Lack of snow in the winter doesn’t just affect Colorado ski areas, it also impacts valued landscape plants. Colorado’s dry winters are the number one killer of trees, shrubs, and other plants. However, when it comes to drought, knowing the causes, implications, and what you can do about it will ensure your landscape survives the winter and thrives in the spring.
A drought is a prolonged period with less-than-average amounts of rain or snow in a particular region. According to the AMS Glossary pf Meteorology, snow drought occurs when there is a period of abnormally low snowpack for the time of year in question. The impacts are widespread, affecting ecosystems, reservoir levels and operations, water resource management, tourism, and water recreation.
What Causes A Drought?
A drought is caused by drier than normal conditions that can eventually lead to water supply problems. Really hot temperatures can make a drought worse by causing moisture to evaporate from the soil. Just because a region is hot and dry doesn’t necessarily mean it is going through a drought. Droughts only occur when an area is abnormally dry. Here’s why:
Rain and snow don’t fall evenly across Earth. Some regions are routinely wet, and others are routinely dry. From season to season — and from year to year — the amount of rain or snow in a location can vary.
However, over a period of many years, the average amount of precipitation in a region is consistent. For example, in the deserts of the American Southwest, the average precipitation is less than 3 inches per year. But the average yearly precipitation in Atlanta is about 50 inches.
When a particular area gets less rain than usual, the soil gets much less moisture, too. The soil starts drying out and plants die. When this pattern continues for several weeks, months or years, the flow of streams and rivers decreases and water levels in lakes, reservoirs and wells fall. Eventually, the unusual dry weather causes water supply issues, and the dry period becomes a drought.
Implications Of Drought On Landscape Survival
Drought, or periods of water shortage, impact plants in a variety of ways by affecting how much water is available for plant use. If plants cannot tolerate lack of water various symptoms will appear, including:
- Stunted growth
- Increased disease susceptibility
- Increased susceptibility to water injury
- Death or injury when a warm period is followed by a very cold period in winter
Initially, growth stops and foliage wilts as plants become stressed. Unless supplemental irrigation is provided, plants may eventually die. When this happens will differ based on the plant’s ability to withstand drought.
What You Can Do About Drought
During a drought period, plants become dehydrated. Therefore, watering plants in the winter is the best way to mitigate the challenges of drought.
Water only when air temperatures are above 40 degrees F. Apply water at mid-day so it will have time to soak in before possible freezing at night. A solid layer (persisting for more than a month) of ice on lawns can cause suffocation or result in matting of the grass.
Plants receiving reflected heat from buildings, walls and fences are more subject to damage. The low angle of winter sun makes this more likely on south or west exposures. Windy sites result in faster drying of sod and plants and require additional water. Lawns in warm exposures are prone to late winter mite damage. Water is the best treatment to prevent turf injury.
Monitor weather conditions and water during extended dry periods without snow cover – one to two times per month.
When the leaves fall and the winter turns cold, it can be hard to think about pulling out the water hose. That is why our team at Front Range Arborists is equipped with the tools and professional experience to get the job done for you!
Take advantage of our Winter Water program to help valuable trees and shrubs survive the winter and thrive in the spring. Fill out our online form to request your free estimate today!
