Oak Wilt Found On Long Island

Residents Encouraged to Report Any Sudden Loses of Oak Tree Leaves during the Month of August

New York State's Department of Environmental Conservation (DEC) and Department of Agriculture and Markets (DAM) today announced that the oak tree disease, oak wilt, has been detected in the Central Islip area of the town of Islip, Suffolk County. The disease was identified by the Cornell Plant Disease Diagnostic Clinic after samples from a symptomatic oak tree were submitted by a concerned tree care professional.

This is the second location in New York that oak wilt has been confirmed, the first being in Schenectady County in 2008 and 2013. After the provided oak samples tested positive for the fungus that causes the disease, the tree care professional removed and destroyed four trees that exhibited signs of being infected. There is no known treatment to contain and kill the oak wilt fungus other than to remove the infected trees as well as any surrounding host oak trees.

"The infestation is small and isolated making an aggressive eradication response warranted and feasible to address this serious disease." said DEC Commissioner Basil Seggos. "Additional oak trees will need to be removed in the immediate infected area to stop oak wilt in its tracks."

DEC will utilize the eradication protocols from the Schenectady County occurrence to control the Islip infestation. An emergency order has been issued establishing a protective zone that prohibits the removal of any living, dead, standing, cut or fallen oak trees or any portion thereof, including branches, logs, stumps or roots, green oak lumber and firewood (of any species) out of the immediate area unless it has been chipped to less than one inch in two dimensions. The order also creates a 150 foot "red oak free zone" around the specific location where the infected trees were discovered. All red oak located in these zones will be removed by DEC and destroyed in order to protect the remaining oak trees in the area.

State Agriculture Commissioner Richard A. Ball said, "Acting now, while the incident is isolated, is a critical step toward preventing the spread of oak wilt and saving our trees. This aggressive plan will protect additional trees from infection and help eradicate the infestation quickly."

Impacted property owners will be contacted to inform them about oak wilt and provide information about how to help protect their remaining oak trees. DEC will schedule a public meeting to address questions and concerns regarding the planned activities to eradicate the disease. Aerial surveys, as well as ground surveys, will be conducted through the coming weeks to determine the number of trees that need to be removed from the red oak free zone and tree removal is expected to take place within the next six months. Additional oak samples are being collected from surrounding areas to determine if further action is necessary to control the spread.

Oak wilt is a very serious tree disease in the eastern United States, killing thousands of oaks each year in forests, woodlots and home landscapes. It is caused by a fungus, Ceratocystis fagacearum. The fungus grows in the water conducting vessels of host trees causing the vessels to produce gummy plugs that prevent water transport. As water movement within the tree is slowed, the leaves wilt and drop off, and eventually the tree dies.

Members of the public are encouraged to report any occurrences where an oak tree suddenly loses its leaves during the month of August to the Forest Health Information Line toll-free at 1-866-640-0652. For more information about oak wilt or the emergency order, visit DEC's website.