By Kathleen Cue, Nebraska Extension Horticulture Educator
In the midst of September, if weed management isn’t on your autumn to-do list, it definitely should be. Fall is the best time to be applying herbicides to perennial weeds. Why is this so? As plants ready for winter, sugars produced in leaves are transported to the roots for storage. With herbicide applications, the plant’s internal transport allows herbicides to move readily from leaves to roots, providing for excellent distribution and better control.
Recognizing something as a weed is not enough. Identification is critical to making sure your time, labor and resources are used to good effect. Crabgrass and foxtail, the bane of many lawns and gardens, are annual plants and will die with the first hard freeze. So using herbicides on annual plants in the fall doesn’t make a lot of sense. Dandelion, ground ivy, brome grass, and poison ivy, however, are perennial plants and management efforts will be more effective now. Plan to get at least two applications of the herbicide down before the first hard freeze, spacing the timing of the applications according to the label directions. If you need help with identifying the weeds in your garden and landscape, the Nebraska Department of Agriculture has an excellent reference, Weeds of the Great Plains. Information for purchase of this book may be found here: https://nda.nebraska.gov/forms/nw11.pdf .
It’s surprising how the presence of the word “weed” in a plant name brings others to the conclusion that the plant should be removed... immediately. So if you have Joe Pye weed, butterfly milkweed, or ironweed, this doesn’t mean you should reach for the herbicide. These are beautiful plants in their own right and benefit pollinators to boot. While a pristine lawn may be considered the ideal, gardeners can choose to leave some weeds in out-of-the-way places to provide food for pollinators.
Sometimes the word “weed” in a plant name is justifiable, like ragweed, which causes a lot of problems for allergy sufferers. Clients once inquired about the “interesting” plant that appeared on their property. The plant was none other than giant ragweed and the clients thought the ragweed’s growth rate was so amazing they decided to keep it! This proves once again that beauty is ultimately in the eye of the beholder.
Photo Below: Giant Ragweed
Go to Dodge County Horticulture Web Page for more gardening information.