By Terry Deem-Reilly, CSU Extension – Denver Extension Master Gardener since 2003
During mild weather, we relax and admire our gorgeous lilacs and viburnums, fertile fruits, and long-lived majestic street trees. With the coming of the colder months, however, we become aware that these lovely friends are susceptible to damage and even death from sleet, high winds, and heavy wet snow. The effects of this weather are a constant concern on the Front Range, but with a little forethought and planning, they can be mitigated (if never eliminated).
Effectively dealing with storm damage requires planning that begins when a gardener is considering installing trees and shrubs. (Minnesota Extension offers some great information on dealing with tree damage based on this principle.) However, as most readers of this blog are probably here seeking advice after a catastrophe, let’s do some time-traveling and begin with should be done (and not done) immediately following a storm and conclude with some hints for encouraging plant survival in advance of nasty weather.
This post features the highlights of emergency tree and shrub care; review the article ‘Caring for Storm-Damaged Trees’ from the Colorado State Forestry Service for more thorough guidance.
- During a heavy snowfall, brave the flakes to gently shake accumulated snow off tree and shrub branches with a broom. Lift each branch from the bottom instead of poking or shaking it. (Be prepared to do this more than once.)
- Before going out, look at the yard and street: are power lines down, are there dangling tree branches threatening to drop, or is debris or ice covering the turf or the walks? Any one of these can present a hazard to gardeners working outside. Above all, assume that any power line lying on the ground is live.
- Examine the damage: look for leaning, broken, or uprooted trees and shrubs. Determine if there are holes and cracks in bark, trunks, or roots. Note the state of the crown (branches and foliage) of each tree; loss of more than 50% of the crown may require tree removal.
- Leave ice coating the branches alone; it will melt as soon as temperatures rise above freezing.
- Damaged bark can be removed back to the point where healthy bark appears.
- Don’t top a damaged tree; you’ll render it weaker and more susceptible to disease.
- Avoid painting holes, wounds, or pruning cuts; the plants will seal and heal by themselves.
- Small tree branches can be removed by the gardener (see the fact sheet ‘Pruning Shade Trees’ linked below for details) but allow an arborist to remove large branches.
- Leaning shrubs and small trees can be moved back into position, staked, and mulched.
- Wait until new growth appears to fertilize.
- Inevitably, friendly visitors bearing chainsaws will appear, offering to repair your tree and shrub damage “for less than those big companies.” These are the horticultural equivalents of gypsy roofers who show up after hailstorms. They are usually untrained and not covered by workers’ compensation or liability insurance.
Now, let’s examine how we can minimize storm losses with some deterrence.
Mitigating plant damage begins with asking what genera, species, and varieties of trees and shrubs display less vulnerability and more resilience in the erratic Colorado climate. Luckily, the ready answer is (drum roll……) native and adaptive plants. Plants that have evolved in montane, submontane, or plains environments will rebound from weather damage much more quickly and thoroughly that those imported from dissimilar growing conditions. Plan for resilience by selecting trees and shrubs recommended in these resources:
- Native Shrubs for Colorado Landscapes
- Native Trees for Colorado Landscapes
- Front Range Tree Recommendation List
- Tree Selection: Right Plant, Right Place
- Plant Select
Once plants have been selected, practice proper siting and planting. Again, we’re assisted by Extension and Plant Talk resources:
Proper cultivation and integrated pest management (IPM) are indispensable to plant health, as outlined in these publications:
For information on specific plants, diseases, and pests, review the resources on subjects from “abnormal and distorted plant growth” to “Zimmerman pine moth” included in the Extension page Online Gardening Publications (Trees and Shrubs).
Fans of Gardener’s Supply Company should check out the great discussion of winter damage prevention on their website.
We hope that this is helpful in the present emergency and beyond – but, as always, Denver County Extension is eager to help with all problems and concerns!
