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bostedo

Anyone dealing with new crepe myrtle scale?

Has anyone found an effective treatment other than systemic pesticide for the crepe myrtle scale that arrived in north Texas a few years ago? We're a few miles west of the original infestation and they made it to our neighborhood last year. Two trees that need to be treated share a root zone with a pear tree, so would like to avoid resorting to a systemic if possible. The ants are helping a lot, but we've not been able to contain them with the common topical or mechanical scale treatments. Any suggestions will be appreciated.

Didn't get much of a response to a Pests & Diseases Forum post because is still too localized to Texas.

Here is a link that might be useful: Crepe myrtle scale: New pest for US?

Comments (14)

  • PKponder TX Z7B
    10 years ago

    I've not seen those here yet and I'm sorry that you are battling them. Scale is a tough pest to deal with and I would be tempted to go the systemic route.

    I have always liked the Bayer that is referenced in the article you linked to.

    This post was edited by pkponder on Fri, May 10, 13 at 10:24

  • bostedo: 8a tx-bp-dfw
    Original Author
    10 years ago

    Yes, the Bayer systemic is what we'll likely use. Besides, getting any pears off our tree is just a fantasy anyway as the squirrels take the few it produces.

    The following linked article says "it's hoped that adequate management can prevent it from spreading"... I seem to recall similar things being said about Fire Ants. Too bad, since Powdery Mildew used to be the only occasional problem we ever encountered with CM around the state.

    Here is a link that might be useful: Plant Health: Don't mess with Texas (Eriococcus lagerostroemia?)

    This post was edited by bostedo on Fri, May 10, 13 at 12:49

  • PKponder TX Z7B
    10 years ago

    I don't mean to be nosy but the article stated that this outbreak started in north Dallas, spread to south Dallas and now in the mid cities. Are you in one of those areas?

  • bostedo: 8a tx-bp-dfw
    Original Author
    10 years ago

    Was apparently first detected in Richardson in 2004. We're just west of Richardson... which is essentially the far north side of Dallas.

    Was originally mistaken as Azalea Bark Scale that had developed a taste for CM, so a lot of earlier info is tagged as ABS on CM instead of CMS.

    Here is a link that might be useful: Images of 'Azalea Bark Scale' on Crepe Myrtle

  • Lynn Marie
    10 years ago

    OK, I live in Mesquite and noticed something very similar on one of my crepe myrtles two years ago. It was pretty bad last year too. I went out and looked at the tree yesterday and noticed that it wasn't as bad, but I don't know if it went away for the winter and is on its way back or if it is just getting better. Since this tree isn't living up to its expectations, and the other one in the yard is doing fine, I may just dig it up to keep it from spreading. What do y'all think? Will that help, or is the damage done already?

  • PKponder TX Z7B
    10 years ago

    Lynnmarie, I'd be vigilant about checking the other crape that you do want to keep. Apparently the damage has not been life threatening to the trees and TAMU is on the investigative case, so there may be some options for treatment going forward. It sure is unsightly.

    Bostedo, if you think that just cleaning the affected areas could buy you enough time to harvest your pears? They should ripen by August if you can keep the squirrels off of them. When I commented about systemic, I had not read all of the articles.

  • bostedo: 8a tx-bp-dfw
    Original Author
    10 years ago

    In our location, lines of red carpenter ants on the trunks have been the first sign that a tree is infested. They go to work before the black sooty mold starts to appear on the distal branches. I believe their year-round diligence has kept us from getting anything close to the bad infestations shown in some of the photos: we're seeing scale throughout much of the crown, but not very dense in any particular spot.

    Aside from the odd looking black branches, the initial tree does not appear to have suffered too badly. Don't know if this would be different without the ants' help. Article seems correct about this rarely being fatal to an otherwise healthy/established tree. So, wouldn't remove a tree for this problem alone. CM is so commonly used around here that once the pests are in the neighborhood, eliminating one infested tree will probably not substantially lower the long term risk to the other.

    We have eight dwarf and standard CMs on the property, so am going forget about the pears this year and resort to the systemic to see if this can be brought under control without the need for annual applications. If not, it could become the excuse to replace 5 or 6 with something else.

    This post was edited by bostedo on Sat, May 11, 13 at 23:33

  • grinchis40
    10 years ago

    So that is what was all over my tree last year. The infestation was really bad. The bark was all black, the tree barely bloomed. Now this year, as I was trimming, I noticed alot of dead twigs. I believe it got sprayed with some liquid sevin last year and that didn't help. I'll be watching to see what works for you guys. By the way, I'm in the McKinney area.

  • PKponder TX Z7B
    10 years ago

    Sorry you are dealing with this pest too grinchis40

  • bostedo: 8a tx-bp-dfw
    Original Author
    10 years ago

    grinchis40, The euonymus scale we dealt with in Houston laughed at the topical sprays we tried, so can imagine liquid sevin wouldn't do much to these CM pests unless the life-cycle timing just happened to be perfect. Will post an update once we know how the systemic does.

  • jake01
    10 years ago

    Hi - I guess this discussion is still open to futher discuccsions?

    If so, I would like to say that for the past 2 years I did not know what was the matter with my white CM. I have 2 that where 1 foot tall when I planted them 16/17 years ago. I got them at home depot in South Alington as that is where I live. I read about home cures and they did not work. So I resorted to heavy duty sprays that worked for a while but the mist that fell on other scrubs killed them as well.. So I plunder on. After winter was over, and the first good day last Febuary, I got out the saw and cut my White CM back so far I hurt me to look at what I had did. I when to Home Depot and spoke to the a lady gardner as waus advised to use Bayer on everything incuding my Roses. Thus I have done. Roses are good now (had to cut back the climing one) and the CM are starting to push out the leaves and small branches. I walk out and inspect them almost every day since Febuary as well as the Roses and also my burr oak in the back yard as well as the two rose of sharons that have not bloomed once since I have had them, now 4 years, as the bug eat the new leave and the buds. I think now I have gone thru 2 bottles of Bayer. Only problem I have now it some little bug is eating new leaves on the rose brush's again, stripped them down to the vains and the branchs, I sprayed again last week before all the rain, and now I'm getting new leaves again. I'm new to all of this so the bug or scale on the cm seems like it kills every thing. Two familys on our neighborhood have cut down ther tall CM and did not treat them.. 2 others have cut down 15' foot tall trees in their yards. I'n not cutting down totaly if I can help it. Thanks you all for posting here. I had forgotten about this web site until tonight when I had to request help to log on agian. ....reb

  • ruthz
    10 years ago

    I believe I have this on 2 of my Crape Myrtles. They still look fine except for having the white spots and still bloom.
    Sounds like the best thing might be to just take them out. I don't use much of anything except neem oil or a soapy or garlic spray.

  • cordovalady
    10 years ago

    I just found these white spots on my crepe myrtle. I live east of Memphis, TN. I planted this crepe last year. It grew fast but didn't bloom & now that the leaves are gone I have found several of these white things on the limbs. I scraped them off, but would like to know if there is something I should treat the tree with now or should I wait until spring?

  • bostedo: 8a tx-bp-dfw
    Original Author
    10 years ago

    Thought I saw something about an effort to control a recent outbreak in Shelby county. Have you checked with your local county extension folks?

    Dormant oil may help, but will probably have to resort to a systemic if your goal is elimination.