Source:
Weed 'Em and Reap Part 1: Tools for Non-Chemical Weed Management in Vegetable Cropping Systems [DVD]. A. Stone. 2006. Oregon State University Dept. of Horticulture. Corvallis, Oregon. Available at: http://www.weedemandreap.org (verified 17 Dec 2008).
Featuring
Louie Murgg, Forevergreen. Langley, BC, Canada.
Brian Maupin, Washington State University. Mt. Vernon, WA.
Audio Text
Louie Murgg: The infrared machines are designed to work with a very low amount of propane fuel which usually goes through a tank like in here, through the regulator, through the holes and through a ceramic plate where it's being ignited. The ceramic plate is very thin and fragile and that’s where the mixture of air and fuel goes together, being ignited and creates the heat down here.
The application is also a surface application. The heat penetrates approximately 1/8”. It does not disturb the soil in any kind of way. The consumption of the fuel is approximately 1 pound an hour. A tank will last for approximately 7.5-8 hours of continuous work. The commercial machines which are going to be developed for agricultural use are designed to make really precise row applications and very easily adjusted without tools anywhere from 6 inches to 16 feet in width. Also a protection shield can be mounted on the side so you do have the ability to touch the crop on this side without doing any damage to them.
Brian Maupin: The biggest advantage of using an infrared versus an open flame is the consumption of the fuel, the precise operation and also the low noise. By using an infrared in a method like this, it will reduce the use of fuel by approximately 80%.
This was burned about 18 hours ago in very warm, sunny conditions, very optimal. If it was wetter, more rainy, it would take a bit longer. This is what we find is really good results. All the above ground matter is dead. These plants are a bit large, so there might be some re-growth. It certainly has knocked them back a bit. Coming in 10 days to 14 days, if we do get re-growth, we will be able to flame that again and really knock it down.
These weeds were a bit large, for this sort of technology, but it definitely has stunted them a bit, another treatment or two would probably remove them completely. This is where the unit did not get through, along where the plant row is, and you can still see a few plants that are alive.
When using this unit, I was very careful to not rub the side of the unit up against the stalks of the broccoli. Although, the top of the unit did move the leaves across and as you can see, there is no damage. All of the heat is focused at the ground, so it doesn’t really affect the leaves as you push across.
Ten Days After Treatment
This plot was treated with the burner about 10 days ago. As you can see, we have real nice control of the young weeds. Here’s a plant that was a bit larger when it was treated, so there is some re-growth, but the broccolis are doing just fine and we actually have fairly decent coverage right up close to the plants.