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aggierose_gw

Yellow Bugs with black spots on my roses!

aggierose
16 years ago

Hi All!

I'm new to this website and I can't tell you how happy I am to have found it! I decided to start a rose garden this past spring. I planted 10 rose bushes and everything is going ok so far. I am full of questions, but I will start with only one! My roses are covered with bugs that look like lady bugs, but they are more elongated, they are yellow instead of red, and they have 9 black spots on their backs. They are all over the actual rose blooms that I have. What are these bugs and are they causing any damage?

Comments (17)

  • dublinbay z6 (KS)
    16 years ago

    Can't remember what they are called, but my roses get them sometimes too, usually in late summer or fall. In my Zone 6, they do a little bit of damage, but don't seem to stay around for very long, so I mostly ignore them. Besides, I've never found anything to spray on them that I care to spray--and they can fly off quickly, so no point in spraying.

    That's the best I can do for you on them.

    Welcome to the world of roses. If it's not one thing, it's another--but we charge ahead determined to grow every rose we can anyway. LOL

    Kate

  • hoovb zone 9 sunset 23
    16 years ago

    Spotted cucumber beetle? Bad guys.

    Here is a link that might be useful: spotted cucumber beetle

  • aggierose
    Original Author
    16 years ago

    They are definitely spotted cucumber beetles based on the pictures you posted. The information stated that they will kill entire plants! How do I get rid of them? I sprayed insecticide last week, but it didn't seem to do any good.

  • lesdvs9
    16 years ago

    The squish them between fingers method works for me, I've even learned to do it without gloves on:)

  • cweathersby
    16 years ago

    I've got those same bugs. I've been wondering what they are...
    There are 3 or 4 beetles in each bloom, so thousands of beetles in my yard, and I haven't seen one tiny bit of damage. Not to the blooms, and definately not to the plants!
    I don't see any reason to spray an insecticide on them.
    Are you seeing damage from these beetles?

  • dublinbay z6 (KS)
    16 years ago

    I agree with cweathersby--any damage is so minor you probably won't notice it. Sometimes the petals on the blooms seem to be a bit looser and the bloom is not quite as long-lasting, but this is very minor and often does not happen at all. I know of no real reason to spray them. They are not even remotely like Japanese Beetles, for instance--just a very minor nusiance. An insecticide will probably do more damage by also killing off the good guys who then will not be there when you need them to get after the other bad guys.

    Seriously, they are mostly just an irritation. Don't sweat it--OK?

    Kate

  • jody
    16 years ago

    The dang things will chew holes in the rose petals. I am completely with lesdvs9 here - I squish them.

    When we moved here and I started the new garden, I had one whole blissful season without them. They found me this year.

  • berndoodle
    16 years ago

    There are different kinds of cucumber beetles. Ours are shaped like Lady Bugs and they do chew holes in rose petals. They are not the worst thing, not the best thing. They love yellow and apricot roses the best. I squish them but it's a losing battle.

  • susz52
    16 years ago

    In Ontario Canada we have regular orange Ladybugs and yellow 'Japanese' Ladybugs. The Japanese type were introduced and flourished here. The yellow type have not seemed to damage plant material, they are looking for critters to eat. The bad thing about the japanese-type is that they seem to swarm and they bite people where the North American type just toddles around eating aphids. Susz

  • berndoodle
    16 years ago

    Thanks for the information about the Asian Lady Beetle. A cucumber beetle is really much more greenish yellow and not hard to distinguish.
    {{gwi:341790}}

    Here is a link that might be useful: Asian lady beetle

  • dublinbay z6 (KS)
    16 years ago

    One time, and one time only (about 2 weeks ago), I saw the cucumber beetles chomping on one bloom. I waved my hand over them, and they instantly flew off--probably heading for some other roses. However, they did not chomp on the other roses, nor did they return to chomp on the first rose bush.

    They usually disappear after a couple weeks--whether due to a short life span or because some predator unknown to me shows up and gobbles them up, I do not know. Whatever the cause, they don't seem to be a serious problem or a long-term problem in my garden.

    Kate

  • sunnishine
    16 years ago

    mine are definitely cucumbers...I have had them all summer...but they do no damage like except what dublinbay said and don't eat holes in the roses.

  • aggierose
    Original Author
    16 years ago

    I am not noticing any damage from these pests. After I found out they are cucumber beetles I did some research. I found that they are known for carrying 2 different diseases that will kill the plant. I also found that they lay eggs in the soil and the larve feed on the roots of the plants. I read that they will cause rosebuds to not open and I do have a cuople of plants that are doing this. The buds just start to turn black and don't ever really open up to anything. I don't know if this is from the critters or something else. Has anyone else found that the cucumber beetles can be so damaging?

  • Maryl (Okla. Zone 7a)
    16 years ago

    Obviously others have not had a plague of cucumber beetles like I've had or they wouldn't dismiss them so easily. Like thrips, some years are worse then others but in a bad year they will shred every flower in sight. 2 years ago clouds of cucumber beetles (literally clouds) settled onto my fall flower display and within 2 days every mum, Helianthus, Aster and Zinnia was in tatters. My neighbor remarked that it looked like a plague of locusts had passed through. They also afflicted my roses, but with more petals the roses withstood the damage a bit better. In my area they are constantly present during the growing season, but fall is when their numbers can get out of control. I rarely do insecticides and it would have been particularly hazardous to do it when all the blooms were open as not only the cucumber beetles were present but also loads of bees, wasps, moths, butterflys etc. All I can do is pray that it doesn't happen that badly every fall.
    {{gwi:341791}}

    Cucumber Beetle eating a rose petal. Note how their eating pattern which can lead to the shredding pattern. They also drop down into the layers of petals and munch away out of sight.

  • berndoodle
    16 years ago

    Hah! Mary caught one in the act. They definitely do damage to rose petals They also spend a fair amount of time feeding on the pollen and probably doing a little less harm. There are probably different species around the country because they are here in NorCal from first bloom to last bloom. I see Mary caught one on a light yellow rose. They flock to the yellow and apricot roses.

  • Terry Crawford
    16 years ago

    These guys were all over my roses this summer; mainly munching on the pollen. Now I know what they are! They weren't picky on what color roses they hung out in since I have a lot of pink roses. Wondered what they were. Thanks for identifying them.

  • barbarag_happy
    16 years ago

    Here in our hot, humid coastal SE VA arboretum garden, roses are located next to a raised bed that's used for vegetables from time to time. We have observed cucumber beetles on our roses, but they are not in any concentration that would do any damage. Obviously, the rose garden is no-spray, located next to an equally-organic vegetable garden. Our two favorite strategies are to bombard invaders with a cold-water spray, and to hand-pick. Our general practice at the arboretum is to not treat ANY insect unless it is threatening to actually kill a plant. We had a young chestnut invaded by chewing caterpillars and treated with Ivory soap & water-- gone, never to return! The chestnut tree is fine now.