September phenology

by Sylvia Marek

New England aster with rigid leaf goldenrod

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.

“The tint of autumn – mighty flower garden blossoming under the spell of an enchanter – frost.”
–John Greenleaf Whittier

September is a month of migrating birds, monarchs, dragonflies, bats, and
tiger salamanders. It is a month of bright yellow goldenrods and sunflowers; blue, purple, and white asters and gentians; and white lady’s-tresses orchids. Fall colors
parade across the landscape. Prairie grasses turn beautiful earthy colors and
display interesting and abundant seeds. Fruits and berries are colorful and provide
sustenance for birds and mammals. September, a month of misty mornings, sunny
days, sparkling frosty nights, and the big bright Harvest Moon.

The following are observations I have made over the years. Some events can occur
earlier or later, depending on a number of conditions and location of observation.

Birds

September is an exciting month to observe the annual fall migration of birds.
Breeding season is over and birds seem to be everywhere. Goldfinches, robins,
bluebirds, waxwings, doves, woodpeckers, and mixed flocks of warblers, vireos,
flycatchers, and thrushes gather to feast on insects, seeds, and fruits.
Most birds that nest in the far north or temperate zones and winter in the tropics
migrate at night when there is a north wind or it is calm. Listen for their sweet “seep,
cheep, chirp” call notes as they fly overhead.
I encourage you to go out early in the morning especially the day after a cold front
passes through and the wind is from the north.
Identification of birds in their winter plumage can be confusing especially
dull first-winter female warblers. It can be challenging but fun.
As many as 25-30 warbler species can be observed beginning in mid-August. They
peak in mid-September and continue into early October. Flocks of yellow-rumped,
palm, and a few orange-crowned warblers are often the last to leave. They will spend
the winter in the southern states.
Dark-eyed juncos, American tree sparrows, and brown creepers arrive in mid-late
They will remain here during the winter.
White-throated and white-crowned sparrows, pine siskins, golden-crowned and
ruby-crowned kinglets, purple finch, and red-breasted nuthatches arrive. Some
will stay throughout the winter.
Soaring birds migrate by day. Look for hawks, swallows, pelicans, and cranes.
Broad-winged hawks are one of the first hawk species to migrate.
Swallows and chimney swifts leave for the tropics during the day and are usually
gone by late September.
Nighthawks continue their journey to the tropics. Look for flocks passing over in
the early hours of evening.
Ruby-throated hummingbirds “fuel up” on flower nectar and insects before
heading south. I have seen them as late as October 9. Please keep your feeders up.
Shorebirds started passing through our area in July and usually reach their peak
in September.
Some ducks can be observed now. Lesser scaup, blue-wing teal, ring-necked duck,
red-breasted merganser, and northern pintail.
Barred, great horned, and screech owls are very vocal and give territorial calls.
Young owls leave their parents and look for new territories. This natal dispersal
is caused by a change in hormones.

Plants in Bloom

Periods of dry, hot, sunny weather or cool, cloudy, rainy days seem to affect when and
how long different plants bloom. Many of the following bloom in August and/or
September. Some bloom until there is a killing frost.

Woodlands, Savannas, and Edges

Goldenrods: elm-leaved and zig-zag.
Asters: calico, frost, Short’s, arrow-leaved, heart-leaved, New England, panicled,
flat-topped, large-leaved, and crooked stem.
Rudbeckias: brown-eyed Susan (R. triloba), black-eyed Susan (R. hirta), sweet
black-eyed Susan (R. subtomentosa), and cut-leaved coneflower (R. laciniata).
Woodland sunflower, white snakeroot, tall boneset, tall woodland thistle, evening
primrose, pale Indian-plantain, orange and yellow jewelweed, fleabane, burnweed,
white and hoary vervain, gaura, lady’s-tresses orchids, smartweeds, and the last
flowers of Joe-pye-weed, tall bellflower, jumpseed, figwort, and the hyssops.

Prairies

The prairie is bright with goldenrods, asters, sunflowers, Silphiums, gentians, thistles, lady’s-tresses orchids, and blazing stars (Liatris).

Yellow Flowers:

Goldenrods: There are about 22 different kinds of native goldenrods in Wisconsin.
The following are in bloom now on the prairie: Canada, stiff, showy, old field or
Dyer’s weed, Riddell’s, and grass-leaved. Goldenrods do not cause hayfever.
Goldenrod pollen is heavy and is a food source for insects. Ragweed pollen is
light and carried by the wind. It blooms at the same time as goldenrod and does
cause allergies.
Sunflowers have bright yellow rays (petals). Their disks (centers) are yellow, brown,
or brownish-purple. Look for saw-tooth, giant, woodland, naked stem, stiff,
and false sunflower (ox-eye).
The “Susans” or Rudbeckia’s include the very showy and aggressive native brown-
eyed Susan, sweet black-eyed Susan, black-eyed Susan, and cut-leaved coneflower.
Silphiums include prairie dock, compass plant, cup-plant, and the last flowers of
Tall Coreopsis (C .tripteris) and sneezeweed.

Purple, Lavender, and Blue Flowers:

Asters: There are about 23 kinds of native asters in Wisconsin and about 40 hybrids.
Asters have purple, lavender, blue, and sometimes pink rays. Their disks are usually
bright yellow until pollinated and then turn dark. Look for New England, smooth, sky-
blue, arrow-leaved, flax-leaved, silky, shining, heart-leaved, and aromatic.
Gentians: bottle, downy, and fringed are blue and stiff is purple.
Prairie or field thistle is in bloom and attracts goldfinches and myriad insects.
Rough blazing star (Liatris aspera) lights up the prairie with glowing purplish-
magenta flower spikes.
Look for spikes of great blue lobelia, purple hoary vervain and obedient plant.
Bright purple ironweed and pale purple monarda continue to bloom.

White and Pinkish-White Flowers:

The following asters have white rays and yellow disks: frost, panicled, crooked,
calico, and heath.
Large patches of pale Indian-plantain tower over the prairie. I love the “raindrops
on dusty soil” smell of the flowers.
Creamy gentians continue to bloom.
Biennial gaura or bee-blossom has dainty white flowers and pink buds.
Look for tall boneset, flowering spurge, whorled milkweed, lady’s- tresses orchids,
pearly everlasting, and cudweed.

Insects

Monarch migration continues to increase during the first part of the month. Look
for monarchs nectaring on flowers during the day. In the evening they gather in large
clusters and roost on trees during the night. They continue to head south to
Mexico where they will spend the winter.
Second broods of several butterfly species emerge. Look for black and the yellow
swallowtails, red admiral, painted lady, mourning cloak, cabbage white, silver-
spotted skipper, clouded and alfalfa sulphurs, and Eastern tailed blue.
Hummingbird and snowberry clearwing moths are beautiful. Often these small
sphinx moths feed on flowers at dusk.
Many butterfly and moth species spend the winter either as a caterpillar, egg, or
Several butterflies overwinter as adults.
Almost every year I have found the large caterpilllar of the Pandorus sphinx moth
on grape and woodbine. It is brown but can be green or orange with a row of
usually six white spots.
Woolly-bear caterpillars can be seen on the ground searching for a place to spend
the winter.
Green darner dragonflies (Anax junius) gather in large numbers before migrating
south for the winter.
Look for small red-bodied dragonflies or meadowhawks (Sympetrium sp.). The
autumn meadowhawk is probably the last dragonfly to be seen in fall.
Crickets, long-horned, and short-horned grasshoppers continue to call day and
night when temperatures are above 55 degrees.
Snowy tree crickets call day and night now. Count the number of chirps in 15
seconds and add 40 to find out the temperature.
Cicadas buzz during warm days and nights.
Increase in some species of hornets, wasps, and bees. Bald-faced hornets and
German yellow-jackets reach peak numbers.
Winged ants disperse. Queens set up new colonies.
Box elder bugs and Asian ladybugs (beetles) are very numerous now.
Goldenrods and asters provide pollen and nectar for many different kinds of
Look for butterflies, bees, wasps, flies, soldier beetles (leatherwings),
locust borer beetles, ambush and assassin bugs, aphids, ladybugs, lacewings,
leafhoppers and many more. To learn about pollinators and native plants read
“Pollinators of Native Plants” by Heather Holm.
Two-spotted treehoppers (Enchenopa binotata) can be found on nannyberry and
other shrubs. They are small, brown, and look like thorns. The female lays eggs
on a branch or twig and covers the eggs with a sticky white substance. The eggs
overwinter and hatch in spring.
Japanese beetle numbers start to decline.
Mosquitoes and biting flies continue to be annoying.

Arachnids

Deer or blacklegged ticks continue to seek blood meals.
Daddy longlegs or harvestmen are numerous now. They are not spiders. They
have only one body part.

Spiders

Web Makers:

The silky webs of orb weavers are beautiful especially when covered with
sparkling dew. Take time to watch a female weave her web and what she does
when she captures her prey.
Bowl-and-doily weavers create a two-parted sheet web near the ground.
Filmy dome spiders make an inverted bowl-shaped web on the ground.
Newly hatched spiders climb to the tops of vegetation and release a silver thread
of silk that is caught by the wind. Then the little spiderlings float through the
air to a new area. Look for these “ballooning” spiders.

Non-web Makers:

Jumping spiders are small, They have big eyes, short legs, and hunt during the day.
Tiny crab spiders can change their body color to blend in with the flower they are
sitting on. Crab spiders on goldenrods are usually yellow. Those on thistles are

Mammals

Male white-tailed deer begin to rub the velvet from their antlers and polish them
on tree trunks. Do not approach them now. They can be dangerous.
Deer molt their summer red coats and grow new thick gray or brown fur for winter.
Fawns lose their spots.
Chipmunks, squirrels, and mice gather and store nuts and seeds.
Muskrats prepare their dwellings for winter.
Woodchucks fatten up for their long winter sleep.
Rabbits seem to be everywhere.
Bats usually migrate by the end of September. There are eight native bat species in
Four migrate and four hibernate in caves or buildings.

Seeds and Colorful Fruits

Many flowers, grasses, and shrubs have finished blooming and produced an
abundance of seeds or fruits that are consumed by birds and mammals. White,
blue, purple, orange, and red fruits disappear quickly.
Seeds disperse in different ways.
Drifters and floaters—milkweed pods open and release brown seeds attached
to fluffy white “silk”. Thistle seeds are attached to fluffy “down” and float in the
Hitch-hikers—stick-tights, burs, hooks, barbs, and pods with tiny hooked hairs
catch rides on animals and humans. The seeds are found on tick-trefoil, beggar-
ticks, burdock, enchanter’s nightshade, agrimony, white avens, stickseed, and
sweet cicely.
Shooters—jumpseed and jewelweed.
Birds—deposit the seeds of berries and fruits.

Fall Color

Prairie grasses turn tan, golden-yellow, orange, reddish-pink, and bluish-purple.
Little bluestem turns reddish-pink to bronze-orange. Seeds are fluffy and
silvery-white.
Gaura and flowering spurge plants turn a beautiful orange-red color.
Although some leaves started to turn color in August, more turn during the month.
Red and orange: woodbine, poison-ivy, blackberry, sumac, viburnums,
and maples.
Yellow: walnut, basswood, ash, box elder, honey and black locust, aspen, and
sugar maple, and willow.
Brown: inner needles of white pine and Arborvitae.

Mushrooms

Most mushrooms (fruiting body of a fungus) can be found in August and September
until there is a killing frost. Look for them when there are alternating periods of
rain and dry weather. Few mushrooms are found during dry, hot weather. I have
found the following: Dryad’s saddle, russula, shaggy mane, meadow, bolete, oyster,
honey, puffball, bird’s-nest, fairy-ring, marasmius, sulphur polypore, chanterelle,
and more. Bright orange Jack-O-Lantern and bitter panellus glow in the dark.
Incidentally, white Indian Pipe is not considered a mushroom but rather a flowering
plant that parasitizes honey mushrooms.

Other

Spring peepers, chorus, and tree frogs occasionally call. They begin looking for
places to hibernate usually in wooded areas under leaf litter.
Galls can be found on most plants. The easiest to find are on Canada goldenrods.
Ball gall: a singe maggot spends the winter in it. In spring a small fruit fly emerges.
Elliptical or spindle-shaped gall: the egg of a gall moth overwinters.
Bunch gall: found at the tip. Small midge-like flies emerge before winter.
First day of autumn occurs on either September 22 or 23.

Storing September
“You ask me what I did today
I could pretend and say
“I don’t remember”
But no., I’ll tell you what I did today
I stored September.
Sat in the sun and let it sink in
Let all the warmth of it caress my skin.
When winter comes, my skin will still remember
The day I stored September.
And then, my eyes—
I filled them with the deepest, bluest skies
And all the traceries of wasps and butterflies.
When winter comes, my eyes will still remember
The day I stored September.
And there was cricket song to fill my ears!
And asters, like small clumps of sky…
You know how much I love them.
That’s what I did today
And I know why
Just simply for the love of it, I stored September.”
–Elizabeth Rooney. 9/25/90

September, a month to remember the scents, sounds, beauty, and peace you enjoyed and experienced as you walked the trails through the restored prairie, savanna, and woodlands of Holy Wisdom. A special place to remember in September.

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).