Need help with Red Oak die-back problem

[mmcd]

A red oak plant in my backyard is declining rapidly after putting vigorous new growth this spring. It started with wilting, browning and dropping of new growth leaves in early June, and worsened now with many branches shedding mature green leaves. Please see the attached pictures below.

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I noticed that a few leaves are disfigured, and a few have numerous tiny holes but, on the whole, the leaves don't seem to match symptoms of any specific oak disease. After first noticing the problem 5 weeks ago, suspecting a fungus problem, I cut the damaged ends, sprayed a 3-in-one pesticide/fungicide a couple of times. I also tried to revitalize the plant by putting Miracle-Gro Tree and Shrub fertilizer spikes (10), and have started watering in between sprinkler days. The plant didn't need any special watering before. We are in Dallas area and had some rain in spring and watering doesn't seem to be the issue. My sprinklers run twice a week for 15 minutes. Nearby trees planted last year have soaker-hose around them, and are watered every other day.

Now, in the last 2 weeks, many mature green leaves have started falling. Many leaves on the tree have dried completely and started falling. Two days ago, I notices some dark red/brown spots with some wet secretion; seemed like canker sores described in Oak diseases websites.

This tree was planted about 4 years ago before we bought the house last spring. The plant was growing well until 6 weeks ago and have grown three to four feet this year.

We have heavy clay soil.

Thanks in advance.

 

[Raintree]

The leaf drop & tip pruning looks to be a nuisance squirrel activity. The bigger issue is that bleeding canker on the trunk, do some research on Phytophthora, you may wany to have your Oak looked at. Phytophthora Bleeding Canker | UMass Amherst Landscape, Nursery & Urban Forestry Program

 

[mmcd]

Raintree, Thanks for your quick reply. The leaves shriveled and fell off, and I pruned the tips to control any fungus as suggested on a Texas A&M site.

However, the canker symptoms do match the description on the link you gave. Now my question is how to go about fixing/controlling it. There don't seem to be many good options.

The leaf drop & tip pruning looks to be a nuisance squirrel activity. The bigger issue is that bleeding canker on the trunk, do some research on Phytophthora, you may wany to have your Oak looked at. Phytophthora Bleeding Canker | UMass Amherst Landscape, Nursery & Urban Forestry Program

 

[Raintree]

mmcd, I suspect this pic is bleeding canker. It needs to be confirmed by a pro on site before a course of action is put in play. Also you may have something else going on with your tree like Oak Wilt that needs to be properly diagnosed.

 

[mmcd]

That's what I am afraid of. Thanks. I will be getting a proper diagnosis.

mmcd, I suspect this pic is bleeding canker. It needs to be confirmed by a pro on site before a course of action is put in play. Also you may have something else going on with your tree like Oak Wilt that needs to be properly diagnosed.

 

[treeseer]

To diagnose, the arborist will need to see the base of the tree with the root flare showing. Could you post a pic of that area?

Bleeding canker best treated by sterilization and cauterization.

 

[mmcd]

To diagnose, the arborist will need to see the base of the tree with the root flare showing. Could you post a pic of that area?

Bleeding canker best treated by sterilization and cauterization.

Hi Treeseer,
Sorry for the delay in responding. We just had twin boys and been quite busy with them.

Hoping to get the pics uploaded in the next day or two. Thanks for your help.