Afton State Park Phenology, Week of August 14, 2020

The first signs of fall are visible, as squirrels gather walnuts and some bird species begin staging for migration.




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Footbridge in Afton State Park. (Photo by Andrew Pritchard via Flickr)


Look for the moon just below Venus in the eastern sky in the evening on the 15th. Look for Jupiter and Saturn in the night sky; they’ll be more than halfway across from east to west by midnight. Red-colored Mars will follow them across the ecliptic after about 11 pm.

“Ecliptic” is the word for the imaginary path that the planets and the moon more or less appear to travel from east to west across the sky from our vantage point here on earth.


Tree swallows and barn swallows are all done raising young and are about to migrate south. Looks for groups of them gathering on utility wires. Eastern bluebirds will be with us a while longer, and turkey vultures soar overhead. American goldfinches are late nesters, waiting until thistles bloom. They use thistledown to line their nests and feed their young thistle seeds.


Squirrels begin to prepare for winter by gathering black walnut seed pods and acorns.

Amphibians and reptiles

In the early morning hours you may see young tree frogs climbing windows in search of insects. Frogs climb up glass using sticky pads on their toes. Or you may see them hanging out in the shade of milkweed plants or just about anywhere – keep your eyes peeled! They can change color from gray to green.


Monarch butterflies will start south soon, and will begin roosting in groups soon; look for them on cool mornings before the air has warmed up enough for them to be active. Also look for common sulphurs on the prairie and mourning cloaks in the woods.

Some insects are very small, like the colorful sharpshooter leafhopper. The leafhoppers are members of the group called “true bugs”, which all have sucking mouthparts. Unlike many other insects, true bugs and also grasshoppers undergo only an incomplete metamorphosis and do not have a larval form. Instead a “nymph” which is a miniature version of the adult hatches directly from an egg. As the insect grows, it molts its exoskeleton and a new soft one underneath hardens. These in-between forms are called “instars”. The grasshopper shown here is an instar and not an adult, which you can tell because it doesn’t yet have any wings! The wings will develop the last time it molts.


Look for Joe-Pye Weed and Ironweed in wet areas, white snakeroot and boneset along the edges of the woods, and blue vervain and prairie onions on the prairie. And thistles are blooming; American Goldfinches use thistledown in their nests and feed the seeds to their young.

Weather observations

Here are some weather observations for this week from past years

Friday, August 142009: Hot and humid with high in the 80s
Saturday, August 152010: hot weather breaks today with a high in the 70s
Sunday, August 16Record 1.97” rain in 2002
Monday, August 172011: 1 3⁄4” rain from an overnight thunderstorm
Tuesday, August 182008: high near 90° but not too sticky
Wednesday, August 19Record 3.19” rain in 1997
Thursday, August 202015: sunny and pleasant with high in the 70s

Photo credits: All photos copyright Nina Manzi, except: Dean Lokken, Turkey Vulture
Gary Sater, American Goldfinch, Eastern Bluebird


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Afton State Park Phenology, Week of August 14, 2020