Fall Color Report

See where fall color is showing in the tree and plant collections at The Morton Arboretum and visit throughout the season to see the colors change.

Fall color as of Wednesday, September 24

The tree-filled landscapes of The Morton Arboretum are displaying only the first few hints of fall color. Most of the tree collections and woodlands remain green.

In the Schulenberg Prairie (Parking Lot 25), grasses are maturing and turning to their fall colors of russet and gold. Scattered among them are a variety of blooming fall asters , mainly in shades of blue.

In stressful sites such as parking lots, some trees are showing early yellows and browns with a bit of very early leaf drop. These colors, which often are muted, may be seen on parking lot Freeman maples, Kentucky coffee-trees, tree lilacs, hackberries, Miyabe maples, and redbuds. The period of drought that preceded this week’s rain is also a factor in early leaf changes and muted colors.

Pine trees in the Conifer Collection and elsewhere are showing their normal fall needle drop. It is normal for pines’ third-year needles to turn yellow and then fall off.

In the Buckeye Collection near Parking Lot 6, many buckeyes have bare branches or brown or reddish-brown leaves. The late warm weather this summer has caused a few bottlebrush buckeye shrubs to open a scattering of some blooms for the second time this year. Corktrees, redbuds, honey-locusts, and hackberries are showing yellowing and dry leaves nearby.

In the Arboretum’s woodlands and landscapes, late-blooming flowers include goldenrod (yellow), Drummond’s aster (blue), and snakeroot (white). The leaves of plants along the ground are turning a paler green, but most branches overhead still are deep green. A few vines of Virginia creeper and poison-ivy have begun to turn red, though those vines in deep shade remain green. Sumacs and flowering dogwoods in sunny or drier sites have begun to turn red.

The aftermath of this summer’s cicada emergence can be seen on some trees where the tips of some branches are turning yellow or brown while the rest of the tree remains green. Those are branches where female insects laid their eggs.

The timing and vividness of the coming fall leaf color season will depend on the weather and rainfall in the next few weeks. After a long period of heat and dry weather in August and September, the soil is still very dry. Dry weather with warm nights typically results in paler, duller colors and earlier leaf drop. If the weather changes to bring cool nighttime temperatures, warm sunny days, and adequate moisture, it may allow the plants to develop brighter and longer-lasting colors.

Autumn is a season of change and every autumn is different. The Arboretum’s collections, woodlands, and landscapes always offer new experiences of color, sounds, and smells. Come outside and enjoy!

Fall color as of Wednesday, September 18

Hints of fall color can be seen in parts of The Morton Arboretum’s tree collections and woodlands. These changes are mainly the result of stress on trees from heat and dry weather this summer and fall.

Plants in the Arboretum’s parking lots have an especially stressful growing environment, and they reflect this by turning color earlier, with muted or dull colors. Look for early yellow and brown colors this week on parking lot Freeman maples, coffee-trees, tree lilacs, hackberries, and redbuds.

In the tree collections and landscapes, pines have started their normal fall changes, with third-year needles turning yellow and falling. Buckeyes near Parking Lot 6 are showing brown or reddish-brown leaves or bare branches from early leaf drop. Corktrees, redbuds, honey-locusts, and hackberries are also showing dry and yellowing leaves.

In the woodlands and landscapes at the Arboretum, flowers in bloom include goldenrod (yellow), Drummond’s aster (blue), and snakeroot (white). Trees overhead are still green, though some paler greens may be seen on the tops of the taller trees in exposed sites. A few vines of Virginia creeper and poison-ivy have begun to turn red, though in deep shade the vines remain green.

In the Schulenberg Prairie, grasses are maturing and beginning to turn gold and brown. A variety of asters add color highlights, mainly in shades of blue.

What the upcoming fall color season will bring depends on the weather. Currently, it is very dry and warm, which tends to result in less vivid tree color and earlier leaf drop. If there is sufficient rain and night time temperatures are cool and days are warm, this combination will allow the plants to develop brighter and longer-lasting colors.

Regardless, autumn is always a season of change, and our collections, woodlands, and landscapes offer a constantly changing experience of color, sounds, and smells. Come outside and enjoy!