Falls leaves might look more vibrant this year.
That’s if the southwest metro receives warm, sunny days, accompanied by chilly nights in the coming weeks.
“Trees like those cool nights to concentrate the sugars in the leaves,” said Alan J. Branhagen, director of operations at the Minnesota Landscape Arboretum in Chanhassen. Branhagen supervises natural resources and plant curation and has kept a close eye on autumn leaves for a number of years.
While most of the state is covered in green leaves, in just a few weeks they are set to turn red, yellow and orange. The coloring may be better than the last two years, said Branhagen. Peak color in 2017 and 2018 was short, and overall leaf color was not very vibrant. This year, long-range weather forecasts are promising.
“The last two years have been less than stellar,” Branhagen said. “You need those bright sunny days, with few below freezing nights.”
Last year, there were several big storms that blew the leaves right off the trees at the Arboretum and the weather overall was too cloudy and drizzly for leaves to turn well. In 2017, it was too warm throughout October for the sugars to concentrate in the leaves — which creates the red, yellow and orange pigments before they fall off the tree.
Branhagen believes peak color may occur in early October.
The trees to look out for are the sugar and red maples, northern oak and white oak, he added.
“Those are some of our best,” Branhagen said. “I’m still holding up for the sugar maples to put on a show.”
The high amount of precipitation this year shouldn’t be an issue for most trees on higher ground. However, constant rainfall can cause leaf issues, he added.
For that reason, coloring along the Minnesota River, above flood stage for a long period of time, may not be spectacular.
“The trees really suffered down there,” Branhagen said, noting he has seen several along the banks that have died from too much water. The cottonwood trees, which have leaves that turn bright yellow before falling, likely won’t color well this year.
The best viewings of fall leaves will be in areas where the land is more hilly and naturally well-drained.
If residents have seen some trees in their neighborhoods turning color already, that might be a sign of a bigger issue, according to Branhagen.
Typically, trees that color earlier in residential areas suffer from being planted at an inadequate depth or were grown in pots and when they were transferred to the soil; the roots were never spread out — called girdling root.
The Arboretum is sure to have a variety of good coloring, Branhagen added. “The Arb has a diversity of trees — there’s sure to be something to be stunning.”
The Arboretum will also publish a weekly Fall Color Advisory, in which Branhagen will forecast the color of the trees for visitors, according to officials.
Those interested in seeing the fall leaves turn at the Arboretum can join Branhagen on a walk through the property at 2-4 p.m. Oct. 10. Participants will see the “Big Woods” maple collection and the Bailey Shrub Walk. The walk is $14 for members and $29 for non-members. The price includes Arboretum admission.
The Minnesota Department of Natural Resources has a Fall Color Finder, updated daily, showing users where trees are turning color across the state. For more information visit www.dnr.state.mn.us/fall_colors/index.html.
The best time to travel to see peak fall colors is mid-September to mid-October, according to the DNR’s website.