HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Anderson, R. L. Articles by Humburg, N. E. Search for Related Content PubMed Articles by Anderson, R. L. Articles by Humburg, N. E. Agricola Articles by Anderson, R. L. Articles by Humburg, N. E.

Field Duration of Chlorsulfuron Bioactivity in the Central Great Plains¹

ABSTRACT

The duration of chlorsulfuron {2-chloro-N [(4-methoxy-6-methyl-1,3,5-triazin-2-yl)aminocarbonyl]benzenesulfonamide} bioactivity in Central Great Plains soils was determined by measuring the influence of several environmental factors on chlorsulfuron degradation. Chlorsulfuron was applied at 35 and 70 g ha^–1 to four soils: Platner sandy loam and Weld (Aridic Paleustolls) loam at Akron, CO; Roxbury (Cumulic Haplustoll) silt loam at Jetmore, KS; and Rosebud (Aridic Argiustolls) sandy loam at Chugwater, WY. Soil pH, organic matter level, number of precipitation events >0.25 cm, and leaching were the major environmental factors influencing chlorsulfuron duration of bioactivity. A chlorsulfuron rate x soil x year interaction occurred, but this interaction was not consistent over all soils. A model developed for predicting chlorsulfuron duration of bioactivity would be more accurate if designed for soils with similar organic matter levels, as organic matter level influenced duration of bioactivity and leaching of chlorsulfuron. Chlorsulfuron leaching was also affected by soil type and year of study. In greenhouse bioassay studies, sunflower (Helianthus annuus L.) did not differ from corn (Zea mays L.) in sensitivity to chlorsulfuron residues in soil.

Key Words: soil pH • leaching • model • bioassay • pesticides

¹ Contribution from the Agric. Res. Serv., USDA, Mountain States Area.

² Research agronomist, USDA, Akron, CO 80720; and private consultant, Cheyenne, WY 82009, respectively.

Received for publication October 14, 1986.