So I have now seen on two different occasions asian lady beetles on my eastern hemlocks that are infested by woolly adelgid. Does anyone have any success stories or literature on them being effective as biocontrol? I know there is a different non-native beetle being studied but I’m wondering specifically about the asian lady beetles.
Has anyone noticed them on their trees?
Thanks!
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A quick Google led me to some YouTube videos about this.
I hadn’t been aware, so thanks for bringing it up!
I’m in Northwestern Michigan with Woolly Adelgid
reported in several counties. The DNR asks us to look and report, but only mention the chemical treatment, so far.
There is a biological control using a beetle but I’m not sure how available that is to the public.
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If I recall correctly, the Asian Lady Beetle was purposefully introduced to America specifically for pest control of an aphid. It quickly grew out of control, killing and eating native aphids, butterflies, and ladybugs which led to its current status as an American invasive species So, at some point, it was widely accepted as biocontrol, but we decided it isn’t worth the harm it causes.
I personally will tear their wings off (so they can’t migrate) and use them as biocontrol against Oleander aphids if I find them already near my milkweed, but I would never purposefully introduce them somewhere else. It’s hard to say how effective it is since I also physically remove Oleander aphids myself, but there’s definitely a lot less aphids on my milkweed than the wild ones nearby. One time, I even had Oleander aphids go extinct from my garden for a full season, and I doubt I managed to spot and kill every single winged aphid and it’s kin all by myself
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There is a different beetle that is currently being studied for the purpose of biocontrol of the wooly adelgid.
Asian lady beetles are used highly by the horticultural industry as biocontrol inside of greenhouses.