Journal for September 30, 2026

We’ve been enjoying the green in the leaves and on the hillsides.

Now the leaves are starting to turn color. Red Maples are some of the first to change.

Prickly Ash has especially beautiful gradations – from green to yellow to red.

Monarch on Frost Aster on September 16

The Monarch migration has been moving through – with larger numbers than we’ve seen in the last few years. Our biggest count was 226 on one afternoon walk. Now the peak of the migration has moved farther south, and we’re just seeing a few stragglers.

September 28 – Male Monarch on New England Aster

Karen Oberhauser, who studies Monarchs, says that these late ones have a harder time making it all the way to Mexico.

Mike has been working on and updating the chart where we record the numbers of Monarchs we see. He’s added weather data and made it more interactive. Click on it to see the explanation of how we get the numbers, and ways to explore the chart.

As the days and nights get cooler, it’s becoming much more comfortable to work outside.

Mike has started the fall mowing. One of our planted prairies has an aspen problem – mature aspens grow on the neighboring land and they send up thousands of sprouts in our prairie. That prairie is the favorite stopping place for migrating monarchs, so we wait until the migration has moved through, and then Mike mows the sprouts. It doesn’t get rid of them – they grow back the next summer – but it keeps them from becoming a forest.

He tries to leave as many unmowed spots as he can – places that have few aspen sprouts – as refugia for insects and small animals.

This is what the clumps of dense aspen sprouts look like after growing for just one summer.

I’ve discovered that if I cut and treat the stem of an aspen sprout with herbicide, it doesn’t grow back. But I have to cut and treat each one. I’ve been working on this in a wide strip along our walking path for about the last 5 years. It’s rewarding to see aspens disappear, but it’s a slow process and, since the prairie covers about 14 acres and there are thousands of sprouts, doing them all will take years. This is part of the strip that I’ve worked on, with the mowed area beyond it.

One of the rewards of working so close to the ground is that I see things I would normally miss. Recently I’ve been finding orchids – Purple Twayblades – growing in patches down among all the prairie plants. It’s not a species I planted – orchids are generally difficult to grow. I wonder how long the plants have been there – maybe since before the prairie was a crop field.

Purple Twayblade leaves

In late summer and fall, the wetland is full of flowers.

Wetland sunflowers and Goldenrod

My two favorite wetland flowers both bloom in the fall….

American Grass of Parnassus is not really a grass, but its wide leaves are at the base of the plant, and its slender flower stalk lets it blend in with the surrounding grasses.

Fringed Gentian

This is the wet end of East Center Valley. It looks beautiful when the flowers are blooming, and even lovely when they’re topped with fluffy seeds.

One Swamp Thistle is still in bloom.

The Swamp Thistle with a bumble bee

Pine Point with Big View Prairie at the top, and Canada/Tall Goldenrod in the wetland

Another fall yellow – Golden Aurivella – growing in the Glen

We’ve seen quite a few Painted Ladies in the last few weeks. Painted Ladies are found on all the continents except Antarctica and South America. They migrate erratically, and their movements aren’t well understood. iNaturalist has a long article about some of the work that’s being done to figure them out, and about some individuals that were recently found in South America.

Painted Lady underside

Round-headed Bush Clover – a common, but not showy prairie plant. It’s most obvious in winter, when the dark seed heads mix with the prairie grasses. Eastern Tailed-blue butterfly caterpillars eat its flowers and seed heads.

Stiff Goldenrod with many insects – flies, wasps, a Common Buckeye and a very worn Great Spangled Fritillary.

Showy Goldenrod is one of the last flowers to bloom in the fall. It’s a favorite nectaring plant for late butterflies – including Monarchs – and for many bees.

I was driving up to work on top one morning when a Barred Owl flew across the trail into a tree. It stayed very well hidden and watched me though the leaves until I drove on.