Afton State Park Phenology, Week of July 17, 2020

Prairie wildflowers are really blooming now and the pollinators are busy.




4 minute read

Trail along the St. Croix River at Afton State Park. (Photo by Greg Seitz, St. Croix 360)


Look for Venus in the east before sunrise, in a nice conjunc4on in the morning of the 17th with the moon and Aldebaran, one of the brightest stars in the sky. In the morning on the 19th the moon is to the left of Mercury, quite low in the eastern sky.

Saturn rises at sunset on the 20th and is out all night. Jupiter rises about an hour earlier so after dark you can stay up and watch the two giant planets move across the night sky.


Look for turkey vultures soaring overhead. You can tell them apart from eagles and hawks because: turkey vultures wobble from side to side as they glide, the feathers at the ends of their wings look ragged, and their wings are dark at the leading edge and lighter at the trailing edge. American goldfinches are one of the last birds to nest in our area. They use the fluff of field thistles in their nests, and also like to eat thistle seeds. And watch for great blue herons hear the water. In flight they have their heads tucked in near their bodies with their legs trailing behind.


Look for bats flying after sunset. There are fewer bats this year, probably due to a disease called “white nose fungus”. Infested colonies wake up from hiberna4on in the winter, which oAen causes their death. Enjoy the ones you see – they eat lots of mosquitoes! And watch for red squirrels, and deer moving quietly through the forest.

Amphibians and reptiles

Watch for snakes and turtles basking on sunny days. If you’re biking or hiking at AAon be careful not to run over or step on a snake.


The Painted Lady, Monarch, and Tiger Swallowtail are three of the many species of butterflies you may see sipping nectar from flowers at Afton this week.

Many dragonfiles and damselflies are on the wing. Dragonflies rest with their wings held open. Damselflies rest with their wings together. Look for soldier beetles climbing on leadplant flowers on the prairie, and along the river look for great clouds of mayflies flying upstream to mate and lay eggs. They only live for about a day as adults, and don’t even have any mouths because they don’t live long enough to need to eat anything.


Look for butterfly weed, yellow coneflowers, bee balm (also called wild bergamot or mondarda) and rough blazing stars blooming on the prairie.

You may still find ripe wild black raspberries – a tasty treat for hikers! Look for Monarch caterpillars on milkweed leaves. And you may see magpie inkcap mushrooms under pine trees – but don’t eat them, since they’re poisonous!

Weather observations

Here are some weather observa4ons for this week from past years

Friday, July 172015: humid with high in the 80s
Saturday, July 182012: first day since late June with temperature below 85°
Sunday, July 192015: mid-60s in the morning, rising into the 80s with dry air
Monday, July 202013: High in the 70s
Tuesday, July 212012: 70s with two waves of thunderstorms through day
Wednesday, July 222014: Partly cloudy, high in 80s
Thursday, July 232013: Pleasant day, high in the 70s; 2012: high of 96°

Photo credits

All photos copyright Nina Manzi, except:

Dean Lokken: American Goldfinch, Red Squirrel, Turkey Vulture
Deborah Rose: Bat
Jane Williams-Petersen: Magpie Inkcap Mushroom, Wild Black Raspberries


You may republish this article online or in print under our Creative Commons license. You may not edit or shorten the text, you must attribute the article to St. Croix 360 and you must include the author’s name in your republication.

If you have any questions, please email


Creative Commons License Attribution-ShareAlikeCreative Commons Attribution-ShareAlike
Afton State Park Phenology, Week of July 17, 2020