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rose slugs...can I cut off affected leaves???

terry bartinson zone 3a NorthWest Ontario C
7 years ago
last modified: 7 years ago

Hi all. First post here. Hope someone can help please.

Got rose slugs bad on 2 bushes. It's mid June here in NW Ont. Not sure what to do. Should I cut all the affected leaves off...there are a LOT of them. Just leave them on now and hope for the best? I did spray for the first time yesterday with insecticidal soap.

In my defence, I get blackspot to some degree every year. So this year have been spraying with milk once a week for the last month or so. 2 weeks ago the leaves were perfect. Then I noticed some whiteish/grayish spots on them. Thought it was a residue from the milk. Then I saw some holes and thought they were cutter bees (which I knew were harmless). Wrong!! Discovered just a couple days ago a little green worm like thing on the underside of many leaves. Never had them before. Man, can those little buggers ever eat.

I'm sure these critters are rose slugs-the hairy ones. I've read there can be up to SIX infestations a year. Roses are flowering now, tons of buds yet to open. And they usually flower again later in summer, early fall. Don't want to lose them. Would appreciate hearing any suggestions regarding what to do at this stage of the game. Thanks.

Comments (9)

  • seil zone 6b MI
    7 years ago

    There are stronger chemicals you can use than the soap but as Jim said, they only work if they come in contact with the bug. So you have to spray every inch of the plant and usually more than once so you get any that hatch later. Most insects have a season and will eventually disappear on their own.

    Leave any leaves that are still green as they will continue to feed the plant. Eventually the damaged leaves will die and fall off on their own anyway. If a leaf is already severely damaged you can take it off.

    terry bartinson zone 3a NorthWest Ontario C thanked seil zone 6b MI
  • rosecanadian
    7 years ago

    When I see a sawfly mark on the leaves, I turn over the leaf and the ones around it. When I see the larva, I fold the leaf over it and squish it. You do have to look fairly often so that you don't have a major infestation.

    Carol

    terry bartinson zone 3a NorthWest Ontario C thanked rosecanadian
  • terry bartinson zone 3a NorthWest Ontario C
    Original Author
    7 years ago

    Thanks jim and seil zone. There is still a LOT of green in the leaves. Very few have been totally skelotized. So I'll just leave them on. Yes, I did spray undersides the best I could. I'm going to spray a few more times at least. My soap instructions says I can spray again a day after first using but I'm not so sure. Would you do that? Or better to wait a few days between sprays?

    seil...I read that Sevin and Malathion and a few others work. We have so many bees around yard I hate to use this stuff though. I did however read, as far as bees go, that it would be OK to use these after they go to bed, whatever time that is lol. If things worsen I'll try this and hope I don't kill off to many good bugs.

    THANK YOU for your thoughts. Appreciate you taking the time.

  • terry bartinson zone 3a NorthWest Ontario C
    Original Author
    7 years ago

    Thanks rosecanadian. When you say "sawfly mark" are you referring to the holes in the leaves...or is there something else? It didn't click in with me until too late that these were rose slugs as never had them before. Thought they were cutter bees. Judging by the holes in the leaves I've had a major infestation. Now I know what to look for next year anyway. Thanks for taking the time.

  • jim1961 / Central Pennsylvania / Zone 6
    7 years ago

    Harsh chemicals such as sevin etc. are overkill for rose slugs... Safer insecticide soap and Spinosad are effective if directions are followed. I'd wait alittle awhile before spraying with soap again...

    When you first start seeing rose slug damage you can actually pick them off the bush and kill or try hosing them off with water...But you need to catch them early before they cause to much damage. A lot times wasps, birds will eat them off your bushes also...

  • rosecanadian
    7 years ago

    You're welcome Terry. And, yes, I meant the holes.

    Jim - I've seen the little wasps (much smaller than normal wasps) hunting among the leaves.

    Carol

  • terry bartinson zone 3a NorthWest Ontario C
    Original Author
    7 years ago

    Thanks jim. Yes, I'm leery of Sevin, etc. I'll give it another 3-4 days before I do the insecticidal soap again. This is the first time I've had bugs like this so really wasn't cognizant of what was happening. Discovered them too late. If they come back again this year or early next year I'll be more alert and prepared. Thanks .

  • jim1961 / Central Pennsylvania / Zone 6
    7 years ago

    Sometimes I see our rose canes bouncing up and down... Usually its a small bird eating rose slugs and other insects off the roses...Yep wasps love to kill rose slugs...

    Took these pics a few years ago: