Approximately three weeks ago we began receiving calls from clients reporting symptoms their trees were exhibiting in their new leaves and branch growth. We had suspicions we were starting to see the beginning developments of fire blight in some of our ornamental trees. We started setting up visits with our clients reporting these symptoms. Once we started completing the visits we quickly were able to diagnose the symptoms as being associated with fire blight.
Fire blight infects only certain species of the Rose family in our area. It is most prevalent in crabapples, apples, mountain ash, pear (including ornamental pears), and hawthorns. Sometimes on rare occasions it can infect serviceberries, cotoneasters, flowering quince, and pyracanthas. We typically do not see it infect the shrub species as often as it does the trees previously mentioned in our region.
The symptoms are relatively easy to diagnose including: leaves with a wilting appearance, sometime with brown to orange-ish coloring, the bark is discolored (compared to healthy twig/branch bark) with the tips of the branches having a crooked appearance-as if in a “shepard’s crook”.
Fire blight is a bacterial infection often spread by a contaminated pruning tool, insects, wind or splashing rain in the early spring when our temperatures reach roughly 65 degrees. Some years the infections are worse than others. This year we have diagnosed trees with this disease that in previous years had not been infected. Warm and humid springs are very conducive to the development of the bacteria. The bacteria over-winters on branches and twigs.
Our best recommendation if your tree has been diagnosed with fire blight, is to schedule a winter pruning service with your Denver Tree Specialists, as well as set up an early spring preventive application on the infected trees. While the spray is by no means a cure-all, it is a tool we have to aid in the reduction of the symptoms. One of our arborists can visit your property and evaluate the care and treatment of your trees, for a best management plan may be developed.
For further information regarding Fire Blight please click the link below:
Irrigation Schedules for Mid-Summer
With the change of the season to summer, the heat is on! It is important to adjust and modify sprinkler control clock settings as our temperatures change during the growing season. Often times when a sprinkler system is activated in early spring, with our cooler nighttime temperatures and the sun positioned lower in the sky, we are able to use much less water. When the summer solstice arrives our daytime temperatures are often well above 85 degrees. This is a good time to adjust the sprinkler control clock settings to increase the watering times as needed for each zone at your property, as well as adjust the time of day the watering is scheduled for.
This is also a great time to re-examine the nozzles on each sprinkler head to ensure they are working properly and adjusted accordingly. And don’t forget to check any micro-spray nozzles and to check drip emitters. And remember, as trees and shrubs grow they need to have more drip emitters added, as the plant will need more water.
As always please be conscious of water conservation efforts and be sure to contact your local water district to ensure you are following their guidelines and/or restrictions for seasonal water use.
For more information regarding sprinkler systems maintenance please click on the link below: