Great things may come to those who wait, so it’s not necessarily a good sign that trees aren’t waiting as late as usual to turn colors in the Coulee Region.
With fingers crossed that the bursts of reds from sumacs are not harbingers of an early and evil winter, two local experts said Monday that the recent lack of rain probably will mean a fall more drab than the colorful palette of the past few years.
The initial Fall Color Report and map from Travel Wisconsin.com reflects some early color shows, logging La Crosse County at 25 percent turned and predicting a peak during the third week of October. Vernon County south of La Crosse is at 35 percent and expected to peak next week, while the Kickapoo Valley Reserve in eastern Vernon is already at 45 percent and also on schedule to peak next week.
The Minnesota Department of Natural Resources was beside itself with excitement in the forecast that accompanied the launch of its map last week, predicting a splendid show, largely because of the copious amounts of rain during the summer. The potential flaw could be that it didn’t factor in several recent weeks of dry weather.
Western Wisconsin also experienced a wet summer that usually bodes well for a colorful fall, but the rainfall lapse probably will lead to muted colors, said Dorothy Lenard, a natural sciences administrator at Viterbo University in La Crosse who also has a substantial forestry background.
“I’ve noticed leaves are turning much earlier than the past few years,” partly because trees haven’t had as much water and cool nights to sustain growth, said Lenard, who observed the phenomenon during her annual trip to the Vernon County Fair in Viroqua.
Although Lenard said she enjoyed seeing colors, she said trees along the route normally are greener this time of year.
“It’s not as pretty, and a lot more leaves are coming down,” she said. “I think we’ll have a quicker fall, and leaves won’t stay on as long.”
Sumac trees are turning their brilliant reds earlier than normal, Lenard said, an observation echoed by University of Wisconsin-La Crosse biology professor Tim Berger.
Of course, both Lenard and Berger said the most important trigger is diminishing daylight; as the days grow shorter, trees have less sunshine to use during photosynthesis to help make the sugar-like nourishment that fuels growth. Lacking that, trees’ chlorophyll also disappears, allowing the colors to emerge.
Asked how trees in the Kickapoo Valley Reserve already could be halfway turned, Lenard and Berger said trees along ridges are more stressed than those in valleys because they have less access to water.
Minnesota’s color map shows much more color-changing activity this year than during the past two. Of course, a brisk windstorm and/or heavy rain can make predictions moot, Berger said.
Unseasonably warm temperatures, such as those during this past weekend and expected again next weekend, also creates stress that wreaks havoc with trees, especially when it remains dry, he said.
A light frost can speed the color change, while a hard frost probably will bring it to a halt.
In the city of La Crosse, the recent dryness created stress on trees, prompting forestry officials to advise homeowners to water trees generously in preparation for winter. Watering is especially important along boulevards, where the trees will be exposed to salt baths applied to melt ice during the winter and need to be healthy to survive.
Some changes are species-specific, Gerber said, which explains why sumacs are changing: that is their normal pattern. Some sugar maples have started, while silver maples are later turners, Gerber said.
“Everything is getting ready for winter a little early,” Lenard said.
That might boost the spirits of outdoor sports fans, such as skiers and snowmobilers — as long as the winter has more snow than the past two years, which have been bleak for skiers and downright miserable for the sledders.