Winterizing Trees

December 14, 2017 GMT

If you didn’t have time for tree care this year, it’s not too late. Fall is the ideal time of the year to prepare woody plants for harsh weather ahead.

The winter dormancy of trees is dramatic and often misunderstood. A common myth is that trees shut down and essentially go to sleep for winter after leaf drop. In reality trees experience some of their most dramatic growth and vigor from September through December, most of it occurring invisibly below ground, but of critical importance to spring growth.

With dry winds, subzero temperatures and potential fluctuations of 50 degrees on any given day, trees face a harsh environment. Food reserves stored in twigs, branches and roots must be carefully conserved, as well as moisture, which is also consumed and necessary all winter long.


What can you do to help your trees through the Nebraska winter ahead of us?

*Identify your trees’ needs and potential health issues before problems arise and focus your time on the most useful activities.

* Consult. Know and understand your limits and consult with a certified arborist as needed, particularly for large, mature trees. Find arborists online from the Nebraska Arborists Association or the International Society of Arboriculture.

*Mulch around the base of trees with groundcovers or with 4 inches of organic wood chips. Extend to the edge of the dripline on smaller trees, and as far as feasible on larger trees. A circle of 6-8 feet is ideal for most. Do NOT pile mulch against the trunk, which can cause long-term damage and potential death.

*Remove or correct structural faults and dead wood, making smaller cuts to minimize wounding and exposure of heartwood. Prune damaged and declining twigs and branches to a healthy lateral branch.

*Aerate soils if they are compacted or poorly drained, but avoid damaging tree roots.

* Protect recently planted trees with immature bark with paper tree wrap, and use tree tubes or guards to protect them from mechanical and animal damage. (Rabbit and squirrel damage can be severe over winter so this protection can pay big dividends.)

*Water trees and shrubs during periods of low moisture, as is the case this fall. Trees less than 10 years old are particularly vulnerable. Water only when soil is not frozen and temperatures are above 40 degrees. You can use sprinklers, soaker hoses, spray wands or buckets with small holes drilled in the bottom to slowly disperse water. As a general rule, apply about 10 gallons of water per tree during dry periods, concentrating it under the drip line or canopy.

* Recycle leaves and yard debris into mulch or compost for healthy, nutrient-rich “living” soil. Using mulching mowers and adding moisture can help speed the breakdown.

Trees are important investments that provide enormous social, economic and environmental benefits. Investing in them in fall can yield large returns next spring.

-Eric Berg, Nebraska Forest Service