Prescribed burning of endophyte-infected tall fescue plots: Effects on forage production, ergot-like alkaloid concentrations, and botanical composition

Abstract

Our objective was to evaluate the effects of early-spring prescribed fire on forage production and botanical composition in Kentucky 31 tall fescue plots. Treatments were applied in a completely randomized design with 10 plots per treatment. Treatments were (1) no burn (CON), (2) March mowed (MWD), (3) March burn (EBRN, early burn), and (4) April burn (LBRN, late burn). Beginning in May and repeated monthly until October, tall fescue tillers were hand clipped at ground level while walking an “X” pattern. In May of each year, tall fescue seedheads were counted in twelve 0.09-m2 quadrats per plot, and species frequencies were recorded. Species frequency was collected again in October. Tall fescue seedheads were reduced by 72% (P < 0.01) for LBRN. Spring forage accumulation was reduced (P < 0.01) by MWD, EBRN, and LBRN treatments, with EBRN and LBRN having a greater reduction (P = 0.03) than MWD. Nonfescue forage species frequency increased (P ≤ 0.01) in October for LBRN. Ergovaline concentration did not differ (P = 0.57) among treatments but differed (P = 0.01) by month, with a substantial increase in June compared with other months. Early-spring prescribed fire reduced tall fescue seedhead production; however, fire also reduced forage production. Removal of a portion of seedheads from tall fescue plots did not affect ergovaline concentration in plant samples. Thus, future research should evaluate ergot-like alkaloid concentrations in various plant parts from tall fescue subjected to seedhead control measures.