Maryland’s drought may cause trees to shed leaves sooner than normal, but those that keep their foliage should produce their usual cornucopia of colors this fall.
“The trees will go dormant earlier than they normally would have if we had not had the drought,” said Steven W. Koehn, director and state forester of Maryland’s Department of Natural Resources Forest Service. “They are trying to conserve moisture, and one of the ways to conserve moisture is to drop your leaves.”
Premature loss of leaves in parts of a tree before it turns color could have some impact on the display, Koehn said.
Trees that grow close to water, such as yellow poplars, sycamores and ashes, are more likely to lose leaves prematurely, he said. Mountain species, such as oaks, hickories and some maples, are more tolerant of the dryness and will be less affected.
Trees react to drought in a number of ways, Koehn said: early leaf drop, prolific seed production and, a bonus for tree-gazers, a possible deepening of color.
“The increase in concentration of sugar production (caused by loss of moisture). . . can in some species make the color more vibrant,” he said.
Leaves that turn red in the fall can actually produce deeper, more brilliant hues in dry weather – in the right conditions, said Bassam Shakhashiri, a chemistry professor at the University of Wisconsin and a graduate of the University of Maryland.
“There are so many things that could happen,” he cautioned. “You could get a hail storm and that would tear off all the leaves,” even if the colors are at their peak.
Leaves begin to turn when autumn climate changes cause them to slow their production of chlorophyll, the pigment that makes them green. During warmer months, chlorophyll masks the foliage’s inherent red and yellow pigments. But as the days shorten and the nights grow cooler, trees stop producing the green pigment, allowing the other colors to flare into display.
Maryland’s peak viewing season almost always begins in mid-October, although it can begin earlier in the mountains and later in the east, said Bob Webster, western region forester with the Department of Natural Resources. Sumacs and black gum trees are among the first to change, turning crimson early on. Red maples are found all over the state, but sugar maples, which provide reds as well as oranges and yellows, thrive mostly in the mountain regions.
Garrett and Allegany Counties will give the best color views at the peak time, Webster said.
“The trees that are in Garrett County are very similar to a lot of New England forests,” he said, describing the evergreen spruce and pine trees that provide a green backdrop for the changing colors. “That’s probably why the leaves are good there.”
State parks in western Maryland, such as Savage River State Park, and in Central Maryland, Catoctin Mountain Park, will provide brilliant scenery during peak times, Webster said.
Ultimately, however, meteorologists say the drought’s effects are damaging for trees.
Forest fire danger, in particular, may be high, Koehn said, with the accumulation of fallen leaves from the early leaf drop.
“I’d rather see the red fall color of the foliage,” he said, “than the red of a forest fire.” – 30 – CNS-9-20-02