State College, PA - Centre County - Central Pennsylvania - Home of Penn State University

Pennsylvania Fall Foliage Outlook Is Bright, Experts Say

by on September 13, 2017 5:00 AM

A rainy and relatively cool spring and summer will make for colorful fall foliage in Pennsylvania, according to Penn State forest experts.

"The cool, moist summer should usher in great fall colors," Marc Abrams, professor of forest ecology and physiology, said in a news release. "The robust physiology of the trees this year should predispose them to producing good color."

Kim Steiner, professor of forest biology and director of the Arboretum at Penn State, said it's a good sign for fans of fall foliage that, unlike in recent years, leaves have largely not begun to turn already.

That often happens after a dry August, particularly on walnut and red maple trees, Steiner said.

Abrams explained that as temperatures begin to fall, trees stop producing chlorophyll, the green pigment responsible for photosynthesis, and in the process other leaf pigments -- xanthophylls and carotenes -- are revealed to show yellows and oranges in some tree leaves. And as chlorophyll production stops, trees produce another pigment, anthocyanin, which creates the reds and purples seen in other tree leaves.

"One thing that I have been impressed with in my 30 years of gauging foliage is the resiliency of the display," Abrams said. "Year after year, despite the conditions, there are places where the trees show good color, but perhaps not great color every year. However, this year, the trees should be in great shape to show off their best colors."

Steiner added that the loss of white ash trees is beginning to become more noticeable. A invasive beetle, the emerald ash borer, has killed off most of the native white ash trees in central Pennsylvania.

"This species was never a dominant component of our forests," Steiner said. "But its yellow to purple fall color was a wonderful accent in the landscape and now will be largely gone."

Abrams said that while summer conditions have been ideal for colorful foliage, colder temperatures will need to arrive by mid-October for the best display.

"Unless things go haywire with the weather -- with unusually warm and wet conditions -- it should be a fine year," he said. "We believe that clear, bright days, low but not freezing temperatures, and dry but not drought conditions promote the best fall colors."

Next Article
Second-Half Surge Powers No. 2 Penn State Field Hockey Past Bucknell
September 12, 2017 9:36 PM
by Mikey Mandarino
Second-Half Surge Powers No. 2 Penn State Field Hockey Past Bucknell
Disclaimer: Copyright © 2018 All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

order food online