Fertilization Effects on Yield and N Concentration of Midland Bermudagrass1

Abstract

AbstractA high yielding summer forage grass capable of with standing high temperatures and low moisture is needed in the northeastern U. S. ‘Midland’ bermudagrass( Cynodon dactylon (L.) Pers.) would meet these requirements, but production and management methods for the northeast need to be investigated.Studies were conducted over 3 years at two locations in West Virginia to determine the effects of N and K rates on yields and N recovery of ‘Midland’ bermudagrass. Treatments consisted of factorial combinations of zero, 112, 224, and 448 kg of N and K/ha. Herbage was harvested two or three times at both locations each year, depending on the growing season. Herbage yield and N concentration of the herbage increased and percent recovery of the applied N decreased as N application rates increased. Oven‐dried forage yields reached 19,000 kg/ha when N was applied at 448 kg/ha. Yield, N concentration of forage, and percent N recovery varied in response to K application with K having little overall effect. Weed encroachment was enhanced by N application at one location, but not at the other location. Temperatures as low as −29 C were recorded with no apparent winter killing.Soil pH decreased slightly with N application at one location, but not at the other. Available soil K correlated positively with K application rates and negatively with N application rates. Available soil Mg at both locations and available Ca at one location were decreased as N rates increased. Available soil Mg was decreased when K was applied at the zero N level, but otherwise, it was unaffected by K application.These studies indicate that while N is necessary for maximizing herbage yield of ‘Midland’ bermudagrass, other factors such as location and soil type are important in determining persistence and longevity. Also, additional nutrients, such as Mg, need to be considered as N levels are increased.