EFFECT OF SOIL TYPE AND LIMING RATES ON ROTATIONAL FORAGE CROP INJURYFOLLOWING METSULFURON METHYL

Solution pH from 6.0 to 8.0 did not affect the germination of Italian ryegrass, 'Pensacola bahiagrass,' or common bermudagrass grown in petr i dishes in growth chambers. Seeding intervals following metsulfuron m ethyl application varied from species to species and between soil type s. Greenhouse studies indicated that in an Okolona silty clay, common bermudagrass should not be planted until 12 wk after metsulfuron methy l application. Italian ryegrass showed no metsulfuron methyl injury at the 6-wk sampling date when no lime was added, indicating reseeding w as feasible at this time; however, a 12-wk time interval was not suffi cient when lime was applied. Pensacola bahiagrass was injured when res eeded at 12 wk, regardless of liming rate. In a Prentiss fine sandy lo am soil, common bermudagrass could be reseeded 12 wk after application when no lime was added, but not when lime was added. Italian ryegrass and Pensacola bahiagrass should not be reseeded for at least 12 wk, r egardless of lime rate. Field experiments, where metsulfuron methyl wa s applied to the field and seeding was carried out in the greenhouse, indicated on the Okolona silty clay that common bermudagrass reseeding could occur at all liming rates after 3 wk, and Italian ryegrass and Pensacola bahiagrass after 6 wk. In the Prentiss fine sandy loam, comm on bermudagrass reseeding could occur at 3 wk, regardless of lime rate . Italian ryegrass emergence was not affected when reseeded immediatel y after metsulfuron methyl application, but height was reduced for lon ger periods, and increased lime rate lengthened this interval. Pensaco la bahiagrass reseeding was feasible at 3 wk. Nomenclature: Metsulfuro n methyl, 2-[[[[(4-methoxy-6-methyl-1, 3,5-triazin-2-yl)amino]carbonyl ]amino] sulfonyl]benzoic acid; bahiagrass, Paspalum notatum var. saura e Parodi, 'Pensacola' #(3) PASNS; bermudagrass, Cynodon dactylon (L.) Pers. 'Common' # CYNDA; Italian ryegrass, Lolium multiflorum Lam. 'Mar shall' # LOLMU.