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Winter Injury to Trees and Shrubs in Frederick


Winter Desiccation:

Because of the prolonged and climatic conditions this winter we are already starting to see many signs of winter injury on Trees and Shrubs.

Winter Desiccation will probably be the most common damage we will see this spring. Desiccation occurs when the water leaves the plants faster than it is taken up. During severely cold periods the ground may freeze to a depth below the extent of the root system, which cuts off the supply of the water. Although the damage mostly occurs on evergreens, it can damage deciduous plants also. The actual severity of the damage can vary greatly depending on many factors such as plant variety, location, wind and sun exposure.

The least severe damage caused by desiccation is generally referred to as Winterburn. This is the browning or scorched leaf tips on evergreen foliage. Browning usually occurs from the needle/leaf tip downward. In mild cases when the branches or woody tissue has not been damaged, new growth will push out the damaged leaves/needles. Typically after the spring flush of new growth, the plant will recover.

In severe cases with damage to the branches, the dead parts of the plant will have to be removed. In some situations, removal of the plant is the best option.

There are several things that can be done to help reduce the risk of winter desiccation to your plants.

  • Select hardy plants from the start. Avoid planting out of their hardiness zone.
  • If we have a dry fall, give your plants a good watering before winter.
  • Make sure all plants have at least 2 inches of mulch around them.
  • If you have certain plants that are more susceptible to desiccation, put up temporary wind blocks.
  • Keep your plants will fertilized.
  • An Anti-desiccant can be sprayed to prevent water loss. More than one application will be necessary to achieve winter long protection.

If you are seeing signs of winter desiccation on your plants now, we would recommend waiting to see how severe the damage is before doing anything. If the leaves/needles are just burned, you will see signs of new growth emerging from the branches. If the is the case let Mother Nature take her course. If you didn’t fertilize your plants in the fall, you should fertilize them now. If you are not seeing any new growth on the branches and the branches are dried out and break easily, you will have to prune the dead plant material back until you hit green live tissue. Again if you didn’t fertilize in the fall, do so now. If the plant is severely damaged and you think it will take a long time to recover and/or it will be a continuing problem, removal may be your best option.

Snow and Ice Breakage:

Heavy snow and ice storms can cause damage to branches by bending and breaking them. Multi-stemmed plants are most prone to damage. Many hardwoods, especially maples and Bradford pears, are susceptible to breakage. Properly pruned trees will reduce the risk of injury. If the snow and ice has less area to collect, it will reduce the weight of the snow and ice.

Girdling by Animals:

Another common problem is girdling from mice and rabbits from their feeding on the bark of the plants. Usually the damage occurs in long periods of snow cover when the food supplies get low. To prevent damage, maintain a weed and grass area at least 2 feet in radius around your plants. You can also wrap the trunks or branches with wire mesh. Make sure it goes below ground level and up to 2-3 feet in height. The mesh should be removed in the spring. If your plant has been completely girdled around the base, it will die.

If you have any concerns or questions about your plant material, please contact us.

Hope everyone has a great spring!