Electricity as an effective weed control tool in non‐crop areas

Abstract

While weed management is often thought of as an agricultural issue, weeds are also problematic for homeowners, public space managers and utilities. In these situations, weeds are typically hand‐pulled, mechanically treated or managed via herbicides. Hand pulling and mechanical treatments are labour‐intensive, and all control methods may have unintended off‐target impacts, necessitating new alternatives for weed control. We have developed a method of using electricity to effectively manage unwanted plants. A series of experiments was conducted with the aim of developing operating protocols with consideration to specific scenarios: we tested a system on Morus alba (mulberry) and Ulmus pumila saplings, determined the response of Tamarix spp. (tamarisk) to different electricity doses, evaluated electricity as pre‐emergent weed control in xeriscaping, and tested the ability of electricity to prevent climbing growth by the vine Convolvulus arvensis (field bindweed). Tests on M. alba and U. pumila demonstrated that low doses of electricity applied over several days are effective in killing trees up to 20 cm in diameter. The Tamarix experiment showed that the plants displayed typical dose–response characteristics with higher doses leading to less plant growth. Results of the pre‐emergent weed control experiment demonstrated the excellent ability of electricity to prevent weed growth, with treated plots having a mean weed cover of 4% compared to 94% in control plots after 4 months. Finally, electricity was shown to be 100% effective in preventing C. arvensis from climbing poles. Our results indicate that electricity is a viable alternative to manual, mechanical or chemical methods for small tree control, pre‐emergent weed control in xeriscaping, and prevention of climbing weeds.

Exploring the potential of electric weed control: a review

“…When the application was increased to 200 V, mortality was 79% at 300 s and 90% at both 420 and 540 s (Sahin and Yalınkılıç 2017). Similarly, Lehnhoff et al (2022) found that when treating tamarisk ( Tamarix spp. L.) with experimental continuous plant–electrode contact technology at 2 mA for 0, 12 or 24 h, a reduction of 0%, 37%, and 75% in plant biomass can be seen.…”

“…However, the development of applicable electric weed control technology must prioritize the user's safety and those nearby during operation. Lehnhoff et al (2022) recently analyzed the suitability of such applications to xeriscaping using an experimental mesh screen over urban groundcover that was consistently exposed to a safe, low-level current of 6 mA for 4 mo (continuous plant–electrode contact). Compared with the untreated control at 64%, this resulted in only 11% coverage of carelessweed ( Amaranthus palmeri S. Watson), silverleaf nightshade ( Solanum elaeagnifolium Cav.…”

“…However, Lehnhoff et al (2022) determined that prolonged exposure of up to 30 h to low-voltage electrical applications (10 to 250 mA) with experimental continuous plant–electrode contact technology was able to effectively kill white mulberry ( Morus alba L.) and Siberian elm ( Ulmus pumila L.) trees up to 20 cm in diameter. Further, C. arvensis was controlled from climbing up metal screen–wrapped wooden poles with the constant application of 300 V for approximately 6 wk (Lehnhoff et al 2022). Such applications may be beneficial to remove undesirable vegetation in urban and industrial settings without chemical use (Lehnhoff et al 2022).…”

“…Further, C. arvensis was controlled from climbing up metal screen-wrapped wooden poles with the constant application of 300 V for approximately 6 wk (Lehnhoff et al 2022). Such applications may be beneficial to remove undesirable vegetation in urban and industrial settings without chemical use (Lehnhoff et al 2022). However, there is no indication that they will be effective for transient interrow electric weed control applications on mature crops as in Bongard et al (2022).…”

High seeding rates, interrow mowing, and electrocution for weed management in organic no-till planted soybean

“…Another physical weed management tactic is weed electrocution, a method patented in the late 1800s (Opp and Opp 1952). The technology was investigated in sugar beets ( Beta vulgaris L.) in the 1970s (Diprose et al 1985; Rasmusson et al 1980; Vingneault and Benoît 2001), and there has recently been renewed interest, likely due to the increase in herbicide-resistant weeds (Heap 2023) and the development of new electrical weeding machines (Bloomer et al 2022; Lati et al 2021; Lehnhoff et al 2022). The flow of electricity through a plant generates heat, which causes water molecules inside the plant vasculature to vibrate at a high intensity, resulting in damage to cell walls and destruction of tissues, ultimately leading to plant death (Lati et al 2021; Vingneault and Benoît 2001).…”