Though less spectacular than the color parade in the New England states, the Rocky Mountains and plains have their own fall foliage fling. Yellows dominate the color scheme, with aspens, cottonwoods and even yellowing larches (an evergreen) brightening the landscape.
On the eastern front of the northern Rockies and adjacent foothills and prairie, the first trees to undertake the transition from verdant green to yellow gold are the green ash. Native trees prized by no-fuss landscapers for their unmatched hardiness, green ash thrive from well-watered urban parks to shallow draws on the arid plains.
What accounts for their hardiness? I’m not an arborist, but I’m inclined to conclude that a certain amount of their toughness stems from their growing season. The first trees to lose their leaves and drift into dormancy, green ash are also the last to bud in the spring. This pattern seems to render them less susceptible to the bouts of extreme freezing and thawing that plague those trees who bud at the first sign of spring or hold their leaves well into October. The limbs of green ash remain leafless for a longer portion of the year than other deciduous trees, but this attribute also protects them from a permanently leafless condition in a climate sometimes cruel to trees.