This article is provided by Chris Galbraith, MSU/OSU Extension & Jenna Falor, MSU Extension.
Late-season weed management is essential to consider when developing a weed control plan for your operation. Despite one’s best efforts, weeds can often escape early-season control. This can be a result of poor timing, missing the plants with cultivation, spray applications or flaming, or due to herbicide resistance. If allowed to reach reproductive maturity, escaped weeds can cause management problems in future years due to replenishment of the weed seedbank. These larger weeds can also harbor crop pests and diseases, interfere with harvest by obstructing equipment, or degrade final crop quality through contamination from weed residues.
Management practices for escaped weeds are notoriously limited due to the difficulty of controlling weeds when they have reached a significant size. Weed wipers use an applicator made of an absorbent material, such as sponge or a rope wick, that is saturated with herbicide and used to contact weeds growing above the crop canopy, killing the weeds but leaving the crop unaffected. The downsides of this method include a lack of herbicide options effective on larger weeds, limited efficacy on herbicide-resistant populations (depending on what product is being applied), and its unsuitability for use in organic systems. Another option is sending in hand weeding crews to manually weed the fields, which is particularly common for managing escaped weeds in vegetable production. While this method does tend to be effective, the labor is expensive, time-consuming, and hard monotonous work for employees.
The major manufacturer and supplier of electrical weeding equipment in the United States is The Weed Zapper, a Missouri-based company that began production in 2017. Electrical weed control technology has also been developed by the Brazilian company Zasso and the European companies AgXtend, Rootwave, and Crop.Zone. While electrical weeders from foreign companies are as of yet rare in the U.S., familiarizing oneself with the technology that has been developed overseas shows the versatility of this technology in different cropping systems and gives a clue as to the future of the equipment in modern agriculture.
Pro-environmental attributes of the equipment are that it does not disturb the soil and does not require the use of any chemical herbicides. Electrical weeding provides systemic control of even larger plants, making it an effective option for controlling weed seed bank inputs by terminating weeds at or prior to reproductive maturity. Similar to mechanical weeding and certain herbicides, it is non-selective and therefore caution must be taken to prevent crop injury. This typically restricts in-season use to crops with low-canopy growth habits that don’t come into the path of the electrode. While this limits the application of electrical weeding, there still remains many crops where growers might benefit from integrating this equipment into their weed control plan.
Read the full article “Electrical Weed Control in Vegetables and Field Crops”.
View the factsheet “Basics of Electrical Weed Control”.