Afton State Park phenology, August 5 to 11

The days are getting shorter and animals are starting to migrate.




4 minute read

Afton State Park Visitor Center (Greg Seitz/St. Croix 360)


Jupiter and Saturn continue to rise earlier and earlier. Saturn comes up in the east around  8:45 pm, and Jupiter around 10:30 pm. August 11th is the Full Sturgeon Moon, which promises to wash  out the Perseid Meteor Shower this year. 


Some Robins have raised not one, not two, but THREE broods of young this year. The last  fledglings have left the nest by now, and they are forming flocks so the young birds can practice their  flying in advance of migration. Ruby-throated Hummingbirds like to nectar on red flowers and also pale  purple bergamot. If you’re wearing a red shirt they may approach you to see if you are a flower!  Hummingbirds are the smallest bird in Minnesota; adults weigh just over half an ounce. It would take  more than 150 birds to weigh one pound! Although hummingbirds are small, they are very fierce; the  Aztecs believed that warriors who died in battle would be reincarnated as hummingbirds. And keep a  look out for Gray Catbirds along the edges of the woods. They are gray birds with dark gray caps; their  most common call is a raspy mew that sounds rather like a cat. 

Amphibians and reptiles

Sunny days are a good time to watch for turtles and snakes basking. Reptiles  are “ectotherms”; they don’t generate as much internal heat as do mammals, which is why they are  active in the summer and not in the winter. The warmth of the sun also helps turtles digest their food.  If you see them basking on a log or rock please watch them quietly from a distance. 


Some of the many species of butterflies on the wing at Afton include the Tiger Swallowtail, the  Painted Lady, the Peck’s Skipper, and of course the Monarch, our state butterfly!

Look for grasshoppers jumping and flying short distances. They come in many colors! The Katydid is  also a grasshopper, and is sometimes called the Long-Horned Grasshopper. Ever wonder why you seem  to start seeing grasshoppers leaping and flying in July and August, and not earlier? Grasshoppers hatch  from eggs in the springtime, and as they grow they molt their exoskeletons, and a new soft one  underneath hardens. Each successive version of the grasshopper is called an “instar”. Grasshoppers  have wings only after the last time they molt; that is why you see grasshoppers flying short distances in  the late summer and fall, but not in the early summer.  


The parade of wildflowers continues! Look for Rough Blazing Stars, Prairie Onions, both Yellow  and Purple Coneflowers, Cardinal Flowers, Butterflyweed, and Common and Swamp Milkweed.  Butterflyweed, Common Milkweed, and Swamp Milkweed are all members of the genus “Asclepias”,  which is named after the Greek god of medicine, Asklepios. People used milkweed in the past to treat  lung diseases and to remove warts.

Weather observations

Here are some weather observations from past years 

Friday, August 52015: sunny and pleasant, temperature in the 80s
Saturday, August 62001: Record high of 99°; 2020: partly sunny, 70s
Sunday, August 72001: Record high of 98°; 2015: ½ inch rain
Monday, August 81894, 1914, 2010: Record high of 96°; 2014: high in low 80s; 2020: skies dark through day but only a few sprinkles
Tuesday, August 91947, 2010: Record high of 95°; 2020 thunderstorms off and on through day
Wednesday, August 102010: Record rainfall of 2.47 inches; 2020: 3/8” rain overnight
Thursday, August 111968, 2004: Record low of 47°; 2007: Record rainfall of 1.73 inches

Photo/Image credits

All photos copyright Nina Manzi, except: 

  • Jim Brandenburg, MN Conservation Volunteer: Ruby-throated Hummingbird
  • Dean Lokken: American Robin, Painted Turtle 
  • Jane Williams-Petersen: Katydid


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Afton State Park phenology, August 5 to 11