Browse on keywords: water quality herbicide
Search results on 05/22/13
356. Anon.. 1989. Fine-tuning mix water.. Agrichemical Age, October 1989.
Herbicide performance can be greatly affected by the quality of the tank mix water. Water-soluble post emergent herbicides, such as glyphosate and phenoxys, seem to be most sensitive. Three factors are important: water pH; cation concentration; and suspended solids. Post-emergent herbicides perform best when the tank mix is acidic. Optimum for phenoxys and glyphosate is pH 3-4. Hard water will reduce activity when herbicides are mixed and stored for many hours. Cation effects on deactivation are as follows: most severe - Fe++, Fe+++, Al+++; severe - Ca++, Zn++; moderate - Mg++; minimal - K+, Na+. Water with suspended dirt or organic matter will bind with many herbicides.
1095. Brown, D.B., D. McCool, R. Papendick, and L. McDonough. 1985. Herbicide residues from winter wheat plots: effect of tillage and crop management.. J. Environ. Science 14:521-532.
Studied the magnitude and persistence of residues of metribuzin and bromoxynil octanoate in winter wheat plots under various tillage management. Herbicide loss was greatest where erosion was high. Herbicide runoff was extended under winter conditions in eastern WA, and there was little movement or degradation of herbicides when the ground was frozen. The half life of metribuzin was 102-112 days.
1308. Choi, K.L., S.S. Que Hee and R.G. Sutherland. 1976. 2,4-D levels in the south Saskatchewan river in 1973 as determined by a GLC method.. J. Environ. Sci. Health, Bll(2), 175-183.
2,4-D levels in the South Saskatchewan River near Saskatoon in 1973 at the height of the spraying season, and at harvest time were determined by a method involving direct GLC analysis, alkaline hydrolysis, followed by n-butylation of the liberated free acid after acidification of the alkaline solution, and confirmed by subsequent n-octylation. GC/MS also confirmed the presence of 2,4-D. 2,4-D was detected during the spraying season but not at harvest time or in river mud samples. The average level was ca. 2ug of acid equivalent to 2,4-D per liter of river water at the height of the spraying season.