Question: Several of my shrubs have broken branches from this winter's heavy snows. Can I cut these out now?

Answer: Broken branches can be removed from trees or shrubs at any time of year. Early spring is a great time for pruning; the structure of the shrub is easily visible when the branches are bare. However, spring-flowering shrubs bloom on wood produced last fall, and pruning before bloom reduces the number of blossoms. To maximize the spring show, it's suggested that spring-flowering shrubs be pruned after they bloom.

Q: Last year my lawn had crabgrass. How can I avoid that problem this year?

A: Crabgrass is one of several summer annual grasses that invade our lawns. Last summer's crabgrass, foxtail and goosegrass plants produced thousands of seeds before they were killed by frost. These seeds will begin to germinate when soil temperatures reach 55 to 60 degrees, usually around mid-April. Both cultural and chemical techniques can be used to manage these invaders.

A healthy lawn will usually provide enough competition to keep weeds at bay. Healthy growth can be encouraged through such cultural practices as mowing at appropriate height, proper watering and fertilizing, and annual core aeration. Pre-emergent herbicides can also be used to help control grassy weeds in established lawns, but it must be applied prior to the germination of the weed seeds. It's usually recommended that pre-emergent herbicides be applied during the last half of March. If you opt to use an herbicide, be sure to follow all label directions.

Q: Any landscaping suggestions for a newcomer to Denver?

A: Have a sample of your soil tested. Test results will tell you about the pH and nutrient levels in your soil. They will also provide information on the texture and level of organic matter. These tests are available through the Colorado State University soil-testing lab and through independent labs.

For more information, call the Colorado State University Cooperative Extension office in your county or visit www.ext.colostate.edu.

Ann Montague, Colorado State University Cooperative Extension master gardener, Broomfield County