Farm Progress

Beetle threatens sugar maples, syrup industry

Asian longhorned beetle leads to 308-square-mile quarantine in U.S.

Alan Harman

July 20, 2017

7 Min Read
CHINESE INVADER: The Asian longhorned beetle was believed to be transported here in untreated wooden packing crates from China.

Maple syrup producer Ron Kistler sees Armageddon threatening his 122-year-old family business — and it’s not the global warming impact that he’s already experiencing.

The danger is from the Asian longhorned beetle, a Chinese invader that since 1996 has caused tens of thousands of trees to be lost in the United States and Canada. At stake is not only the $2.5 million earned by the maple syrup industry, but also the $3.7 billion spent by tourists traveling to see the fall colors, dominated by maple trees.

The beetle feeds on hardwood trees, eventually killing them. The worst-case scenario could see the beetle destroy all the North American sugar maples.

U.S. quarantine
Currently, 308 square miles are under quarantine in the U.S. This includes:
• 137 square miles in New York, covering the New York City boroughs of Brooklyn and Queens, and a portion of central Long Island

• 110 square miles in Worcester County, Mass., which includes the cities of Worcester, West Boylston, Boylston and Shrewsbury, and a portion of the towns of Holden and Auburn

• 61 square miles in Clermont County, Ohio, including East Fork State Park, Tate Township, and portions of Monroe, Stonelick and Batavia townships

Infestations have been eradicated in Illinois in 2008, New Jersey in 2013, Boston in 2014, and for New York — Manhattan in 2013, Staten Island in 2013 and Islip in 2011. It also was found in the York Region of Ontario — part of the Greater Toronto area — in 2003. The Canadian Food Inspection Agency spent more than C$33 million (US$24.4 million) and then declared the beetle eradicated only to have it reappear four months later.

The Center for Invasive Species Research (CISR), based at the University of California Riverside, says the beetle (Anoplophora glabripennis) has been intercepted widely at warehouses and ports throughout the U.S. and is likely to continue its continental spread. The scenario is similar to American Dutch elm disease, caused by a fungus spread by elm bark beetles, which destroyed native populations of elms.

Demise of trees lengthy
The devastation of the maple and 12 other hardwood trees is not going to happen overnight; it could take decades and possibly centuries.

John Bedford, Pest Response Program specialist for the Michigan Department of Agriculture, says confirmation of the finding of a beetle would see teams of federal and state agencies swing into action at a moment’s notice to prevent such a catastrophe.

Ron-Kistler-Harman-0717H1-3055B_1.jpg
REAL THREAT: Maple syrup producer Ron Kistler produces maple syrup on the family farm just outside of Ludington in Michigan’s northwest region. He sees the Asian longhorned beetle as a real threat.

Thus far, there have been false alarms, but none of the beetles has been found in the state. As the beetle is a federally regulated pest, the initial response would be from the USDA, backed by state agencies, armed with everything from an area quarantine to the complete removal of the infected trees.“Early detection followed by a rapid response will be key to Michigan’s success in eradicating the beetle, should it ever be detected here,” Bedford says.

End of maple industry?
Kistler began working full time in 1978 on the family operation, just outside of Ludington in Michigan’s northwest. He sees the Asian longhorned beetle as a real threat. “If the beetle progresses through maple trees the way the disease went through elm trees and the ash trees — you hate to think about it — but it may be the end of the maple industry.”

Industry authority Timothy Perkins, research professor and director of the University of Vermont Proctor Maple Research Center, says there’s certainly that potential. But he says the total destruction of the sugar tree estate would take a reasonably long time. “It’s not a fast-spreading insect,” Perkins says.

CISR says the longhorned beetle, widely distributed in China, Japan and South Korea, appears to have reached the U.S. in untreated wooden packing crates from China.

Bug up close
The beetle’s off-white pupae are about an inch long, and the eighth segment of the abdomen has a protruding structure. The adults, jet black with white specks, are about an inch long, with 11-segment antennae. They can overwinter as an egg, as larva developed within an egg, as a larva, or as a pupa.

Cavities chewed out by females are found in tree trunk bark and branch junctions, or on the trunk itself. As larvae mature, they enter the heartwood of the tree, destroying the quality of the wood and eventually killing the tree.

Adult beetles emerge in the summer through three-eighth-inch holes in the bark. Sap flows heavily from these large wounds, and infested trees are prone to secondary attack by other diseases and insects. Clues to the beetles’ arrival include maples with dying branches and the exit holes.

Methods to fight the pest are limited. “In Massachusetts, when they found the beetle in a guy’s sugar bush, they cut down all his trees and anything within 4 or 5 miles,” Kistler says. “That’s basically their only defense at this time,” he says. “It could be a disaster.” Kistler says systemic pesticides have been used on other trees the beetle has targeted — ash, birch, elm, golden raintree, hackberry, horse chestnut, katsura, London planetree, mimosa, mountain ash, poplar and willow.

Systemic pesticides, Bedford says, have been used on all tree species, including maples, but their use is not a method of eradication. “The pesticides are a suppression method,” he says. “Pesticides may work as suppression method on all maples. It just may not be desirable as it relates to the use of sugar maples that are to be used for syrup production.”

Kistler agrees. But this won’t work for sugar maples. “If you use a systemic insecticide, obviously you can’t harvest the sap,” he says. “We are trying to make food out of the sap, so that wouldn’t be a possibility. You don’t know if you could convince customers that it would ever be safe to eat. I don’t think you could treat the trees that way if you wanted to stay in business. If the beetle goes right through the maple belt, there would be no syrup.”

Maples planted as a crop
Kistler says researchers are planning for life after such a disaster. “They are planting maple seedlings and letting them get to be about 4 or 5 years old, with trunk diameters of about 3 inches,” he says. “They cut them off about 5 feet high, put a bag over the top and put a high vacuum on them and suck all the sap out of the seedlings. They can make maple syrup out of that.

"The roots will still have enough energy that they will generate shoot growth and growers can cut it off a little bit lower the next year,” Kistler says. “I think they can get about three years out of that planting before the treatment kills the trees.”

He says the idea would be to plant maple seedlings like corn. “You would have 5 acres here and you would start another 5 acres a year later and another 5 acres a year after that,” Kistler says.

“This would produce a continual crop rotation. It would definitely supplement a woodlot, if you had any woodlots left. It’s a possibility, but an expensive proposition at that,” he says. “You would just hate to see these woodlots lost to something like a bug that came from overseas.”

Guard against pest
Here’s information on how to guard against the Asian longhorned beetle:

• Pay attention to trees, especially maples, with dying branches. Look for the characteristic exit holes in large branches or the trunks. Many websites have good ALB photos and information. If you see a suspect tree or beetle, take photos, record the location, try to collect suspect beetles in a jar and report it to Michigan Department of Agriculture and Rural Development by emailing [email protected] or calling the department’s Customer Service Center at 800-292-3939.

• If possible, take one or more photos of the invasive species being reporting. Also, make note of the location, date and time of the observation. This will aid in verification of the report. Provide your name and contact information if follow-up is needed.

• The Midwest Invasive Species Information Network (MISIN) online reporting tool is found at misin.msu.edu/report. You can also download the MISIN smartphone app and report from your phone.

• Do not bring firewood from out of state and do not move firewood around Michigan. If firewood is needed, buy local.

Harman writes from Brighton.

Subscribe to receive top agriculture news
Be informed daily with these free e-newsletters

You May Also Like