Agggh. We experience “I will ask Lowenfels about it” aphid infestations every few years. This is one of them.
We always have aphids around. They are normally kept in check by their natural enemies. Around here these include wasps and yellow jackets. One big reason you see so many this year is because they are feasting on the explosion of aphids. So are lacewings, hover flies, midges, damsel and big-eyed bugs along with several beetles. And, of course, birds.
OK, but these aphid predators are also around all the time, so what gives? Why this year? The stock answer has to be there were favorable environmental conditions. These are all outside of your control, of course.
There are a few things within your control that may be contributors, however. Starting with the spraying that is going on because of spruce bark beetles. These sprays kill aphid predators. I am convinced they are a big factor here. And for those who understand, what do you do when you get a notice that your neighbor is going to spray? Some neighbor. Loves their car more than you or the kids in the neighborhood, because I can tell you no trees will die from aphids.
Then of course, the circle widens when people start to spray for aphids. It only ends up intensifying problems. When will we get that if we tip the natural balance enough we destroy the solution to the problem? Spraying your yard will not help things.
I sure wish we had more birds that would eat our aphids. Alas, Alaska is running amok with feral cats, and no one wants to admit that they have decimated bird populations. Cat owners are appalled to be called out, and most are fully responsible, but it is a problem way out of hand. The main topic on every internet community bulletin board is cats.
The best remedy for your yard is the safest: a hard blast of cold water. It will knock them to the ground, and while water won’t kill them, it messes them up. It is difficult to get up into a 30-foot birch, and a hard, cold spray can damage delicate flowers. There are limits, but you will at least feel better without doing any damage to you or your neighbors’ health.
Next: lady bugs? In almost all instances, they just fly away when released. Try them in a greenhouse — and I stress “try” — but they are pretty much worthless elsewhere, in experience.
Insecticidal soaps and Neem oil will clean things up. They are great on meadow rue, the No. 1 attracter of aphids, but again it it is hard to get these high into trees. Even if you could, they, too, will affect some of the predators.
Onions, chives, garlic and radishes are supposed to keep aphids away from plants in your vegetable gardens. I am not sure any of these work. It is a good thing radishes grow so darn fast, however, so you can test to see for yourself.
The best advice regarding aphids? Don’t park your car under trees.
Finally, I don’t repeat columns, only subject matter. I wrote on the subject of aphid back in July of 2018, and given the miracle of the internet, it is available for those who need to refer to it again. In the meantime, consider how you deal with aphids. The only ways must be non-toxic. That is the rule.
Jeff’s Alaska garden calendar for the week
Spraying: One more time. Do not.
Alaska Botanical Garden: Summer activities at alaskabg.org
Tomatoes: Staked yours yet?
Peas and other climbers: Staked yet?
Delphinium, peonies: Staked?
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