Lack of available subsoil moisture has been taking its toll on trees throughout the Rocky Mountain and High Plains region. September is an important month to prepare trees for winter survival. However, there are many misconceptions on how to effectively water trees in your landscape.

John Cretti, Horticulturist and Colorado's Master Gardener has some important tips on how to properly water trees throughout the late summer and early fall.

Deeply saturate the soil around the dripline of trees and shrubs. The dripline is the area on the ground beneath a tree's outermost branches. For larger, maturing trees, the area beyond the dripline needs to be watered, too.

Use a frog-eye sprinkler to water slowly and apply water at a low arc. This allows the water to soak down deeply to a depth of 12 inches or more. Soaker hoses or a garden hose set a low pressure can be used, also.

Set the frog-eye sprinkler at the outer edge of the dripline. Move around the drip zone (approximately every 10 to 15 minutes) to allow for overlap and complete watering of the root zone.

How much water does a tree need? Use this green thumb tip to determine how much water a tree needs: Measure the tree trunk's diameter at knee height, then multiply by 10. For example: a tree with a 7-inch tree trunk needs 70 gallons of water.

How long should you water? When using the frog-eye sprinkler set a medium pressure, multiply trunk diameter by 5 to calculate total watering time. For example: A 7-inch tree should be watered for 35 minutes; slow watering allows water to percolate deeply where the roots can absorb water.

During extended dry periods without snow or rainfall, water trees every five to six weeks when the soil is unfrozen. Water early in the day to allow the water to soak down deeply.

For more details on how to care for your trees, consult John's book "COLORADO GARDENER'S GUIDE -- The What , Where, When, How and Why of Gardening in Colorado."

Tune in to the JOHN and JERI SHOW on 630 KHOW Saturday morning from 7 to 9 for more Gardening in the Rockies Tips and listen for "Ask the Gardener" questions featured on 7NEWS.