through several mechanisms. Competition between weeds and cover crops will occur to varying degrees based on the vineyard environment and management. Allelopathic suppression of weeds has been observed upon decomposition of legume residues, such as clovers
Levi Fredrikson, Patricia A. Skinkis and Ed Peachey
Rye, wheat, and crimson clover were planted in separate pots outdoors in the fall of 1992 and 1993 Control pots had media without plants in them. There were 4 replications in 1992 and 9 in 1993. In early spring. the rye, wheat, and crimson clover were killed, using tillage in 1992 and glyphosate in 1993. In 1992. the residues were tilled into the media. In 1993, the residues were left on the surface. `Cardinal' strawberries, yellow nutsedge nutlets, crabgrass seeds, or bermudagrass rhizomes were planted into pots with the various residues, and also into the control pots. In July of 1992 and August-September of 1993, the weeds and strawberry plants were removed from the pots. Various growth measurements were taken on the plants. None of the tilled residues affected the growth of nutsedge or crabgrass, but tilled rye and wheat residues increased the growth of strawberry plants and decreased the growth of bermudagrass. None of the residues left on the surface significantly affected the growth of crabgrass. Clover residues suppressed nutsedge growth Both strawberry and bermudagrass growth was greatly reduced by all surface residues
Rebecca M. Tashiro, Joseph H. Bouton and Wayne A. Parrott
White clover ( Trifolium repens L.) is an annual or short-lived perennial found throughout temperate regions of the world ( Gibson and Cope, 1985 ). Originally native to the Mediterranean ( Ellison et al., 2006 ), white clover grows in a wide range
Michelle Hadawi-Broeske and Helen C. Harrison
Renewed interest in soil conservation over the past decade has led to greater research efforts in the area of living mulch cropping systems. However, crop/mulch competition continues to present challenges. The objective of this study was to determine what effect two types of chemical growth suppressants (Mycogen 6121—an herbicidal soap, and Royal Slo-grow—a soil plant growth regulator) had on the water-use efficiency, nutrient use, and soil-shading ability of two annual living mulches, ryegrass (Lolium multiflorum) and crimson clover (Trifolium incarnatum). Two greenhouse experiments were performed in sand culture using a modified Hoagland's soap, one rate of growth regulator, and a mechanical treatment of mowing. Significant differences in nutrient use and soil-shading ability were obtained. The second experiment (69 days) replicated the ryegrass treatments less one rate of soap and included the legume crimson clover with one rate of soap and one rate of growth regulator. Results from both experiments will be discussed.
Lin Wu and Zhang Z. Huang
Substantial difference of selenium tolerance was found between the tall fescue (Festuca arundinacea Schreb.) and white clover (Trifolium rapens L.) An inverse relationship between Se accumulation and Se tolerance suggests an exclusion mechanism that restricts Se uptake by the plant with greater Se tolerance. A positive relationship between the increase of protein Se concentration and growth inhibition in the plants suggests that assimilation of Se into protein is responsible for the reducing Se toxicity at the protein level. No evidence of a Se exclusion mechanism which exclude Se from incorporating into protein plays any major role of Se tolerance in this two species.
B. Scully, R. Provvidenti, D.E. Halseth and D.H. Wallace
Ted S. Kornecki and Francisco J. Arriaga
is under no-till production ( CTIC, 2004 ). A limiting factor is the lack of equipment (rollers/crimpers) needed to manage tall cover crops such as cereal winter rye ( Secale cereale L.) and winter crimson clover ( Trifolium incarnatum L.) in flat
Alyssa R. Tarrant, Daniel C. Brainard and Zachary D. Hayden
not possess all of these desired characteristics, various species and plant functional groups exhibit distinctive strengths and weaknesses influencing their suitability as a living mulch. For example, clovers are commonly used legume living mulch