- My Forums
- Tiger Rant
- LSU Recruiting
- SEC Rant
- Saints Talk
- Pelicans Talk
- More Sports Board
- Coaching Changes
- Fantasy Sports
- Golf Board
- Soccer Board
- O-T Lounge
- Tech Board
- Home/Garden Board
- Outdoor Board
- Health/Fitness Board
- Movie/TV Board
- Book Board
- Music Board
- Political Talk
- Money Talk
- Fark Board
- Gaming Board
- Travel Board
- Food/Drink Board
- Ticket Exchange
- TD Help Board
Customize My Forums- View All Forums
- Show Left Links
- Topic Sort Options
- Trending Topics
- Recent Topics
- Active Topics
Started By
Message
Crepe Myrtles and black soot
Posted on 9/4/25 at 9:03 am
Posted on 9/4/25 at 9:03 am
I have 3 fairly large crepe myrtles that have been neglected for some time. This past winter I pruned them and then put down some fertilizer spikes in April and they have taken off and bloomed were looking beautiful. Now here at the end of summer all 3 are covered in black soot on the leaves, limbs, trunk, the grass under them is turning black, etc. It's just a mess. I've read that it is caused by some type of aphid or insect. As large as they are I don't think I can spray any type of chemical on them effectively. I'm thinking of using a mixture of dawn dishsoap and water in a hose sprayer and soaking the whole things down to smother the bugs causing the issue. (Read this online too)
Tell me where my strategy is gonna fail...lol. Thanks.
Tell me where my strategy is gonna fail...lol. Thanks.
7
Posted on 9/4/25 at 9:26 am to Canon951
I have the same thing on one of my crape myrtles and it has spread to a couple of the smaller shrubs that surround it. Interested to see the replies for a solution.
Posted on 9/4/25 at 9:32 am to Canon951
The scale insects and aphids feeding on the leaves of your trees are oozing juice which feeds mold. Go to a good nursery and get a recommendation for a systemic insecticide root drench used in your area. Also consider careful pruning to open the crown up to more light and air circulation. Be warned that many garden-care companies have no idea how to correctly prune crepe myrtles.
Go ahead and try spraying a Dawn solution. A landscape guy I respect swears by it for fire ants. It might work on aphids and scale.
Go ahead and try spraying a Dawn solution. A landscape guy I respect swears by it for fire ants. It might work on aphids and scale.
Posted on 9/4/25 at 9:42 am to Canon951
I have the exact problem as you. It was a mixture of aphids and white mold. I used the GardenSafe Fungicide3 spray attached to my hose twice so far over the summer and there is a day and night difference.
Posted on 9/4/25 at 9:47 am to Tygerfan
The systematic insecticide does the trick killing the bugs but it will not remove the black. You'll either need to scrub that off or just wait for the tree to shed on its own.
Posted on 9/4/25 at 9:59 am to ericw8036
quote:
I have the same thing on one of my crape myrtles
Same here, first time. Had no idea about this and noticed it mowing, was like what the frick is haunting my tree?
Also read the Dawn dish soap method. Maybe I’ll mess with it after Halloween.
Posted on 9/4/25 at 10:16 am to cajuns td
quote:
The systematic insecticide does the trick killing the bugs but it will not remove the black. You'll either need to scrub that off or just wait for the tree to shed on its own.
This.
That'll kill the scale... and winter will take care of the black. Do the drench again in the spring. Should clear everything right up.
Posted on 9/4/25 at 10:46 am to Canon951
Its called "crape myrtle bark scale".
Posted on 9/4/25 at 10:54 am to MemphisGuy
quote:
That'll kill the scale... and winter will take care of the black. Do the drench again in the spring. Should clear everything right up.
Nvm misread. Will buy the fertilome drench product and maybe do one application now then again in the spring. I have some neem oil. Will that help?
This post was edited on 9/4/25 at 11:21 am
Posted on 9/4/25 at 11:01 am to LSUDbrous90
quote:
Can I do the drench now?
I mean... you can... it's not ideal... they aren't actively growing anymore, or won't be for very long. Better to do that in the spring. Do a dormant oil spray now and wait.
quote:
have it die if thats even possible.
Eh.. it'd have to be pretty darn bad and go unchecked for a long time to kill the tree.
Posted on 9/4/25 at 11:16 am to MemphisGuy
You can also buy a thousand ladybugs to release on the aphids and they’ll feast.
Posted on 9/4/25 at 11:34 am to Canon951
I think you have missed the window for this year…the aphide]s and resulting aphid piss is already there. I have the same thing and we need to start the process to control aphids in the spring to prevent the problem altogether.
I like Meepole’s suggestion of buying some ladybugs had unleashing them. They can be had fairly cheaply,
I like Meepole’s suggestion of buying some ladybugs had unleashing them. They can be had fairly cheaply,
Posted on 9/4/25 at 12:59 pm to Canon951
I may try the soap solution this weekend and then get on it early in the spring with the products mentioned here. Thanks for the info.
Posted on 9/4/25 at 1:13 pm to Canon951
just cut the crepe down. those things are a pain in the arse.
Posted on 9/4/25 at 1:16 pm to Canon951
I had same issue last summer, trees never really recovered so we pulled them up this spring
If they are close to the house the black soot will get on your roof
Took a couple of times spraying it down to get the majority off
If they are close to the house the black soot will get on your roof
Took a couple of times spraying it down to get the majority off
Posted on 9/4/25 at 1:25 pm to Sherman Klump
quote:
just cut the crepe down. those things are a pain in the arse
Won't work. I cut down 6 trees about 10 years ago. Fought regrowth from roots for a few years and thought I finally won. Earlier this year I redid the flower beds and decided to till before replanting. Somehow that rejuvenated the old roots and they're growing again.
Posted on 9/4/25 at 2:18 pm to cajuns td
quote:
Won't work. I cut down 6 trees about 10 years ago. Fought regrowth from roots for a few years and thought I finally won. Earlier this year I redid the flower beds and decided to till before replanting. Somehow that rejuvenated the old roots and they're growing again.
Takes a lot of effort, but I've been successful. I cut them down at the base, dug around the roots as best I could like an archeologist, drill holes all over them, soaked with glyphosate, waited a couple days, soaked with kerosene and covered in scrap wood. Fire burned for like 2 days, but they were toast. I tilled what was left and monitored for a while before planting anything there. This was a few years ago.
Now I had another one in the yard I didn't do quite all of that to and I get shootups occasionally through the grass, but the mower gets them. You can't tell it's lurking underground beneath the lawn, but I know it's there.
Posted on 9/4/25 at 3:18 pm to Canon951
quote:
I may try the soap solution this weekend and then get on it early in the spring with the products mentioned here. Thanks for the info.
Go ahead and get some Neem or other horticultural oil (but preferably Neem) on it now. It'll do better on the scale than soap.
This post was edited on 9/4/25 at 3:19 pm
Posted on 9/4/25 at 3:25 pm to Sherman Klump
quote:
just cut the crepe down. those things are a pain in the arse.
No they aren't. So long as you don't commit Crape Murder.
They are low maintenance.... well, except for the Bark Scale, which is a relatively new thing...
Posted on 9/4/25 at 5:38 pm to MemphisGuy
Sorry if this is a dumb question but how do you apply it to a 20’ tree? With the soap I was thinking of putting it in an ortho dial sprayer hooked to the hose and just spraying the whole thing down. Does neem oil come in a sprayer you connect to the hose?
This post was edited on 9/4/25 at 5:54 pm
Page 1 of 2
Popular
Back to top
Follow TigerDroppings for LSU Football News