ABSTRACT

A field study was initiated in spring, 1992 to evaluate the effects of surface-applied noncomposted organic waste, (newsprint, wood products, yard waste, and gin trash), nitrogen (N) source to adjust C:N ratios, and time of organic waste application on seed cotton (Gossypium hirsutum L.) yield, growth, maturity, and weed control. The soil was a Cahaba-Wickham-Bassfield sandy loam (Typic Hapludult). Treatments included organic wastes, N source, and time of application as whole plots, with herbicide application methods as sub-plots. Organic wastes used as soil amendments reduced seed cotton yields, particularly newsprint. The yield reductions were not as great when broiler litter was used to adjust C:N ratios compared to adjustment with NH₄NO₃. Newsprint treatments reduced large crabgrass [Digitaria sanguinalis (L.) Scop.] seedling counts on an average of 65- to 70%. Organic wastes did not have any effect on efficacy of pre- or post-applied herbicidal control of grasses and broadleaf weeds in the cotton. Results also suggest that 4 to 6 weeks are required for biological stabilization of the newsprint decomposition. However, this requirement may change with repeated applications of newsprint.