Colorado State Forest Service Offers Winterizing Tips for Urban Trees

When autumn arrives, homeowners often forget about their yards and focus instead on indoor tasks. However, urban trees and shrubs in Colorado require a regimen of fall care to remain healthy during the colder months.

“Once the leaves drop, most people don’t think about tree care until the first blossoms pop the following spring,” said North Area Community Forester Keith Wood of the Colorado State Forest Service. “But a little extra work now can generate big dividends next spring.”

Wood offers the following tips to prepare trees for winter:

  • Water trees appropriately. Trees on the Front Range may need more water than normal this fall because of an unusually dry September, but be sure to ease off before cold weather arrives. Continued heavy watering just prior to the first major freeze may cause tree damage, and drier conditions help trees go dormant.
  • Wrap the trunks of smaller trees. In Colorado, thin-barked trees like honeylocust, ash, maple and linden are susceptible to sunscald and frost cracks because of the drastic temperature fluctuations in fall and winter. To prevent bark damage, guard the trunks of younger trees up to the first branches using commercial tree wrap, which is available at most garden centers. Be sure to remove the wrap by early April to prevent the buildup of excess moisture.
  • Mulch. Apply 2 to 4 inches of mulch near the base of the tree, but not against it, to reduce soil evaporation, improve water absorption and insulate against the effects of temperature extremes on soil. Organic mulches, such as wood and bark chips or composted leaves, are best because they improve soil structure. Check with your community’s recycling program, as they often provide wood chips free of charge.
  • Hold off on pruning. Autumn sometimes is considered a good time to prune, but Wood says that pruning can stimulate trees to remain active. Instead, prune in very early spring when trees have not yet leafed and their branch structure is still visible.
  • Focus your efforts. Younger, more recently planted trees require the most care to minimize stress.

The Colorado State Forest Service recommends watering all urban trees and shrubs about once each month over the winter to combat the effects of Colorado’s arid climate. The best time for winter watering is on warmer days, during drier periods when snow has melted off and the temperature is above 40 degrees.

For more information about urban tree care, visit the Colorado State Forest Service website at or call (303) 438-9338.