Question: I have grassy weeds in my lawn. How can I control their spread?

Answer: Because it is late spring, pre-emergent herbicides cannot be applied. Grass weeds begin growth from mid-April to mid-May in the Front Range, and pre-emergent herbicides should be applied two to four weeks before these dates. One option to eradicate grassy weeds is by using post-emergent herbicides. These herbicides are usually applied sprays. After the initial application, a re-application may be done 4-7 days later, if necessary. To minimize chemical damage to the lawn, irrigate with one inch of water two days after the last treatment. Ideal air temperature should be between 70 - 85 degrees. To prevent weed seeds from germinating, keep lawn height at 2.5-3". Proper irrigation is also necessary in preventing weed germination. For more information read Fact Sheet #3.101 - “Grassy Weed Control in Lawns” and #7.202 - “Lawn Care.”

Question: I just moved to Colorado and want to plant an Aspen tree. Is this a good choice for the Front Range?

Answer: If you live at an altitude lower than 6500 feet, it is suggested that you do not plant aspens. At lower altitudes, aspen are prone to many cultural and health problems. Marssonina, a fungus, injures mature leaves with brown flecks surrounded by a yellow halo; immature leaves exhibit spots with white centers. When severely infested, the leaves, petioles and shoots turn black.
Septoria leaf spot is another fungus found on aspen planted in urban areas. Symptoms of Septoria are distinct tan circular spots with black margins. Small “pimples” may occur in the center of the spot. The spots become black or brown and may eventually cover the entire leaf. Leaf Rust is caused by Melampsora fungi. Leaf rust does not kill the tree, but causes unsightly small yellow-orange abscesses on lower leaf surfaces. Leaf rust is most visible in late summer and early fall.
Most of these fungi can be controlled my cleaning up all fallen leaves, doing correct watering practices, and using fungicides when necessary. Fungi are airborne and can appear on aspen despite your careful practices. Buying resistant aspen hybrids may help, but are not a guarantee to prevent against all disease. For more information refer to Fact Sheet #2.920 - “Aspen and Poplar Leaf Spots.”

Question: My gooseberry did not produce much fruit last year. What’s wrong?

Answer: Gooseberries, currants and jostaberries should be pruned for good yield. Gooseberries produce more fruit on younger wood, therefore remove wood older than three years. Pruning should be done before the buds swell. Controlling weeds near the berry plants may also increase yield. Gooseberries respond well to heavy mulching and sufficient irrigation. Recommended varieties for Colorado are ‘Pixwell’ and ‘Welcome’. For more information read Fact Sheet #7.005 - “Currants, Gooseberries and Jostaberries.”

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This page updated:  June 23, 2006