Date of Graduation

Fall 2018


Master of Science in Plant Science (Agriculture)


College of Agriculture

Committee Chair

Sarah Lancaster


cover crop, cover crop mixtures, herbicide resistance, allelopathy, common waterhemp, large crabgrass

Subject Categories

Agriculture | Agronomy and Crop Sciences | Weed Science


Cover cropping systems are widely used in crop production systems to prevent erosion, improve soil health, and suppress weeds. Common cover cropping systems include combinations of cereal rye (Secale cereale L.), Brassica species, legumes, and other winter annual species. Three cover crop mixtures (cereal rye alone, cereal rye plus winter pea, and cereal rye plus winter pea plus radish) were applied using three methods (fresh residue, dried leached residue, and leachate) to common waterhemp (Amaranthus tuberculatus var. rudis) and large crabgrass [Digitaria sanguinalis (L.) Scop.]. The experiment was conducted once in a greenhouse and once in a growth chamber Significant interactions (α=0.05) were observed in the greenhouse study between treatment and days after planting (DAP) for emergence, height, and leaf count for common waterhemp. In addition, fresh cover crop residues suppressed common waterhemp emergence relative to dried leached residue. The interaction of treatment and DAP was also significant for large crabgrass emergence. In the growth chamber study, common waterhemp data were inclusive due to poor emergence. No significance was observed with the large crabgrass, but trends suggest that fresh residue was more effective than other applications. In conclusion, the results of this study suggest that cover crop mixtures did not influence weed response, but data suggest that allelopathy had an important contribution in both environments.


© Alyssa D. Travlos

Open Access