This time of the year, you might be well-served to avoid Colleen Gregoire on the highway. Her attention may be elsewhere.

“I practically drive off the road looking at the good vistas,” Gregoire says.

You’ll have to forgive her. She’d rather be sitting outside painting.

Like many Lawrence artists, Gregoire is inspired by the yellows, reds and oranges that form a bright palette in the trees during the autumn.

“My painting is definitely affected by the seasons,” Gregoire says. “It’s something I’ve always enjoyed in my personal life. Growing up in this part of the country, I’ve always enjoyed the seasonal changes.”

With peak leaf-viewing season 10 to 17 days away, conditions are favorable for a bright fall, says Craig Martin, professor and chairman of biological sciences at Kansas University.

Kansas University Facilities and Operations workers, from left, Derek Peterson, Jim Crumpton and Bernard Herman, pile up leaves with blowers in front of Budig Hall on KU's campus. The crew made its way around campus last fall, hauling off leaves that began to fall in recent days.

The change in color, caused by cooler temperatures and shorter days, signals trees shutting down photosynthesis, their energy-making process, for the winter months. The peak day for fall colors ranges from Oct. 15 to Oct. 22, Martin says.

As chlorophyll, the chemical responsible for photosynthesis, exits the leaves, the underlying yellow pigment in some leaves is exposed.

Other trees make red pigment to replace the green chlorophyll. Those trees make more red pigment when it’s dry in the fall, and when the days are warm and sunny and the nights are cool but not freezing.

Trees that produce orange leaves have a smaller amount of the red pigment, which mixes with the yellow.

“The yellow pigment is always there, so it’s always a good year for yellows,” Martin says. “Definitely there are good years for reds, terrible years for reds and everything in between. We’re having warm, sunny days and cool nights. If it doesn’t rain much, it could be fabulous.”

Falling for leaves

Lawrence artist Paul Hotvedt has a simple reason why so many artists pick up their brush, camera, pencils or other tools and head toward their favorite trees.

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He says it’s because the artists have something new to look at.

“After several months of seeing a predominately green landscape, we experience the visual thrill, and relief, of seeing the complementary reds and oranges in the autumn foliage,” he says.

That’s partly why Gregoire will head out to do oil paintings later this month. For her, a key is not overdoing the bright colors she sees in the leaves.

“It’s about color and balance of color,” she says. “I like to deal with a lot of spatial depth in my painting. I transition from brighter colors to duller colors to give that spatial depth.”

Outdoor photographer Kyle Gerstner will be heading out with his camera soon, too.

“In the East, it’s more about trying to get the ultimate fall shot,” he says. “Here in Kansas, it’s tougher. The fall colors are more subtle.”

He tries to get detail shots of leaves on overcast days, especially after it’s rained, to capture more saturated colors. He uses a polarizing filter to cut down glare to make the leaves stand out even more.

While some photographers aim for the quintessential postcard-like scenes featuring church steeples with fall leaves or other manmade-nature mixes, Gerstner prefers to keep it all about the trees.

“It’s a little harder to come by,” Gerstner says. “But I always like the challenge.”

Festive colors

In Baldwin, residents have turned love of leaves into a celebration. Since 1958, the third weekend of October has been reserved for the Maple Leaf Festival.

Local lore says a train once dropped off 100 maple trees there that weren’t addressed to anyone. Residents decided to plant them.

But Roger Boyd, a semi-retired Baker University biology professor and son of two of the festival’s co-founders, sees two trends that he worries will alter leaf-viewing in Baldwin and the area for future generations.

First, nurseries aren’t selling many of the sugar maples that have traditionally brightened up Baldwin each fall. Instead, they’re opting for red maples.

A perfect autumnal corroded leaf, displaying a range of warm tones. Over white. Makes a great Photoshop alpha channel/layer mask when desaturated.

The red maples, which he says don’t turn red as consistently as the sugar variety, are heartier early in their lives. That means there’s less chance amateur arborists will ask for refunds if the young trees die. However, red maples are more susceptible to heat and drought than sugar maples when they get older, he says.

The second trend isn’t something Boyd or Baldwin residents can do much about.

“What we’re seeing, in my belief, is related to global warming,” Boyd says, explaining that the weather is staying warmer later into the fall. “The trees are turning a little later every year, from four to eight days difference from what it used to be.”

That might mean that, down the road, the Maple Leaf Festival will need to be pushed back a week.

If you’re impatient for the changing leaves, Martin, the KU professor, has another suggestion: the often-overlooked fall colors in the Kansas tallgrasses.

“There’s a variation and richness of subtle colors in the native prairies,” he said. “We always focus on maples, but if you drive between here and Topeka along Stull Road, there are nice native prairies that have the richest golds and coppers – more metallic colors. It’s more of a subtle Kansas beauty.”