LOVELOCK - Fall is an excellent time to manage weeds, especially biennial and perennial weeds. In particular, Dandelions, Russian knapweed, Hoary cress (white top) and most thistles are much easier to kill while they are in the rosette stage of growth and prior to surviving a winter.
In the autumn, the sap flow of perennial weeds is downward to the canes and roots. This downward flow carries the non-selective herbicides into the root system and kills the entire plant.
In the spring, sap flow is primarily upward toward developing leaves and flowers. Because of this, herbicides applied to perennial weeds before they flower will tend to remain in the leaves and only kill the top part of the plant, leaving the root system intact and capable of re-sprouting.
In general, the application window runs from early September through October depending on where you are in the state and what weeds you are targeting. Some weeds, such as Russian knapweed, are best controlled with a herbicide application after the first frost.
The most common herbicides used for broad-spectrum control of many weeds in the fall is glyphosate (Roundup) for grasses and broadleaves and 2,4-D or dicamba (Banvel, Clarity, etc.) for broadleaves. A combination of these products may be the best solution for a mixture of different perennial weeds.
Important considerations:
Make sure that the foliage on the weeds appears relatively healthy and capable of absorbing the herbicide spray. Plants that have been damaged by insect feeding, drought, harvest equipment, frost, or autumn leaf senescence are not good candidates for fall applications.
Make sure to use adequate herbicide rates, high spray volumes, and get good spray coverage over the plant for effective kill.
The use of a surfactant (an additive that improves the effectiveness/performance of herbicides) will also improve the efficacy of the weed control chemicals. Also, you should check the pH and hardness of the water being used to mix the chemicals, as these will affect how well they control the targeted weeds.
Favorable air temperatures should be a consideration immediately before, during, and after application. In general, the warmer the better, with daytime high temperatures in the mid 50s at a minimum. Cold nights and cool, cloudy days will reduce and slow the effectiveness of the applications. The more active the weeds are growing, the better the herbicide performance.
If you would prefer not to use chemicals to control weeds in your yard, any time of year is appropriate to hand-remove weeds. For common lawn weeds such as dandelion and plantains, there are a host of tools available (commonly called "weed poppers") that are extremely effective in the complete removal of "tap-rooted" weeds. A shovel or spade can also be used but may disturb excessive turf removing the weeds.
If you don't mind bending over or getting on your hands and knees, you can achieve the same result with a sturdy pocket knife. If you commit a few minutes a day to hand-removal, you will be surprised what an impact you can have over several days of effort.
However, hand-removal of creeping weeds with fibrous root systems is often very limited in success and can be quite frustrating in terms of the effort expended and the limited level of control.[[In-content Ad]]
