Boulder city officials are reminding people that winter watering is essential to keep trees healthy as winter conditions remain dry and warm.

Trees that don’t get watered in the winter can cause issues that might not show up until the following spring, a city of Boulder news release said. This can include branch dieback, reduced leaf size, chlorosis and dying trees.

Winter drought conditions can also stress trees and make them more susceptible to insect attacks, the release said.

The region is naturally a semi-arid, shortgrass prairie that would have few trees without irrigation, according to Boulder officials. Urban trees that are properly placed and well-maintained are an asset to the environment and communities, drawing down carbon, creating shade, intercepting stormwater to reduce flooding, and improving air quality and public health, according to the release.

Trees that are the most at-risk from dry winter conditions include those that have been recently planted, evergreens and shallow-rooted deciduous trees like maples, poplars and lindens.

To help people maintain the health of their trees, Boulder officials listed winter watering tips, which are as follows.

• Water when the air and soil temperatures are above 40 degrees Fahrenheit and there is no snow on the ground.

• Water early in the day so water can soak in before freezing night temperatures.

• Do not water frozen soil.

• Water once or twice a month with 15 gallons per inch of tree trunk diameter. Newly planted trees need 15 to 20 gallons.

• Water at the tree’s dripline, which is the outermost circumference of the tree branches. A slow, deep soak reaches the fine feeder roots that are up to 8 inches below the soil surface.

• Hand watering, a soaker hose or a drip application is best.

• Leave irrigation systems off in the winter to prevent frozen and broken equipment.

• Minimize the use of deicers and other pollutants, since melting snow can carry them into storm drains.

• Shovel clean snow from sidewalks and driveways around the dripline of the trees to help insulate roots and water the tree as the snow melts.

• Put two-to-four inches of wood chip mulch from one inch away from the base of the tree out to the dripline to retain soil moisture.

• During dry, warm periods, water trees every few weeks.

More tree care information is available on the city of Boulder’s website.