Browse on keywords: weed weed control
Search results on 12/12/13
1387. Cony, Ann. unknown. First of kind natural herbicide reported.. Sacramento Bee (newspaper).
Richard W. Jones, of UC-Berkeley, reported the use of a natural, self-destructing herbicide capable of killing a wide variety of weeds. It is made from a common soil fungus Gliocladium virens which is artificially charged with nitrogen, thus causing it to produce a compound that is toxic to plant roots for about 2 weeks. The herbicide can kill plant roots as well, but it doesn't hurt plant stems. Thus timing and placement are crucial. The herbicide prevents germination and emergence of weed seedlings, and also produces an antibiotic that protects crop seedlings from rotting.
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.
2221. Goldstein, Walter A.. 1986. Alternative crops, rotations, and management systems for dryland farming.. Ph.D. dissertation, Agronomy and Soils, WSU.
This work covers a number of research areas, including the use of edible white lupine as an alternative crop, the use of black medic in rotation with spring peas and winter wheat (the PALS concept), performance of winter wheat as influenced by rotations, fertilization, and fumigation; rotational effects of medics; wheat interference with weeds; costs and returns of alternative systems; comparison of agronomic effects of conventional, organic, and biodynamic management. The PALS (perpetuating alternative legume system) concept was field-tested using a pea + medic - medic GM - winter wheat rotation with limited inputs of agrichemicals and tillage. This system was more economic using market prices of commodities at both a low and high yield level. With government support prices, the PALS system was competitive in the low yield situation, but not the high. Rotational effects appeared to suppress weeds in wheat with the medic compared to a continuous cereal system.
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.
3278. Parish, S.. 1990. A review of non-chemical weed control techniques.. Bio. Agric. and Hort. 7:117-137..
This paper discusses non-chemical weed control techniques for cereal and row crop production. Recommendations include a good rotation scheme, delayed sowing of winter wheat to avoid autumn weeds, and a cereal variety with long straw and an initially prostrate growth habit to smother weeds. Other techniques to smother weeds include increasing the seeding rate by up to 20%, sowing cereal in bands, and undersowing with mustard in areas where winter is severe enough to kill the mustard. A thin-tined implement can be used for pre- and post emergence operations and blind harrowing, just before crop emerges. Combine modifications were recommended in order to separate the weed seeds from the grain, straw and chaff to avoid returning weed seeds to the soil. Biological control in the form of natural enemies of weeds is currently being researched and appears very successful.
10118. Washington Assoc. of Wheat Growers. 1991. Glean withdrawal.. Growers Guide, Apr. 1991, p. C10.
Cereal growers in seven Great Plains states will no longer be able to use Glean herbicide from DuPont because of the spread of weed biotypes resistant to the herbicide. When Glean is used repeatedly, especially in monoculture cereal production, the selection pressure on resistant biotypes can increase. The product will still be available in the Pacific Northwest where the environmental conditions are favorable for faster product breakdown so the selection pressure for herbicide resistant biotypes is decreased. Recommended resistance management guidelines are rotating crops, changing herbicide programs, using shorter-residual herbicides and not letting weed escapes go to seed.