Field of Science

Aphids driving us buggy

Here in Lincolnland we live in the midst of the maize and soybean desert, so some side affects can be expected. Presently gazillions of aphids have descended upon us and their swarms shimmer annoyingly in the evening rays of sun as autumn advances. Swarms of aphids are so thick you can hardly breath, and please, do not ask a bicyclist to smile. Spider webs are filled with little tidbits, and the swordtails in my fountain pond are feasting upon thousands of aphids. These are not just any aphids, but soybean aphids, and this winged stage is seeking a tree upon which to mate and lay eggs for over wintering. But they are not just seeking any tree, but a buckthorn (Rhamnus), not exactly a common tree. One of my colleagues tracked down a buckthorn yesterday and its leaves were a mass of aphids, so there is precious little room at the inn for all those gazillions still looking. This massive population built up during favorable summer weather (cool, wet) will crash. But here's the amazing thing about such insects. The offspring of those few aphids (in comparison to the whole population) will disperse next spring seeking soybeans, and if favorable conditions prevail, their ability to reproduce could again produce such massive populations. If soybean aphids pose an agricultural problem, then perhaps buckthorn eradication will be proposed to break their life cycle, just as currants and gooseberries were eradicated to break the life cycle of white pine blister rust. In the meantime, these aphids are attracted to yellow and light green, so dress accordingly.

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