Survey of Orchardgrass Persistence in the Mid-Atlantic States

摘要

Orchardgrass (Dactylis glomerata L.) is an important forage species for hay production and grazing in the Mid-Atlantic region of the US. Recently, forage growers in this region have observed a marked decline in orchardgrass stand persistence. In 2014,a survey was conducted using 53 orchardgrass fields across Virginia, Pennsylvania, Maryland, and West Virginia to evaluate potential causal factors for reduced stand persistence. Relationships among soil fertility, management practices, disease, and climate were related to stand persistence ratings and biomass of orchardgrass hay fields. Soil samples were collected for fertility analysis, standing biomass was harvested and analyzed for mineral content, and tillers were evaluated for leaf disease. An information theoretic approach to multi-model inference was used to determine the most important variables that explained persistence. Soil P, soil organic matter, manure application, planting year, and historic average maximum temperature were most closely related to perceived orchardgrass persistence. Soil fertility does not appear to be the main driver of orchardgrass persistence problems in this region as mean soil test pH, P, and K were found to be adequate relative to critical values. We suggest other variables, such as warmer climate or possibly cutting height management, may be playing a bigger role in explaining reduced orchardgrass persistence.