years, be sure to water the tree through the hot summer months, and if you can, give it a deep-root fertilization treatment. If your tree has more than 50 percent of its leaves eaten by gypsy moths this year, please contact us(or call 311).
The Maryland Department of Agriculture Gypsy Moth Program has more information. Call them at 410-841-5922 for more information, or to report a defoliation.
Gypsy Moths vs. Eastern Tent Caterpillars
The two caterpillars are often confused. This factsheet explains the differences between gypsy moths and eastern tent caterpillars. (PDF, 1 pg, 27K) Eastern tent caterpillars are native and are much less serious than gypsy moths. The Maryland Department of Agriculture (MDA) recommends tearing apart the tents with a stick or a pole. This allows birds to feed on the caterpillars. Read MDA's overview of eastern tent caterpillars including how to control them.
Eastern Tent Caterpilllar
What Homeowners Can Do about Gypsy Moths
In the fall and winter, watch for gypsy moth egg masses in the crevices of tree trunks, fencing, and woodpiles. Remove the egg masses by scraping them into a zip-top plastic bag containing some water and detergent to kill the eggs. Then put the bag in the trash.
Be careful when removing egg masses because the hairs on the mass can cause topical allergic reactions.
Useful links for homeowners:
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