Crepe Myrtle

[trenad]

Hello All!

Last summer my CM got Bark Scale.

I cleaned and treated as advised by TA&M. They seemed to clear up and then they were swarmed with black wasps (I think). We treated those and then winter came.

2 of my CM have growth at the bottom. 1 does not. They all still have the black coloring at the top of the branches. The black tops seem to be dead.

What should I do?

Pictures attached.

Thanks,
Trena in Texas

 

[Chuck]

Hello All!

Last summer my CM got Bark Scale.

I cleaned and treated as advised by TA&M. They seemed to clear up and then they were swarmed with black wasps (I think). We treated those and then winter came.

2 of my CM have growth at the bottom. 1 does not. They all still have the black coloring at the top of the branches. The black tops seem to be dead.

What should I do?

Pictures attached.

Thanks,
Trena in Texas

Get a knife and scrape off a little of the black tops until you go through the cambium layer of the limb. If it shows any greenish color don't worry about the black, the limb is still alive. IF, IF the limbs are dead remove them. CM's are on their rootstock so the growth at the bottom will grow into a tree. You just have to be judicious in your pruning and leave only 3 or 4 of the best straightest limbs, but this is only if the top of the tree is dead. I have never seen a CM die from insects or disease. Only from not being watered or from flooding. I live in South Central Texas and my CM's are showing zero signs of budding but I expect them to any day now so don't worry if the tree isn't doing anything now. The black stuff is probably just sooty mold caused by the scale. How did A&M want you to treat the tree? I wold like to see close up pictures of the black stuff and pics of the limb after you scrape off the black stuff.

 

[trenad]

Here is a link to the recommended treatment. I live in North Texas. I will send more pics tomorrow.

https://agrilifecdn.tamu.edu/citybugstest/files/2010/05/EHT-049-Crape-myrtle-bark-scale.pdf

 

[Chuck]

Here is a link to the recommended treatment. I live in North Texas. I will send more pics tomorrow.

https://agrilifecdn.tamu.edu/citybugstest/files/2010/05/EHT-049-Crape-myrtle-bark-scale.pdf

Thanks for sharing this. Truthfully, I had never heard of bark scale on CM,s. On my trees I got aphids once but that has been all. This is not good as the link states oils don't work and Oils have been the main treatment for scale forever. However, A&M has long been known as a pro chemical school so I take much of what they say with a grain of salt. CM,s have a loose bark habit so spraying with anything when the bark is loose and cracking will probably be futile at best and thus the systemic use is recommended. Guess I better go check my trees.

 

[trenad]

Ok, I did the scratch test and I do see green, however if you cut the branch horizontally it looks dead.

Here are additional pics.

 

[Chuck]

Ok, I did the scratch test and I do see green, however if you cut the branch horizontally it looks dead.

Here are additional pics.

The interior of a limb always looks dead. Only the cambium layer has any green. I couldn't tell much from the pics except for the stratch test and it looks fine. Just give your tree a little time and see what buds out. Anything that doesn't remove it. That sooty mold will eventually go away but if you want you can get a product that will help get rid of it it is called Plant Wash and is sold by Soil Mender.