Oak Wilt Spreads Quickly, Imperils Trees
While bare, leafless trees are the norm during cold winter months, the state of East Hampton’s oak trees, which are subject to a spreading and untreatable fatal disease called oak wilt, remains to be seen until spring, when sampling and aerial examinations will be done.
Oak wilt, a fungus that blocks the flow of water and nutrients from the roots to the crown of the tree and causes leaves to wilt and drop off, has been found upstate and now across Long Island, from Brooklyn to areas in the towns of Babylon, Islip, Riverhead, and Southold. The disease has been killing thousands of oak trees in the eastern United States each year. Because it is unlikely to have spread from town to town without infecting trees along the way, it is expected that widespread disease will be found throughout Suffolk County, including in East Hampton. Infected trees will be cut down.
To try to contain the spread of the disease, the New York State Department of Environmental Conservation plans to issue an emergency order creating a “protective zone” encompassing the entire county. Under the order, moving oak wood — or firewood logs of any species, as it is difficult to determine whether cut logs are oak or not — out of the quarantined area will be forbidden.
The emergency order, similar to those already in effect for other locations, will prohibit the removal of “any living, dead, standing, cut, or fallen oak trees or any portion thereof, including branches, logs, stumps, or roots, and green oak lumber and firewood (of any species) out of the protective zones unless it has been chipped to less than one inch in two dimensions.” Transported wood can harbor the fungus or the beetles that can spread it, according to the D.E.C.
Beginning in the spring, when the oak wilt fungus is active, the D.E.C. will remove and destroy trees that have tested positive for the disease. Intensive sampling will take place across Suffolk as well as in Nassau and Kings Counties, and aerial surveys will be conducted in July, when the fungus is most apparent, to determine the extent of the disease.
All oaks are susceptible, but red oaks often die much faster than white oaks — within a few weeks to six months — and they spread the disease far more quickly. White oaks have a lower risk of spreading the disease, according to the D.E.C., and can take years to die.
Oak wilt was initially discovered in Wisconsin in 1944 and spread throughout the Midwest and Texas. A protective zone was established last year around areas of Islip where infected trees were found.
Below ground, the fungus spreads through tree roots, and above ground by beetles that feed on tree sap and bark. Beetles can spread oak wilt spores throughout an area of several miles.
Symptoms of oak wilt infection include a brown coloration that develops on leaves, starting at the outer edges and progressing inward. The leaves suddenly wilt, and, during spring and summer, may fall. Tree branches die back, starting at the top of the tree canopy and progressing downward, and mats of fungal spores may develop under the bark, which can raise and split it.
The D.E.C. has encouraged people to report possible instances of oak wilt to its forest health office, by phone at 866-640-0652 or by email to [email protected]. Photographs of the symptoms should be included.
Pruning or wounding oak trees should be avoided in spring and summer, when spore mats may be present and beetles are most active. The D.E.C. advises that if a wound occurs, it should be dressed immediately with latex paint to deter beetles from landing there.
The D.E.C. is also leading the fight against southern pine beetles, another spreading scourge to trees, in Long Island’s Central Pine Barrens. A total of $513,000 in grants will be awarded to Suffolk County agencies and towns working to address the problem, including the Town of Southampton.