Q Being a sweet-corn eater for most of my 72 years, I have noticed that, regardless of how many rows of kernels there are on the cob, the number of rows is always an even number, anywhere from 12 to 20 rows. Why?
A Good observation! Each kernel on an ear of corn comes from an individual female flower that was pollinated. Like many things in nature that come in pairs (eyes, ears, genes, strands of DNA and such), the individual female flowers on an ear of corn occur in pairs. This two-by-two configuration of individual female flowers on an ear naturally leads to an even number of kernel rows in corn.
Rex Bernardo, professor, Corn Breeding and Genetics, University of Minnesota
Tiny brown bugs
Q Recently, my screens have been covered with tiny brown bugs so small they are able to make it through the fine mesh of the screens. Once in the house they are able to fly -- in a somewhat lethargic state -- and look a bit like a fruit fly. This happens only in very late summer or early fall, and more noticeably when it's warm. What are these bugs; what attracts them?
A They sound like hackberry psyllids. They are common this time of year, especially if there's a hackberry tree in your yard or neighborhood, said Jeff Hahn, assistant extension entomologist at the University of Minnesota Extension.
During the summer, they live in galls they produce on hackberry leaves. In fall, they emerge as gnat-like adults from these galls, and seek places to spend the winter, just like boxelder bugs.
The very small, dark-colored insects are difficult to keep out. They like to congregate on windows, Hahn said, and enter homes through screens, under siding and other small cracks they can find.
Fortunately, they are short-lived and do not reproduce indoors.
Psyllids are known to "bite." When they land on an object, they will probe it to see if it is food. People can receive a very short-lived pinprick as a result.
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