Not sure about root grubs, but flowering plum is a bad idea in general because it is a fruit tree that is susceptible to many pests and diseases. I would look into serviceberry, amelanchier arborea.

It could have been lilac borer, which I have had in one of my lilacs. Were the leaves smaller than usual?

yes, the leaves were much smaller than normal. I thought root grub because the only bugs were in the bottom cut; the rest of the bush was clean.

The wood was surprisingly dry to start with, 25%. I will dry it carefully though; thanks for the advice.

There a dozen large lilacs on the 2 miles I walk my dog. Only one other didn't come up normally; but yes, Western NY.

i have similar plants on my 5 acres.. in independent micro climates ... you cant compare yours to plants 2 miles away ...

i dont really know what a root grub is.. never heard of such a thing using those words, i mean... and frankly.. you only found a couple .. i bet the were japanese beetle grubs.. which would be irrelevant .. especially as to number ... i think you are stabbing in the dark ...

how old is this thing.. when planted.. is it established.. how about some pix ...

any pix of the grub???

and i have never heard of a 9 inch trunk on a lilac .... i love to see a pic of that ...

see link below for how to deal with purple plum ... extremely short lived tree .. lucky if you get 10 years out of it ...

sorry this sounds so cranky ... take it for the effort made.. rather than .. well.. you know ...

ken

http://forums2.gardenweb.com/discussions/1658852/how-to-properly-prune-a-purple-leaf-plum

Mine is cut down; that is how I found the grubs. But there are a few in the area about the same size; I will try to get a picture of those. The ones I know of are all by the street, so they should all be about the same microclimate. The street was originally build up about 1925, so they could be that old.

The town is planting the trees and have a choice of 5. The only two that don't get big are a crabapple and the plum. I have two crabapples already, so I though the plum would be nice. I am hoping to be out of NYS within 10 years, though my wife has other plans. Plus, its too late to change now.

Ken is right about the plum, crabapples would be the same. Why don't you invest some money in a quality tree instead of relying on municipal idiots. Never heard of root grubs either.

Yes yes, as we know, all people in municipalities are idiots. Excellent point, Logan Johnson. You've added so much here!

When we first moved here, we had a very large lilac in the backyard. It was *not* Syringa vulgaris, Those are in the front yard. It may have been a Korean lilac, but I don't remotely have the shrubby, non-caning lilacs straight. Whatever it was, it was about 10 ft tall, with a single trunk at least 8 inches across, and a scent more like privet than lilac. At some point in time, a fairly large side branch had been cut off the trunk leaving a stub. When I went to cut it down, I found a lot of rot around that cut. Even if I hadn't wanted rid of it because I hated where it was, it would not have lived much longer. The S. vulgaris in the front yard have been mowed, chain sawed, attacked by the town mower, and hit by a car, but have never had rot issues.

Tom, I wasn't saying all municipalities are idiots. I have helped the town do landscaping, planting lots of sugar maples and eastern red cedar.

Lilacs are prone to Armillaria, that can sometimes pinch a tree or shrub's top off pretty fast.