|Asian longhorned beetle exit holes are about the size of the |
diameter of a pencil.
There are exceptions. For example, the invasive tunicate in Winchester Bay was reported by an alert volunteer diver working for the Oregon Aquarium. German yellowjackets in Tillamook were discovered by a resident. And Patterson’s Curse in Linn County was recognized by a visitor from Down Under.
Earlier this month, a resident in Bethel, Ohio reported to a state forester unusual damage on maple trees. It turns out the damage was caused by the Asian Longhorned Beetle (ALB), one of the worst invasive species threats to hardwood trees in North America. This is the latest in a string of ALB infestations discovered by citizens in the United States. Unfortunately, the infestations exist for 5–10 years before anyone notices a problem.
There are two good reasons why ALB gets reported by the public:
1) it is big and weird-looking; and
2) there are no good survey methods.
We have some big native longhorned beetles that resemble ALB, but they are not likely to show up in your yard. ALB, on the other hand, feeds on and eventually kills maple, willow, horsechestnut, elm, and other common yard and street trees. Reliable surveys for ALB require tree climbers. From the ground, the best that can be done is to scan the trunks of susceptible trees looking for half-inch diameter exit holes. In the past, Oregon survey crews did this, but looking for a needle in a haystack would likely be more productive.
Clearly, we need more trained people looking for ALB. We think a better strategy is to train master gardeners, arborists, and other people that are on the front lines to keep their eyes open. The same could be said for dozens of other invasive species on Oregon’s 100 Most Dangerous Invaders List http://www.oregon.gov/OISC/most_dangerous.shtml. Each year there are surveys for only a small fraction of these species.
What can we do? The reality is we need both a robust survey program and an educated citizenry.
Targeted surveys are often critical to successful early detection and rapid response (EDRR) programs. They can be very efficient, especially if effective traps are available. Gypsy moth traps, for example, can attract moths from a quarter of a mile away! Efficient traps are a big reason why we’ve been able to keep the gypsy moth from establishing itself in Oregon, despite repeated introductions during the last 30 years.
When an invasive species isn’t detected early, eradication is often impossible or hugely expensive. The folks that live near Bethel, Ohio are about to find that out. If this ALB infestation is as big and well entrenched as the others that were finally noticed by citizens, millions of dollars will be spent on eradication, and thousands of trees will be destroyed. Check out the video called Lurking in the Trees for a scary look at what happened when ALB was found in Massachusetts (the Oregon Department of Agriculture has copies available for lending).
Recognizing that government can only do so much and budgets aren’t keeping up with the introduction of new invasives, we’ve got to get smarter about our defenses. I don’t think private industry is the only answer—there is no profit to be made from invasive species EDRR, and even well-trained arborists can’t cover Oregon’s geography. What we need is lots of people sufficiently well informed to recognize new weeds and potential pests. Then we need them to report their findings so that the species can be identified and the appropriate responses taken. Digital pictures, many taken with cell phones, are becoming an important tool for transmitting pictures of suspicious weeds, bugs, and snails. Even if the quality isn’t the best, an expert is usually able to determine if further followup is warranted. In Oregon, we’ve made it easy for people to report new sightings with our telephone and online hotlines: 1-866-INVADER or http://oregoninvasiveshotline.org/.
If we work together, maybe we can avoid what just happened in Bethel, Ohio. ALB would be very destructive to Oregon; we don’t want it here. Because there is neither an effective trap nor survey, it is up to all of us to remain vigilant. Keep your eyes open, and report it if you see any big weird beetles, pinky finger-sized exit holes in tree trunks, or anything else that doesn’t look like it would be good for Oregon. Collective vigilance is our only hope.