The Bureau of Land Management is testing a new way of killing noxious weeds: zapping them with hot foam as an alternative to herbicides.
The BLM’s Eugene district is in the second year of a three-year lease of the weed-killing system, called Waipuna. Developed in New Zealand in 1993, it’s used worldwide to kill unwanted vegetation as well as remove chewing gum and graffiti and clean monuments.
The treatment kills about 90 percent of the targeted weed, in this case false-brome, a foreign grass invading Western Oregon with alarming speed.
“The plants are shocked instantly and die within four hours,” BLM worker Eric Norstog told The Register-Guard.
Waipuna, from the Maori words for “water” and “clear spring,” uses a nontoxic, biodegradable foam created by infusing hot water with a sugar extract from corn and coconut.
The hot-foam method is slower than spraying weeds with a herbicide, but it’s touted as an environmentally friendly solution for about the same cost. It’s also more versatile; it can be used in windy conditions and light rain, unlike most pesticides.
Source: The Seattle Times Oct 17, 2004.