Winter tree care - How to look after them in winter
The storms, ice and rapid temperature fluctuations, above and below zero, are characteristic of winter weather and it takes its toll on trees across the UK. Even for species native to colder regions, this can be a stressful time. This is particularly true for the exposed and isolated trees of the residential landscape. However, some of this stress is unavoidable. The average tree owner has little control over the climate but there are things that you can do to minimize the damage caused by the stresses of the winter months.
Cold stresses take a number of forms. The first is the effect on mature trees of a rapid change between daytime heat and nighttime freezing. These temperature variations can lead to stresses inside the tree between the outer bark and inner wood leading to cracks called frost cracking (this is the side receiving the most winter sunlight). There isn't much that can be done to prevent frost cracking.
In many cases, the tree is able to repair itself although the cracked area remains vulnerable and subsequent cracking at the same place can cause major damage. In the case of young trees and trees such as palms and other tropicals, the tree owner might consider wrapping the bark as part of the autumn maintenance procedure.
Another cold stress is the impact of sudden early frosts on late growth. Late season tree growth is vulnerable because it doesn't have the same time as established growth to prepare for cold. Ice crystals can rupture the cell walls on the new tips of branches causing them to die off. To avoid this, you should avoid pruning until after the tree has gone into dormancy in late autumn. If you prune too soon, it can encourage new growth and increase the risk of frost damage. Also, avoid using fertilizers with high amounts of quick-release nitrogen, which is more suited to the growing spell in summer.
At times during the winter, particularly for evergreens, drying out can be a real problem. Winter drought occurs when a tree loses more water than it can absorb from frozen ground and is especially acute during the early spring when the ground remains frozen while the spring sun begins warming the rest of the tree. Windy conditions can also add to the problem Whilst there is no sure-fire solution to winter drought, you may be able to control the problem by laying down a thick layer of organic mulch around the base of the tree in late autumn before the onset of winter. The mulch can help to slow moisture loss and runoff while acting as a temperature buffer for the roots, thus giving them added protection
Branches are more vulnerable to breakage during the winter months. This is especially the case for deciduous trees - The wood can harden and become brittle and therefore susceptible to wind damage. Ice and snow accumulation which affects both deciduous trees and evergreens alike can also be an issue. The key to minimizing branch breakage lies, once again, in good autumn maintenance, especially pruning. Pruning weak and vulnerable branches and removing one limb of a pair (V shaped crotches) can make the entire tree less susceptible. It's also worth considering covering the entire tree with a hardy tent-like housing. For larger evergreens, you can also tie up and reinforce branches.
When buying new trees, choose only those species native to your area's hardiness zone. Trees native to areas even one zone milder than yours might experience significant stresses during your region's winter months.
- Maintain good tree upkeep throughout the year. Strong healthy trees will always have an easier time than weak and damaged ones.
- Do a post spring inspection of your trees every year. Promptly treat any damage that you find.
- In preparing for winter, remember to prune only after your trees have entered dormancy after the risk of new growth.
- Apply a good autumnal fertilizer that promotes root growth and not leaf growth.
- Lay a layer of mulch down around the bases of your trees to moderate temperature fluctuations and moisture loss. Leave a space between the mulch and the trunk of the tree to discourage mice, which can damage the tree.
- Check occasionally during the cold season for signs of rodent damage
The original article can be found here - Treehelp.com