Many U.S. states prohibit movement of firewood in some areas in the hope of slowing (or even stopping?) the spread of the emerald ash borer. Is this policy effective to a significant degree? I can’t help but suspect the borer will continue to spread, and wonder if slowing the spread really helps.
The same movement prohibitions exist here in Ontario. Despite that it has and continues to spread. I really don’t know what to think. We’ve all lost a lot of trees here over the last 10 years or so.
Quarantines could be effective, if they were 100% observed by people in the area. But that doesn’t happen. And the bugs do travel on their own, when they can find a source of delicious ash trees.
But they do seem to help, in terms of slowing the rate of infection. (Though it’s hard to tell. But it seems like places with quarantines seem to slow down the inevitable spread compared to places without them.) Also seems to help to have immediate removal of any tree identified as infected. And some cities are working on amputation – preemptive removal of all ash trees before the infection sets in.
Based on conversations with a friend on the Park Board.
They’ve actually done research on dispersal for obvious reasons. Most stay within about a 1 mile radius of their hatch site. About 20% travel 5-15 miles About 1% of mated females will travel in excess of 15 miles. So it’s reasonable to assume that even with quarantine, you would expect at least a 15 mile expansion every year. We first spotted Emerald Ash Borer in Detroit in 2002. Under perfect quarantine, it is reasonable to assume that they would be right now within a 250 mile radius of Detroit (This isn’t strictly true since it is likely that they were already established prior to their discovery in Detroit, but for a thought exercise.) So under complete quarantine we would expect them to be roughly stretching from Toronto to Chicago and as far south as southern Ohio. Their actual range is Nebraska to Boston and as far south as Louisiana, so quarantine would definitely have been effective. Under perfect quarantine, they would probably be 50 years away from Louisiana and we might have enough time to come up with control methods. As is, we’re pretty much screwed. Ash trees except blue ash are basically going to be extinct or close to it within the next decade or so.
is there any thought or prediction on what happens when the ash trees are too few and far between to support the feeding habits of the Ash Borer?
Am I naive enough to think once the ash trees have virtually (but not entirely) disappeared, the Ash Borer population will starve itself out? Then would re-population of Ash trees be feasible?
I’m confident that ash trees will not be completely wiped out, but I wonder if Ash Borers will be able to ‘jump species’ and feed on other trees to maintain an extant population able to pounce on a lone ash sapling, or if they will die off.
For those areas around Detroit, are there ANY ash trees at all, and if not, are there ANY ash borers?
They are still there, primarily attacking saplings. The big fear is that they are adapting and moving to other species. They have made the jump to White Fringetrees already and close genetic variants of EABs feed on black walnut and elm, but this variant doesn’t seem to.
Also, while black and green ash pretty much all die, blue ash in Kentucky and Tennessee has about a 40% survival rate and white ash has about a 20% survival rate, so there are still remnant ash that will incubate EABs after an infestation.