The flight speeds of ruby-throated hummingbirds are but one thing that makes them remarkable.

Late June and into July is nesting time for these summer visitors to Minnesota.

Among hummingbird species, only the ruby-throated hummingbird nests east of the Rocky Mountains. Banding records tell us that the hummingbirds we see in our yards may well return next summer and perhaps for several more. The tiny ruby-throats are about 3 inches long, with an average weight of 3.4 grams. It would take about 130 of these birds together to weigh a single pound. Metallic green above and white below, the bird gets its name from the ruby-colored throats of the males. Their top flight speed is just below 30 miles per hour.

Survival for a hummingbird depends on fast movements and courage. They can hover, move backward and dart forward at high speed to outmaneuver other birds. Being aggressive in defense of territory, they will go after much larger birds such as crows and blue jays, using their long, needle-sharp bill as a dagger.

Ruby-throated hummingbirds are a joy to watch.

I still am thinking about those pesky deer flies I wrote about in a previous notebook. Deer flies are hitting their population peak and are bothering people, in addition to dogs and other animals. No wonder whitetail deer head for lakes to get relief from these pests.

Some other observations:

Numerous Japanese beetles (an invasive species) are feeding on roses, grapevines, linden trees and many other plants.

Mulberry trees are common in the Twin Cities, Mankato and many parts of southern Minnesota. Their aggregate fruits, about a half-inch long and initially white, then red and then becoming nearly black, are juicy and tasty. They are a popular food of songbirds in early summer and well into July. Gray catbirds, Baltimore orioles and cedar waxwings relish the mulberries.

Jim Gilbert's observations have been part of the Minnesota Weatherguide Environment Calendars since 1977, and he is the author of five books on nature in Minnesota. He taught and worked as a naturalist for 50 years.