Hi Greenman,

Shumard Red Oak is usually pretty disease-resistant except for one thing, and that one thing is a doozey, so we'll leave it for last.

If the appearance of the beetles and the leaf-drop seem related time-wise, i.e., that first you saw the beetles around for a while and then you saw the green leaves dropping, then perhaps there is a link between the two. How small are these beetles? Are they the size of ladybugs, for example, or are they almost as large as Japanese Beetles? Or, maybe they are mid-sized like May beetles/June bugs? The most important thing at this point likely would be to ID the beetles so you could determine if they are the problem. It may not be that the beetles themselves feed on the tree enough to hurt it, but rather that they might vector disesase.

To take this discussion in a different direction, do you feel like you kept the tree adequately moist all of last year? Sometimes drought damage in trees is slow to show itself. That's because trees can live off stored energy for about a year, so that even when they are drought stressed, it will seem like they came through the drought and survived it, and then from several months to a year or more later, the tree will go into a decline and die. That's just something to keep in mind, and if you feel like the tree never got desperately dry, you can discard this as a possibility.

Now, let's talk about the doozey of a problem I mentioned earlier. Are you familiar with oak wilt disease? I am not sure how widespread it is in Oklahoma, or if it is at all common here, but in Texas, where we lived before moving here, it was then and still remains almost epidemic. Unfortunately, once an oak tree contacts oak wilt, its odds of survival are slim to none. I am not saying that your tree has oak wilt, not at all, but just that it is one of the possibilities you need to be aware of and need to watch for. I'm going to link something below about oak wilt, and it does discuss the role of sap beetles and oak bark beetle that can spread oak wilt. You might want to read that part of the link, and look at the line drawings of the beetles. Then, if it were me, I'd Google to find color photos of those beetles and make sure they are not what you're seeing on the tree.

A healthy Shumard Red Oak shouldn't just be dropping green leaves randomly. However, if by chance you've recently had very heavy rainfall and the soil stayed waterlogged for a while, I think the leaf drop could be a reaction to that.

I wouldn't get panicky at this point if it were my tree, but I'd be watching carefully. I'd be watching for a discernable pattern of leaf drop--like whether or not all the leaves are falling from one limb or set of limbs or from only one side of the tree, or from all over the tree. Clues like that can be helpful in figuring out why the leaves are dropping.

Also, I'm going to assume no one has used a weed-n-feed product on the ground in the drip line of the tree's canopy.

Shumard Red Oak is one of my favorite trees and we have several of them in our yard, and more scattered around the property and they usually are very healthy trees, so whatever is going on, as long as it isn't oak wilt, isn't likely to be a life-or-death issue.

Dawn

Here is a link that might be useful: Oak WIlt

Thanks, Dawn. I looked into oak wilt, and that doesn't *seem* to be the problem, but who knows... I'll read some more.
The beetles are about the size of a June beetle, maybe slightly smaller, black with tiny white dots on their backs.
Come to think of it, several weeks a go I did spot treat some bermudagrass (!!!) with Round-up that was coming up in the mulch ring, but I've been doing that for years around all my trees/shrubs and it never hurts them, though maybe it did this time as I gave the bermuda a good dousing..

You're welcome, Greenman.

Hmmm. I haven't seen beetles like that, but I'll look at some of the Shumards close to the house tomorrow and see if I happen to have any of those same beetles on my trees.

I don't think Round-Up would hurt your tree as long as you did not spray any of it on green parts of the tree. Round-up degrades very quickly in soil and is not taken up by tree roots in the soil.

Yea, after looking around I think the beetles I'm seeing are sap beetles, and I remember seeing them last summer, too.
The tree actualy looks fine - not bare at all and even has new healthy-looking leaf growth. I just happen to notice everyday there are quite a few green leaves in the yard below it - and this is someting that it never did before.
The only thing I did different this spring was apply a tree fetrilizer--the kind you stake in the dripline--which I did to all my young trees/shrubs this spring.
I suppose it is also worth mentioning that my neighbor has a 3 year old river birch transplant whose leaves are yellowing and dropping fairly fast (much worse than my shumard), but that tree has been neglected for a while and wasn't watered at all during the drought last summer..
GM

Every river birch I've seen around here is either dead or half-dead since last summer. They really don't like the kind of heat and drought we had last year.

The sap beetles on your tree are not good news, but I am not sure at what point they become a big enough issue to require that you take some sort of action. I usually don't do anything unless I see significant damage. I don't know for sure if green leaves dropping is significant in and of itself. For example, it could just be that you had a nice rainy winter and spring so the tree leafed out with oodles of foliage, and then in April or May, the rain has refused to fall. That might cause the tree to decide it grew too many leaves in the cool, rainy weeks and cannot support them in the hotter, drier months, so it drops them. Well, it is not a conscious decision a tree makes, but you know what I mean.

I don't think a tree fertilizer stake, if used following label directions, would cause leaf drop. Those fertilizer stakes are designed with the tree's needs in mind, so shouldn't overfeed with anything that would cause leaf drop.