The pre-emergence herbicidal activities and behaviours of turf herbicides in soil

Abstract

The writers tested to clarify the herbicidal activities and behaviours of turf herbicides in soil.
And the following results were obtained.
1.The pre-emergence herbicidal activities to seven graminious plants [Alopecurus aequalis Sobol. var. Amurensis, Poa anna, Agrostis palustris, Echinochloa Crus-galli Bepuv. flumentaceae Trin., Digitaria cliaris (Retz. Koehler. Setaria viridis (L.) Beauv.]
Pendimethalin and benefin at 2.5-5 ppm, atrazine and simazine at 5-10 ppm, propyzamide, napropamid and asulum at 10-20ppm, and others at more than 20 ppm were effective on graminious plants respectively.
Atrazine and asulum were not effective on all graminious plants tested, so these herbicides were effective on some plants at low concentration, but on others at higher concentrations.
2. The pre-emergence herbicidal activities to six broad-leaved plants [Kummerovia stiata (Thunb.) Schindl., Chenopodium serotinum L., Daucus carota L., Raphanus sativa L., Amaranthus lividus L., Capsella bursapastoris (L.) Medik.]
Atrazine, simazine, mecoprop and triclopyr at 5 - 10 ppm, pendimethalin and benefin at 10 - 20 ppm were effective respectively.
Simazine, atrazine, mecoprop and triclopyr were not effective on all plants.
3. The leachings of the herbicides in the clayish loam soil.
Nitrofen, simazine, MK-616 and benefin were leached to a depth of 0-1cm in the soil. Terbutol, pendimethalin and chlothalmethyl were leached to a depth of 2-3cm in the soil. Siduron, napropamid, propyzamide, Orthobencard and atrazine wereleached to a depth of 2-3 cm in the soil. Triclopyr, mecoprop and bensulide wereleached to a depth of 4-5 cm in the soil. And asulum was leached to a depth of 8 cm in the soil.
4. The residues of the herbicides in the clayish loam soil.
Mecoprop, triclopyr and nitrofen were effective for about 30 days in the soil. Atrazine and simazine were effective for about 50 days. Bensulide, napropamaid, terbutol, chlorthal-methyl, benefin and pendimethalin were effective for more than 60 days in the soil.
5.The lateral movements of the herbicides on the surface of the clayish loam soil.
Simazine, nitrofen and chlorthalmethyl spread in a narrow zone, but asulum expanded in large area on the soil surface.