3 Year-old live oak..What's wrong w/ my tree?

[Bill Freedman]

Hello,

I've got a 3 year-old Live Oak....in the North Dallas area.....and in the last month..a sort of bulbous, black, growth has begun to appear. Can anyone identify what this might be? My neighbor (whom may be a bit paranoid) was thinking "Sudden Oak Death"..but I'm under impression that that has not really hit my area....

I've posted some photos...

help would be appreciated...

Thanks,

sV

[Pat Kiewicz]

I think your oak is infested with some sort of scale insect.

Scale is usually treated with a dormant oil spray (too late for that), but there may be some sort of systemic insecticide that could control them.

avoid line-wrap, use your tree is small enough and you are determined to protect it, you could actually go through and pull off all the visible adult scales, then wash the tree down with insecticidal soap and rinse. Then next winter be sure to give it a dormant oil treatment.

I know one person who gave up the fight and removed a scale infested magnolia tree.

I managed to eliminate a scale infestation from a small plum tree, but it's never been a particularly healthy tree even after that.

[Jangchub]

Try to scratch it off. IF it comes off easily, inspect the thing and on the underside you may see parts of the insect called scale. You can treat that with insecticidal soap. Just go over to Rohde's and bring some of what's on your tree in a tightly closed jar or bag and make sure scale is what you have.

[Treedweller]

My first instinct was wasp galls, but looking at the photos, I think not. Perhaps some kind of scale insect?

a couple off and see if there are legs and such underneath.

If so, treat with dormant oil/horticultural oil/Volck oil.

Keith Babberney ISA Certified Arborist #TX-236AT

[Latosha Washington]

That looks pretty big for a three year old oak!

[dwheeler]

Without specimen in hand, it's impossible to be sure.

But I would guess it _could_ be Daldinia concentrica or some similar species of fungus. If so, you're have some significant damage to the tree recently, either by colder than normal weather conditions, or by something striking the tree.

Daldinia concentrica is just one of several related species, many of which are little known at this time. It is also sometimes called "King Alfred's Cakes", or "Cramp Balls".

Assuming that you have detached one of the things from your tree and sliced it open, D. concentrica looks like a layered ball growing outward from the wood. I have seen it growing on wood used to grow shiitake (Lentinula edodes) as well as wood inoculated with Pleurotus ostreatus (Oyster mushroom).

Let's hope it is not Phytopthora (Sudden Oak Death).

Daniel B. Wheeler

[morninglori]

Hey Dallas, looks like scale. No Sudden Oak Death in our area for some time. Scale is pretty awful stuff though. Take a piece to Nicholson Hardie on Lovers at Inwood and let them give you something to get rid of that awful stuff.

-Arlington