Argiope spider

August phenology

Holy Wisdom MonasteryCare for the Earth, Friends of Wisdom Prairie, Phenology 2 Comments

By Sylvia Marek

Argiope spider

Yellow garden spider (Argiope aurantia), an orb weaver

Phenology is a science focused on observing and recording biological events from year to year and their relationships to the change of seasons and climate.

These are the “normal” phenology events we expect to see here and in the Madison area this month. We would love to hear about what you are seeing on the grounds of Holy Wisdom Monastery. Please comment on this post with what you are observing, where at Holy Wisdom and the date you observed the event.

August Phenology

I have kept records of August observations for many years. My entries for August follow. Some years the natural events occur a week or two early or later.

  • Thirteen and a half hours of daylight by the end of August
  • Migration of birds, monarchs, some dragonflies and salamanders
  • Increase in insect life and sounds
  • Profusion of flowers – goldenrods, sunflowers and asters dominate
  • Ragweed sheds pollen
  • Abundance of fruits and seeds
  • Mushrooms appear
  • Start of fall colors
  • Perseid meteor shower
  • Possible Northern lights


  • Goldfinch and cedar waxwing finish nesting
  • Most baby birds have fledged, adults molt and many start to form flocks
  • Few birds sing except for whisper songs and chip, chirp and tseet calls
  • Yellow warblers usually leave by early August
  • Fall warbler migration begins and continues all month as they journey farther south. Warblers arriving from the North include: Nashville, parula, redstart, chestnut-sided, black-and-white, Blackburnian, Tennessee, magnolia, Wilson’s, golden-wing and blue-wing, bay-breasted, common yellowthroat, Canada, black-throated green, blackpoll, Cape May and black-throated blue. These neotropical species migrate to Central and South America
  • Increase in hummingbird activity at feeders and flowers
  • Swallows gather on wires. Most leave by the end of August
  • Chimney swifts gather before migrating to South America in late August. Look for them at sunset as large flocks enter their roosting sites in chimneys
  • Bobolink flocks migrate to South America
  • Grackles and other blackbirds show up in flocks
  • Nighthawks migrate, mid to late August
  • Shorebirds continue to pass through (yellowlegs, least, semi-palmated, spotted and solitary sandpiper, short and long-billed dowitcher and others
  • Red-breasted nuthatches appear in August. Some spend the winter, others leave
  • Look for olive-sided flycatchers at the top of dead trees
  • Vireos, orioles and flycatchers begin to leave the area
  • Barred, great-horned and screech owls call and young owls continue to beg. They start hunting on their own


  • Deer antlers in full velvet
  • Fawns lose their spots
  • Squirrels and chipmunks continue gathering and storing nuts and fruits
  • Raccoons and fox feast on fruits


  • Insect activity and sounds are at their peak. Cicadas drone, bees buzz, short-horned grasshoppers produce mechanical and pitchless sounds, katydids rasp and crickets chirp, trill and “purr.” (I love the snowy and black-horned tree crickets)
  • Look for ladybugs, lacewings, aphids, ambush bugs, robber flies, tiger beetles and caterpillars
  • Treehoppers have interesting shapes and many are beautiful
  • Look on milkweed plants for large and small milkweed bugs (all are black and red-orange), several kinds of beetles and milkweed tiger moths
  • Golden tortoise beetles are found on plants in the morning glory family
  • Japanese beetles continue to devour plants
  • Winged ants disperse. Queens and small males take flight and mate. Queen starts new colony
  • Dragonflies dart and hover as they hunt for insects. Look for black-tipped darner, black saddlebag, white-faced meadowhawk, band-winged meadowhawk, yellow-legged meadowhawk and others
  • Green darner dragonfly and yellow-legged meadowhawk begin migrating south
  • Look for moths of all kinds at night, especially near lights
  • Butterflies commonly seen include Eastern tiger, black and giant swallowtail, Eastern-tailed blue, spring azure, fritillary, red-spotted purple, viceroy, wood nymph, pearl crescent, silver-spotted and least skipper, hackberry, American copper, clouded and alfalfa sulphur, cabbage white, hairstreak, and monarchs, of course
  • Monarchs – last generations emerge and nectar on flowers. They gather in the evening and roost on trees during the night. They start their fall migration to Mexico about the last week in August (Madison area)
  • Last sightings of twinkling fireflies and beautiful dogbane beetles
  • Mosquitoes, ticks, biting flies and chiggers continue to be active and annoying. Take precaution!


  • Some of my favorite spiders include:
  • Web makers
    • Yellow garden and banded argiope spiders make beautiful intricate webs. Look for their sparkling dew-covered orb-webs early in the morning
    • Look for the two-parted sheet web of the bowl-and-doily weaver
    • Filmy dome spiders create an inverted bowl-shaped web
  • Non-web makers
    • Jumping spiders can be seen in the daytime. They are small and very cute
    • Crab spiders are easy to observe during the day. They can change their body color to blend in with the flower they are sitting on… another cute spider!
    • Daddy longlegs or harvestmen are abundant now – they are not spiders!


  • Some start blooming in late July and some will continue blooming in September
  • White flowers: Marsh, flat-top, frost, heath and bog asters, creamy gentian, lady’s-tresses orchid, turtlehead, Culver’s-root, fleabane, wild quinine, flowering spurge, mountain mint, white prairie clover, rattlesnake master, New Jersey tea, bush clover, cowbane, water hemlock, pale Indian plantain, false boneset, boneset, whorled milkweed, Queen Anne’s lace, rattlesnake orchid pokeweed, white snakeroot, jumpseed, wild cucumber, white water lily, American lotus, arrowhead, and Indian hemp
  • Purple flowers: New England, stiff or flax-leaved, and silky asters; blazing star, cylindrical blazing star or dwarf and gayfeather, stiff gentian, bergamot, purple prairie clover, blue and hoary vervain, Canada tick-trefoil (clover), giant purple hyssop, ironweed, thistle, spotted and purple Joe-pye-weed, monkey-flower, wild petunia, swamp milkweed, purple coneflower, hedge-nettle Eurasian purple loosestrife (Lythrum salicaria) and native winged-purple loosestrife (Lythrum alatum)
  • Blue flowers: great lobelia, American bellflower, chicory, harebell, bottle, fringed and downy gentians, sky-blue and smooth asters
  • Red flowers: cardinal
  • Orange flowers: orange jewelweed
  • Pink flowers: tick-trefoil, soapwort, guara, nodding wild onion and smartweeds
  • Yellow flowers: sunflowers – naked stem, showy, woodland, saw-tooth and giant; goldenrods – early (Missouri), common, showy, stiff, elm-leaved, Riddell’s, grass-leaved, zigzag, dyer’s-weed or old-field; silphiums – prairie dock, compass-plant, cup-plant and rosinweed; ox-eye, yellow coneflower, brown-eyed Susan (Rudbeckia triloba), sweet black-eyed Susan (Rudbeckia subtomentosa), slender and evening primrose, St. John’s wort, false foxglove, yellow jewelweed, giant hyssop and wild parsnip

Grasses in bloom

  • Big bluestem, Indian, hairy grama, cord, switch, dropseed, side oats, little blue and panic grasses (witch and love)

Ripe fruits

  • Grapes, blackberries, blueberries, chokecherries, high bush cranberries, mulberries; gray, silky and pagoda dogwoods; bittersweet and sumac
  • Acorns fall
  • Walnuts are full size but green
  • Seeds are abundant


  • Fruiting bodies of mushrooms appear from August to frost. Look for inky caps, jack-o-lanterns, meadow puffballs, honey and oyster mushrooms


  • Salamanders migrate from ponds to woodlands during moist nights (usually in September)
  • Frogs and turtles are active
  • First fall colors appear. Leaves of sumac, Virginia creeper, poison ivy and red maple show touches of red. Basswood, butternut, walnut and locust leaves start to turn yellow

Sylvia Marek is a highly trained and experienced naturalist. She works for the University of Wisconsin Arboretum and is a first rate birder.

Please share the biological events you notice while at Holy Wisdom Monastery below (remember to include what you see, where and when).

Comments 2

  1. Thank you so much for the taking the incredible amount of time and effort to compose this so others may make use – it is so awesome! Knowing what to look for is such a huge benefit – it helped me and made my trail travels so much more interesting and enjoyable. This is an amazing tool, must have been a labor of love. Thank you so much 🙂

    1. Dear Mary,
      Thank you for your very kind comment. I am pleased that you are interested in phenology. I hope you are keeping your own records? May you continue to enjoy the beauty of the natural world.

      “The care of the Earth is our most ancient, most worthy—and after all—our most pleasing responsibility. To cherish what remains of it and to foster its renewal is our only hope.” Wendell Berry


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