Browse on keywords: weed herbicides
Search results on 06/19/13
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.
1891. Erickson, L.C., C.I. Seely, and E.W. Whitman. 1948. Using 2,4-D for selective and non-selective weed control.. ID Extension Bull. 172.
Early discussion of the use of 2,4-D. Various formulations, application rates, methods. Grain yields reduced 5-15% when treated with enough herbicide to kill 90% of common annual weeds.
2424. Hannesson, H.A., R.N. Raynor, and A.S. Crafts. 1945. Herbicidal use of carbon disulfide.. Univ. California Agr. Expt. Sta. Bull. 693.
Temporary soil sterilant (6-8 wk). Studied diffusion and action of carbon disulfide in soils. Particularly effective on deep-rooted perennials. Requires hundreds of pounds per acre for effective treatment. Often a growth response to a following crop, due to S additions.
3045. Swanson, C.L., and H.G. Jacobson. 1950. Influence of cultivation and weed killers on soil structure and crop yield.. Soil Sci. 69:443-457.
Studied corn and carrots in CT. Some benefits from cultivation, particularly with soil crusting. Measured macropores and micropores.
8439. Morrow, L.. 1990 June. Producers or killers?. Growers Guide, p. A5, Colfax, WA 99111.
A healthy organism will withstand external stress better than an unhealthy one. Proper fertility will help plants compete better and need less pesticides to protect them. Cheap herbicides such as 2,4-D injure the wheat and reduce yields, and thus have a cost to their use. Research has shown the chloride ion to suppress some disease, but all the emphasis is on fungicide use.
8608. Young, F.L.. 1990. IPM systems research.. unpublished handout from USDA-ARS Weed Research Unit, Pullman, WA 99164.
The IPM Weeds study near Pullman, WA uses two 3-yr crop rotations, two tillage systems, and three weed management (herbicide) levels. Spring pea average yields after 3 yr were higher with chisel plow than with moldboard plow, slightly responsive to increased weed management level, and highest with maximum weed management/chisel plow combination.