Astronomy

On Sunday the 19th before sunrise look for the planet Venus near the waning crescent Moon in the east. Before sunrise on Tuesday the 21st and Wednesday the 22nd look in the south for the Orionid meteor shower.

Birds

Many kinds of waterfowl follow the St. Croix River on their way south. Look for Mallard and Wood Ducks, Red-breasted, Common, and Hooded Mergansers, and Canada Geese, among others!

Mammals

Raccoons prepare for winter in several ways. During the summer and fall they eat a lot to build up body fat which will help them survive when food is scarce. They also grow a thicker coat of fur to help keep warm. And they find a sheltered place to sleep such as a hollow tree or an underground den abandoned by some other animal. They sometimes share dens with other raccoons so they can share body heat. Raccoons are not true hibernators but when it gets really cold they enter a state called “torpor” in which they have a lower body temperature and slower heart rate, both of which help them conserve energy. It takes raccoons an hour or so to come out of torpor, often by violently shaking and contracting muscles to warm up and wake up. They may remain in a state of torpor for just one night, several days, or weeks, depending on the weather conditions and temperature. But even if they only go into torpor for one night, the energy they save is more than the extra energy it takes them to wake up.

Insects

Bees will remain active on sunny days through fall, coming out of their nests or hives to visit whatever plants remain in bloom. And you might see a few Painted Ladies on the wing – I’ve seen one as late as October 25th! Finally, be careful not to step on Woolly Bear Caterpillars when you’re out hiking. The woolly bears are looking for sheltered places to curl up for the winter; next spring they’ll metamorphose into Isabella Tiger Moths. Folklore has it that the wider the rusty-orange band on the middle of the woolly bear, the milder the winter. Longer black segments on the ends of the caterpillar are said to forecast a more severe winter. Fact or fiction? Note the relative widths of the bands on any woolly bears you see this fall, and then watch to see what kind of winter we have.

Plants

Cattails have gotten fluffy; within the fluff are the plant’s slender, dark brown seeds. And milkweed seed pods have lost their green summer color and turned brown. They have started to open and release hundreds of milkweed seeds, each with its own fluffy little parachute. You might even see a Milkweed Bug on the seeds!

Trees

This week’s featured oak is the Northern Red Oak. Like all red oaks, it has pointed lobes on its leaves. The Northern Red Oak is easy to distinguish from the Black Oak and the Pin Oak because the spaces between the lobes, or “sinuses”, are shallow, only extending about halfway to the mid-rib. The acorns take two years to mature, and the caps cover only the upper quarter of the nut. Northern Red Oaks like moist soils and can live for 100 to 150 years. Northern Red Oaks grow up to 70 feet in height.

And depending on what the weather has been like you may still see some brilliant red maples. The red color is revealed when the chloroplasts that make the leaves green in summer die off.

Weather observations

Here are some weather observations for this week from past years.

Friday, October 17	2024: gusty winds and in the 70s; 2004 and 2002: trace of snow
Saturday, October 18	2024: sunny and continued unseasonably warm in the 70s; 2021: temperature in the 70s; 2011: temperature in the 40s through the day
Sunday, October 19	2000: record high of 84°
Monday, October 20	2024: high of 81°, two degrees shy of the record; 2021: Rain and thunder through afternoon; 2020: record snowfall of 7.9 inches
Tuesday, October 21	2024: sunny and 70s, no frost as yet; 2002: Record 0.4” snow
Wednesday, October 22	2024: sunny, near 80°, with clouds late; 2013: frosty, with temperature in the 20s in the morning
Thursday, October 23	1995: record rainfall of 1.01”

Photo/Image credits

All photos copyright Nina Manzi, except:
Keith Henjum: Hooded Mergansers, Raccoons
Dean Lokken: Mallard Duck
Gary Sater: Red-breasted Mergansers, Wood Ducks