Evaluation of the herbicides Crosser and Vaquero for weed control in tropical grasslands.
During the 2001
rainy season, two experiments were conducted in La Mancha,
Veracruz, Mexico, in order to evaluate the effect of the
herbicides Crosser (15 g of picloram + 150 g of 2,4-D/L) and
Vaquero (30 g of triclopyr + 120 g of 2,4-D/L) for controlling
Lagascea mollis Cav. and Baltimora recta L. in a grassland of
Cynodon plectostachyus Vanderyst. In 2002, the experiments
were repeated in La Colonia Independencia, Ver., in a
grassland of Digitaria decumbens Stent., infested with Senna
obtusifolia (L.) Irwin & Barneby. Both herbicides, Crosser
and Vaquero were applied at 0.75, 1, 1.25, 1.5 and 2 l/100 l of
water; Full-Mina 4 (480 g of 2,4-D/L) at 1 and 2 l/100 l of
water, and Esteron 47-M (400 g of 2,4-D/L) at 2 l/100 l of
water, were also evaluated and a weeded control was
included. A Completely Randomized Block Design with four
replications was used for all the experiments. Weed control
and grass toxicity were evaluated at 15, 30 and 60 days after
treatment application. Crosser controlled B. recta and S.
obtusifolia at 0.75 l/100 l of water, whereas to control L.
mollis, it was necessary to apply it at 1.5 l/100 l of water.
Vaquero also controlled B. recta and S. obtusifolia at 0.75
l/100 l of water, but it had no good control of L. mollis. None
of the herbicide treatments caused any toxicity to the grasses.