DED preferences and observations

[Whitespider]

DED appears to be making another run at my wood lot. I’m noticing several trees with the signs, and a few didn’t make it through the summer. In the past, going on the standing dead, the bug has seemed to prefer the mid-life American elm, those around the 10-20 inch diameter with an occasional Red Elm victim. Its different this time… the preferred target is the really large American Elm, those that have survived unscathed until now, and the Red Elms. The south end of my wood lot is more Red than American Elm, and many are looking sickly… a couple died this year.

Maybe it’s because there are few 10-20 inch trees alive… but what few there are seem untouched. The juvenile trees, those under 10 inches show no signs of the bug. I’m not sure what all this means… just an observation. Has the bug morphed, modified its preferences or just taking what’s left? Have the younger trees, those seeded since the introduction of DED, developed a higher tolerance/resistance to the bug? Whatever it means, it looks as though I’m gonna’ have some absolute monster standing dead in the next couple years… a couple well over 3 feet diameter. And now that the EAB has been found in northeast Iowa, and the ongoing problem with Oak Wilt attacking the Bur Oak, and DED making another run… kind’a sad… wonder what will be left for my grandchildren?

Anybody else noticing anything?

 

[Dalmatian90]

Elms are very few and far between here (most were wiped out in the 1960s).

Good write up here of the life cycle: How to Identify and Manage Dutch Elm Disease

You might have more aggressive beetles, or just more, or just bad luck.

Even with the isolated trees here and aggressive treatment of certain highly visible ones, sometimes they go for decades and then just get sick. I think it's that while the Elm Beetles are the best ones for spreading it, occasionally other beetles and spores will randomly combine to infect them.