Master of Science (MS)


Plant, Enviromental and Soil Sciences

Document Type



Atrazine, one of the most widely used herbicides in the United States, is commonly applied to southern lawn grasses to reduce weed encroachment. According to the EPA, atrazine is also one of the most frequently identified herbicidal compounds in surface and ground waters. Given the increased management intensity of home lawns in Louisiana, coupled with urban sprawl and high rainfall has led to a higher potential for movement of atrazine into surface waters during runoff events. Experiments were conducted at the LSU AgCenter Burden Botanic Gardens on centipedegrass (Eremochloa ophiuroides) at a 5% slope to evaluate the effect of atrazine formulation and post application management on atrazine movement. Atrazine was applied as a granular or liquid and either incorporated with 1.25 cm of irrigation or not incorporated. Four days post-atrazine application, treatment combinations were subjected to rainfall simulation at 5.5 cm hr-1 for 30 min of surface runoff. All herbicides exhibited the highest loss at 4 DAT followed by declines in losses with subsequent surface runoff events. In both experimental runs, granular atrazine resulted in lower total atrazine runoff losses compared to liquid applied atrazine. However, in the second experimental run irrigation reduced liquid applied atrazine 36% from unincorporated liquid applied atrazine. When simazine was compared to atrazine following the same application parameters, simazine resulted in >90% total reduction in herbicide losses compared to atrazine. Based on this research atrazine losses from surface runoff can be mediated through application of granular applications, irrigation when liquid atrazine is applied, or selection of simazine for area prone to frequent surface runoff.



Document Availability at the Time of Submission

Release the entire work immediately for access worldwide.

Committee Chair

Beasley, Jeffrey S.