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What's eating my rose bush leaves? #869006

Asked May 18, 2024, 11:20 AM EDT

Hello! I am noticing very severe lacy leaves/white windows on my rose bush (photo attached). After a little bit of self research a likely culprit is Sawfly larvae. I was not able to find any of the larvae on the underside of the leaves but the damage appears to match their profile. I am wondering if you might help confirm from the provided photos and suggest a treatment However, it also appears that I have Lady Beetle larvae and eggs also on the underside of the leaves. I appreciate that any treatment to take care of the Sawfly larvae would also wipe out the Lady Beetles. I am wondering if maybe the Lady Beetles will take care of the Sawfly larvae if I just remain patient or if my rose will further decline if I do nothing. Very open to your advice Very respectfully, Carrie

Miami County Ohio

Expert Response


Thank you for your interesting question. Yes it appears that this

is typical of sawfly damage as they are a pest to a host of plants

this time of the year. Without seeing and actual larvae I cannot be

100% positive but the damage is typical. The presence of the lady

beetle larvae (Coleoptera Coccinellidae) would seem to confirm

this as sawfly larvae are one of their favorite delicacies! Perhaps

the reason you do not see any sawfly larvae is because the lady

beetle larvae have reduced their numbers.


  Any chemical weather synthetic or organic sprayed on the roses

will most likely affect the lady beetle larvae. There are however

systemic Termiticides (termite pesticides) that cam be applied as

a soil drench around the plant. The plant then uptakes the

pesticide and any insect feeding on the plant will be susceptible

to the pesticide. If you were to use this drench method



read and follow the label directions and be sure the product is



safe to use around your plant.

Bt (Bacillus thuringiensis ) which is a natural occurring bacteria

has no effect on sawfly larvae as they are not in the butterfly

family.

  I have listed a few links below that may be of interest to you.

Also listed is your County OSU Extension Service should yo desire

to contact them for possible help and further information.


  Thank you again for allowing us to help you with your gardening

questions. Here are some other helpful websites that may be of

interest to you:

BYGL
Newsletter: http://bygl.osu.edu/

OSUE
Fact Sheets: http://ohioline.osu.edu

State Master Gardener Volunteer website - http://mastergardener.osu.edu


Ask-An-Expert website - https://extension.osu.edu/ask-an-expert

Ask-A-Master Gardener website -
https://extension.osu.edu/https%3A/extension.osu.edu/ask-an-expert/ask-master-gardener-volunteer


Miami County OSU Extension Office

510 W Water St
Suite 250, 2nd floor
Troy, Ohio 45373

Phone:<personal data hidden>

Fax:<personal data hidden>

Link:
Visit the Miami County Office website



https://blogs.k-state.edu/kansasbugs/2016/05/18/rose-sawflies-out-with-a-vengeance/

https://extension.umn.edu/yard-and-garden-insects/sawflies


http://www.wildlifeinsight.com/sawfly-caterpillars-or-larvae/


https://biocontrol.entomology.cornell.edu/predators/ladybeetles.php




MGV Seneca County Replied May 20, 2024, 3:26 PM EDT

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