Maine’s famous fall color is a bit behind schedule this year, but the heavy rain saturating the state this week may mean brighter reds, oranges and yellows when the leaves finally turn, according to Gale Ross, coordinator of Maine’s fall foliage reports.
“It’s hard to make a prediction,” Ross said. “But I believe the rain will help the color substantially.”
Ross has been in charge of Maine’s official fall foliage website, mainefoliage.com, for the past 10 years. A service of the Maine Department of Agriculture, Conservation and Forestry, the website provides the public with weekly fall foliage reports from observations by Maine Forest Service and state park rangers throughout the state.
“We’re going into our fourth week of reporting, and we’re only between 15 and 20 percent color because our weather plays such a significant role,” Ross said. “We haven’t had rain, and we’ve had a really warm September, with warm days and nights. We really need cooler nighttime temperatures without a killing frost to move the season along.
“Right now, we’re tracking about a week behind, which means for Maine that we’ll go into a longer foliage season,” Ross said. “We could go into late October, provided we don’t get a killing frost and substantial rainfall when the leaves reach their peak, which would knock them all down.”
Maine’s weekly fall foliage reports date to 1959, when Forest Commissioner Austin Wilkins first asked Maine Forest Service rangers to report the amount of color change and leaf drop in their regions on a weekly basis from mid-September through mid-October. These reports were radioed to the forestry headquarters in Augusta, then mailed or phoned to Maine news agencies.
Reporting fall foliage conditions throughout the state fit with the forest service’s mission to provide the public with accurate, relevant and timely information about the state’s forest resource.
In 1996, the foliage reports moved to the Maine state government website, distinguishing Maine as the first state to post weekly foliage conditions on the Internet. In just one year, the Maine Fall Foliage website expanded to include a regional map showing peak fall foliage progression, as well as photos of fall foliage posted by the Maine Forest Service and park rangers throughout the state.
Over the years, the website has continued to expand. This season, it features a “frequently asked questions” section, facts about Maine’s 17 million acres of forest, and links to relevant forestry and tourism resources.
More than 8.6 million people visited Maine during the fall season in 2014, according to the Maine Office of Tourism, out of a total annual visitation of nearly 33 million. These fall visitors spent more than $1.6 billion out of an annual total of direct tourism expenditures of about $5.5 billion.
“There’s always a desire to get people out past the coast, to expand where they go,” said John Bott, spokesman for the Maine Department of Agriculture, Conservation and Forestry. “I think the foliage season is one thing that helps us do that. It encourages people to visit all regions of Maine.”
The science behind the colors
We see it happen every year — the forest slowly transforming from a sea of green to a patchwork of golds, oranges, reds and browns.
“This year, we’re tracking a bit late,” Ross said. “But obviously it’s still going to happen — that’s Mother Nature’s way of putting the trees to bed for winter.”
To survive the winter, many trees and other plants in Maine have to shed their leaves and seal up their branches so they won’t lose moisture during the dry, frozen months ahead. But why the display of color?
“We’re looking at what’s been hidden all season long,” said Kate Garland, horticulturist with the University of Maine Cooperative Extension. “It has just been masked by the green chlorophyll.”
All summer, chlorophyll in leaves absorbs energy from the sun and uses it to produce sugars and starches to help the tree grow. But in addition to green chlorophyll, leaves contain yellow and orange pigments, such as xanthophyll and carotene — these colors are just hidden during the summer, according to a bulletin about leaf color published by the University of Maine Cooperative Extension.
In the fall in Maine, leaves stop producing chlorophyll. That’s when the yellows and oranges become visible.
“It’s a hard thing to wrap your brain around,” said Garland.
But that’s not all. In some species of trees, anthocyanins are formed, giving leaves red, purple or bluish hues.
“Different species tend to have different types of pigment, but within that, different individuals will have different pigmentation,” Garland said. “Even if you have two sugar maples side by side, different parent plants will have different genetics and slightly different pigments will show.”
Some trees, such as silver maple, aspen, birch and hickory, only show shades of yellow, according to the UMaine Cooperative Extension bulletin. Red or crimson leaves often are produced by trees such as red and sugar maple, flowering dogwood, black gum and red oak.
“My favorite tree in the fall is the tamarack — also called the hackmatack or larch — they turn a bright golden color that’s gorgeous,” Garland said. “That’s an interesting tree because it’s a conifer that loses its leaves every year. Typically you think of conifers as evergreens.”
In general, warm sunny days, combined with nighttime temperatures below 45 degrees but above freezing, result in brighter pigmentation in trees and raise the level of red coloration, according to the bulletin.
“All sorts of factors play into it,” said Garland. “It’s a really dynamic thing to understand, but it’s also really fascinating.”