Winter is tough on trees. The ground freezes so they can’t get a drink, and the winds zip around drying up what little moisture there is. Also, snow can be heavy. That’s why deciduous trees shed their leaves. We have all seen pictures on TV where trees that still have their leaves, fall and break during snow and ice storms. You seldom see any conifers with broken branches after a storm. The reason is the shape of the tree and the shape of their leaves. They have a better way of dealing with heavy snow.
Coniferous forests grow in areas with low winter temperatures and high snowfalls, like Minnesota. That being the case, they need a way to shed snow and hold on to water.
Conifers are conical. They have a single leader and their branches are spaced out in horizontal tiers. As the upper branches droop down with a snow load, they touch the tier below. Each subsequent tier supports the one above it, preventing the full load from breaking off branches. The tree assumes an umbrella shape so much of the snow just slides off and branches bounce right back.
Conifer leaves, needles, also have some unique skills to cope with our weather. The narrow shape doesn’t allow much transpiration, or water loss. With the soil frozen, the tree can’t pull moisture up so it needs to keep all that it has. The needles have a tough, weatherproof wax coating on them called the cuticle that reduces transpiration.
Coniferous forests typically grow in poor soils and dry conditions during the growing season. Deciduous trees have to produce a new set of leaves each spring so they need wetter conditions and better soil to grow and thrive. Conifers keep most of their leaves, a great energy saver. And, with our shorter growing season, they are ready to start photosynthesizing as soon as spring arrives, getting the jump on the leaf bearers.
The small evergreens we like to plant close to our homes can often get the whole roof full of snow as it falls off. Also, they are more apt to get “winter burn”, caused by strong, drying winds. A simple tripod of boards set over the smaller shrubs will protect them from snow dump. If they get winter burn – brown and dead on one side from the wind sailing around a house corner, give them a winter sweater. Just wrap a burlap bag, an old blanket or something similar around the shrub – not plastic. They will keep the dry wind off but may also heat up causing the tree to think it is spring and starting to grow. Not a good thing in January.
If you do get winter burn on your conifers, don’t be in a hurry to cut the affected branches off. They may recover. If the plant gets too ugly from constant winter weather and your attempts to repair it, dig it up and throw it on the compost pile. Lesson learned. A conifer won‘t do well in that location. Plant something else. House corners are death on most plants unless they have a windbreak. If your house’s corners are so ugly you need to cover them up, you have another problem altogether.
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