Fall foliage on track, but slow to peak

COLUMBIA — Unseasonably warm nights have helped see this year's fall foliage off to a slow start.

Ann Koenig, an urban forester for the Missouri Department of Conservation in Columbia, said the absence of sunny days and cold nights has led to the delayed fall foliage in the central part of the state.

 "Bright days and cool nights contribute to bright color," Koenig said.

As a result of the delay, Koenig is uncertain if this season's fall foliage will be as spectacular as initially expected.

"I don't know," Koenig said on Wednesday. "The later it gets in the season, the more likely it will be that we get a freeze, which will cease our nice fall color display."

There's rain in the forecast through Friday, and any heavy rain or gusty winds could blow leaves off their branches, disrupting their color cycle.

"If you're wanting to see good fall color, you don't want high winds right now or a hard freeze," Koenig said.

Typically, the peak of fall foliage comes during the second or third week of October, but sometimes it doesn't come until the last week of the month. The peak  for every species of trees is different, however, and fall color tends to show up in waves rather than a single peak.

Steve Pallardy, MU forestry professor, agreed with Koenig that weather is the driving force behind fall foliage. He offered up another reason why some people are wondering why this season seems so lackluster.

At this point in the fall, oak trees — one of mid-Missouri's most prevalent species — have been slow to change color.

"The oaks really aren't that far along," Pallardy said Tuesday. "Most of our forests are oak."

The oaks are often the season's late-bloomers. Based upon the date stamp on some of his photographs, Pallardy said, oaks didn't peak last fall until early November .

According to the Missouri Department of Conservation's Fall Color Update released Friday for Missouri's central region, some oaks have begun to slowly change color, and many can be found with a branch or two of color amidst an otherwise green tree.

While the oaks may be slowly changing, most of the other common tree species are well into their yearly cycle:

• Black walnut: The black walnut's yellow leaves have come and are almost gone. Presently, the walnut's most distinctive feature is the presence of its green balls of fruit amid its branches.
•  Ash: According to Koenig, ash trees — sporting either hues of yellow or purple — have dropped about 70 percent of their leaves.
• Dogwood: Most dogwood leaves are hiding their vibrant red color in the understory of the forest. Dogwood leaves are close to their peak, Koenig said.
• Sassafrass: The sassafrass, touting bright orange leaves that stick out well along the forest canopy, are peaking now, Koenig said.
• Hard (sugar) maple:  Maples are beginning to show their orange-red leaves.

"We've seen some in really nice colors," Koenig said. As far as a peak, Koenig added, some maples are "sporadic in their timing" and often vary tree by tree.