Flaming can be an effective nonselective, nonchemical method of weed control. It has been more effective against broadleaf weeds than grasses. Experiments were conducted with a conveyor bench burner apparatus to evaluate flaming to kill broadleaf and grass seedlings at the 0- to 2- and 2- to 4-leaf stages. Most 0- to 2-leaf green foxtail seedlings were killed when flamed at 2, 4, and 6 km/h conveyor speed. A few plants survived when flamed at 8 km/h. Green foxtail seedlings at the 2- to 4-leaf stage were more tolerant to flaming than 0- to 2-leaf green foxtail, and substantial numbers of plants survived at all flaming speeds except 2 km/h. Barnyardgrass was more tolerant to flaming than green foxtail, and many 0- to 2- and 2- to 4-leaf seedlings survived after flaming. However, fresh weight of the live plants at 14 d after treatment was reduced. Some large crabgrass plants survived flaming at both growth stages. Flaming at 2 km/h reduced seedling number and fresh weight, but there was significant regrowth. Common ragweed was more susceptible to flaming at the 2- to 4-leaf stage than at the 0- to 2-leaf stage. Redroot pigweed and common lambsquarters were susceptible to flaming at both 0- to 2- and 2- to 4-leaf stages.
Nomenclature: Redroot pigweed, Amaranthus retroflexus L. AMARE, Common ragweed, Ambrosia artemisiifolia L. AMBEL, Common lambsquarters, Chenopodium album L. CHEAL, Large crabgrass, Digitaria sanguinalis L. DIGSA, Barnyardgrass, Echinochloa crus-galli L. ECHCG, Green foxtail, Setaria viridis L. SETVI