SOIL-TEMPERATURE, SOIL-MOISTURE, WEED-CONTROL, AND TOMATO (LYCOPERSICON-ESCULENTUM) RESPONSE TO MULCHING

Shredded newspaper (2.5, 7.6, 12.7, and 17.8 cm depth), chopped newspa per (2.5 and 7.6 cm), wheat straw (15.2 cm), black plastic, and plasti c landscape fabric were evaluated during 1993 and 1994 in West Virgini a for their effect on soil temperature, soil moisture, weed control, a nd yield in tomato. Shredded newspaper and wheat straw applied at 0, 2 , 4, or 6 weeks after transplanting (WAT) and napropamide (2.1 kg ai/h a) plus metribuzin (0.28 kg ai/ha) applied at transplanting were evalu ated during 1992 and 1993 in North Carolina for effect on weed control and tomato yield, Results from West Virginia indicated that shredded (7.6 cm) and chopped (7.6 cm) newspaper conserved moisture similar to higher application rates of the shredded material. Higher newspaper mu lching rates reduced soil temperature compared to black plastic and ba re ground. Chopped newspaper controlled weeds more consistently than o ther treatments, At least 7.6 cm of chopped newspaper mulch was requir ed to control weeds at least 90%. Wheat straw was not as effective in controlling weeds as 7.6 cm or greater of newspaper mulch. Chopped new spaper provided higher tomato yields than shredded newspaper applied a t the same rates. Mulches applied at 0, 2, or 4 WAT resulted in weed c ontrol similar to the chemical treatment. In North Carolina, mulches a pplied 2 or 4 WAT resulted in tomato yields similar to the chemical tr eatment. Shredded and chopped newspaper have potential as a mulching m aterial but may vary in effect in different environments and vegetable crops.