I am in Texas. You are right. My lawn mowing guy sprayed weed killer in my flower bed and most likely in and around the bottom of the tree trunk. Did that cause it? If so, what do I do?

it should have had no effect on bark ... nor should it have been such a complete dump.. to go thru the soil ... unless he really poured it on ...

but drift is a common problem... i hope he was smoking while he was at it ... to offset covering himself and inhaling the fumes ... [thats sarcasm]

even damaged leaves photosynthesize ... and i consider .. trying to be optimistic.. this rather minor superficial damage ... but you are going to have to look at it.. until they fall off ... probably generating a good hate on this guy.. all summer long ....

but i am sure others will have other opinions...

i hope you got a new guy.. i am glad you didnt call him a gardener ....

ken

ps: all leaves eventually fall off.. i have no experience with evergreen oaks.. if that might make a difference.... as i am relying on your ID ....

The other thing I did was dumping the left-over weed-and-feed in and around the bottom of the trunk (I don't know what it is called - you know - the raised mulched area around the trunk) :-). I do that pretty much every time when I fertilize my lawn (which is no more than a couple of times in a year), but maybe I dumped too much leftover this time?

Live oak and it's weed killer, never ever spray weed killer around trees, it will kill them every time - try to remove all the mulch and as much dirt from around the live oak and replace - hope for the best. Weed and feed is not for trees - it says it right on the label.

You can remove the mulch but don't bother with the soil - removing the soil will likely do more harm to the tree than the weed killer (if that in fact was the problem). Just water the tree surrounds thoroughly to flush the pesticide down into the soil beyond the roots.

I'd suggest you seriously reconsider the use of weed and feed products. Not only are they a notoriously inefficient and expensive way to deal with lawn weeds but they are a major contributor to water pollution (including drinking water). And if you have pets or small children, they can be harmful as well. And many W&F products contain atrazine, which is documented to have an adverse affect on live oaks, although it will fall far short of killing them. Just use the lawn fertilizer of your choice judiciously (personally, I'd prefer to go organic) and then spot treat for any weeds or you can remove them manually. And whatever you do, never "dump" left over fertilizers or pesticides. Dispose of them responsibly via whatever hazardous waste disposal programs your area offers.

Finally, a 'lawn guy' spraying weed killer in a flowerbed is a recipe for disaster. If it managed to drift far enough to do foliar damage to the oak, think what it might be doing to the other plants in that bed. Obviously the needed care to apply the product safely and according to label directions was lacking. Either ask him to remove the weeds from the bed manually or do it yourself - pulling weeds can be rather therapeutic....you kind of get into this zen-like state :-) Then mulch the cleared out bed well to keep the weeds from returning.

Slightly OT, but "weed and feed is far and away the least effective, most polluting, and least efficient way to direct herbicide molecules at the weeds in your lawn. Think about it: In order for the "weed" part of this product to work, enough prills or particles of the material must stick to the foliage of the target weeds to deliver adequate chemical to kill said weeds. This means a great deal of what is applied to the lawn is wasted and/or ends up in our waterways, etc. By contrast, if one simply fertilizes their lawn and then does a separate spraying of liquid broadleaf herbicide, liquid being much more active and efficient, you will have both used less actual chemical active ingredient, plus also put it right where it needs to be to do its work-on the leaf surfaces of the weeds. Convenience is often given as the reason for the creation and marketing of weed and feed products, but they're very-nearly a scam IMO.

+oM

I think this is probably a natural nuisance condition like a leaf blight rather than chemical injury. If there is a fully funded Texas Cooperative Extension (or equivalent) office available to you you should probably present them with samples before deciding you know what is going on.

I'm with Embo- does not look like herbicide damage. Affected areas are too well-defined.

Not familiar with diseases of live oaks, but if it were on pin or shingle oak, I'd be thinking bacterial leaf scorch or some similar bacterial or fungal infection.

"Live oak and it's weed killer, never ever spray weed killer around trees, it will kill them every time"

^ This is false. Roundup (glyphosate) used around the base of trees will not do them any harm whatsoever. However, granular "weed & feed" products containing atrazine, 2-4d, or dicamba should not be used within the root zones of trees.

Like the previous posters, I do think this is just oak leaf blister, commonly seen on Water oak, Laurel oak, and Live oak along the gulf coast. Although unsightly to us, it does the tree no harm.