Saturday, June 19, 2010

Bugs and beetles, good and bad

This is Entomology Week for me, since I'm taking a class on Tuesday with Dr. Mike Raupp - so it's fortunate that I have some bug pictures to show you! First exhibit was photographed in the demo garden this week and ID'ed for us by the friendly folks at HGIC as a two-spotted stink bug.

It is a great bug to have around: a predator that feeds on Colorado potato beetle among other insects. These beetles are making their annual attack on the potato bed. They are not hard to keep at bay if you go after them a couple of times a week at least, using the Integrated Pest Management technique known as squishing. If you forgot your gloves or are too squeamish, drop them in a bucket of soapy water. Here are images of last year's beetles, adult and larvae:









Barbara Knapp showed me a larva that was a considerably brighter orange than the others, and also said that the larvae on the blue potatoes (which seem to be more attractive to the pests, though mine at home haven't been attacked yet) were more purple in hue. You are what you eat, I guess.

Another stink bug everyone's been seeing a lot of (and I can't believe I don't have a photo on hand since I had a couple hundred of them in my house this winter) is the brown marmorated stink bug, which you can find information about here and here. I think I saw one in the demo garden this week, but it got away before I could positively ID it.

Harlequin bugs also belong to the same general group of stink bugs and they are nasty suckers - literally; they suck plant juices, especially from Brassica family plants. We just saw our first for the year in the demo garden, visiting a broccoli raab. I bet they'll be all over the kale next week. Here's a photo from last year:

And to end on a positive note, while I was photographing the parsnips I caught a few long-bodied beetles collecting nectar and pollen. I meant to get around to finding out what they were, when the IPMnet weekly update came out with Paula Shrewsbury's explanation. Here's my beetle:

It's a soldier beetle, an important pollinator (adults) and predator (larvae). I believe mine is the margined leatherwing. Remember to add lots of flowering plants to your vegetable garden (or, in this case, plant biennials that mysteriously go to flower in their first year) to attract beneficial insects. Small-flowered plants are particularly valuable in bringing in many predatory insects.

Harlequin bugs by Barbara Knapp, potato beetles by Nick Smith, two-spotted stink bug by an anonymous benefactor.

2 comments:

  1. you can leave me a email at painter_in_oils_925@yahoo.com

    i have potato beetles eating on my cantaloup plants
    & on my green pepper plants i didn't want to kill them tho because i think they are all on their for a reason maybe they are eating mites i don't know but anyways as i was looking at all of the potato beetles
    i found a longer beetle that looks some what like that 2 spotted beetle you have above but mine is a dark greenish gray color

    i don't think that i would like to be smashed
    just because im eating on a plant i just don't
    like to kill them like that or any of them
    i just let them be but i will remove the leaves that have the eggs on them i have to say i think aphids are the worst

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  2. Colorado potato beetle feeds mostly on potato, a bit on tomato and eggplant and very rarely on pepper. it does not feed on melon or squash. You may be seeing squash beetles. They lay clusters of very small bright yellow eggs.

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