Record Details
Factors influencing the effectiveness of activated carbon used to protect newly-seeded grasses from herbicides
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Factors influencing the effectiveness of activated carbon used to protect newly-seeded grasses from herbicides |
| Names |
Burr, Ronald J.
(creator) Appleby, Arnold P. (advisor) |
| Date Issued | 1969-07-22 (iso8601) |
| Note | Graduation date: 1970 |
| Abstract | Previous research has shown that activated carbon is effective in inactivating certain herbicides applied as a preemergence treatment. Studies were conducted in the greenhouse to determine the influence of various factors on the ability of activated carbon to inactivate herbicides applied after carbon application. Field studies were conducted to determine the effect of rate of activated carbon on its ability to inactivate herbicides applied after a band of carbon, 1.0-inch wide, had been applied. In the greenhouse studies, annual ryegrass (Lolium multiflorum Lam.) was used as the test species, Aqua Nuchar-A was the activated carbon used, and 3-(3, 4-dichlorophenyl)-1, 1-dimethylurea (diuron) was the herbicide used. The influence of planting depth on the protection obtained was determined by planting seeds 0.25, 0.50, 0.5, and 1.0-inch deep. Plants growing from seeds planted 0.50 inch deep received less protection than plants growing from seeds planted at the other three depths. Sandy loam and clay loam soils were used to determine the influence of soil type. At least three times more activated carbon was required with a sandy loam to obtain the same protection as was obtained on a clay loam soil. The influence of the rate and band width of activated carbon was determined by applying 40, 80, and 120 lb per acre of carbon in bands which were 0.33, 0.67, and 1.0-inch wide. Narrower bands required more carbon for the same protection. A carbon band which was 1.0-inch wide provided adequate protection under greenhouse conditions. The 80 and 120 lb per acre rate of carbon provided only marginal protection. The type and rate of wetting agent used influenced the protection obtained. X-77, Surfactant-WK, and Rhodes' Spreader-Activator were used at rates of 0.3, 0.9, and 2.7% (v/v) to aid carbon suspension. All wetting agents reduced the protection when added at rates of 0.9 and 2.7%, but did not reduce protection when added at 0.3%. Rhodes' Spreader-Activator was less deleterious than the other two wetting agents tested. The soil moisture level at the time of carbon and herbicide application and the amount of overhead irrigation following application did not significantly affect the protection obtained. Therefore, these two factors should be manipulated to favor the crop during establishment. Field experiments were conducted to test the influence of the rate of activated carbon on its ability to inactivate herbicides and protect perennial ryegrass (Lolium perenne var. Linn L.), bluegrass (Poa pratensis var. Merion L.) and chewings fescue (Festuca rubra var. commutata Gaud.). Activated carbon was applied in a band 1.0-inch wide at 0, 150, and 300 lb per acre. Four herbicides-3-tert-butyl-5-chloro-6-methyluracil (terbacil), diuron, 2-chloro-4-ethylamino-6-isopropylamino-s-triazine (atrazine), and 2-chloro-4, 6-bis(ethylamino)-s-triazine (simazine) - were applied to all test species. Diuron had the greatest safety margin for the three species tested, but terbacil showed good selectivity on bluegrass, also. A minimum of 300 lb per acre of activated carbon was required for acceptable protection. Good weed control was obtained with all herbicide treatments. |
| Genre | Thesis/Dissertation |
| Topic | Herbicides -- Toxicology |
| Identifier | http://hdl.handle.net/1957/46127 |
