Low Intensity Harvest Management of Reed Canarygrass

High K grass forage increases risk of animal metabolic disorders, and forage management of perennial grass grown under K‐limiting soil conditions needs further study. Our objective was to evaluate forage nutritive value, yield, and stand persistence of reed canarygrass ( Phalaris arundinaceae L.) under two‐harvest management and low availability of soil K. Three N and three K fertilizer treatments were applied to reed canarygrass for 5 yr at two sites in central New York state with Niagara silt loam (fine‐silty, mixed, active, mesic Aeric Epiqualfs) and Williamson silt loam (coarse‐silty, mixed, active, mesic Typic Fragiudepts) soil types. Reed canarygrass persisted under all treatments throughout the experiment, although K deficiency symptoms appeared in the high N, low K fertilizer combination. At the high N fertilizer rate, dry matter (DM) yield increased linearly ( P < 0.05) with increased K fertilizer rate, while K fertilizer did not influence yield in the absence of N fertilizer. Recovery of K fertilizer was low and increased linearly ( P < 0.05) with increased N fertilizer rate from 6 to 42%. Soil test K increased to 59.9 mg kg −1 with no N fertilization and decreased to 34.9 mg kg −1 with 224 kg N ha −1 . Under high N fertilization with no K fertilization, grass forage K concentration averaged <12 g kg −1 in the spring and <8 g kg −1 in the fall. Sufficient yields of grass forage with reasonable quality and low concentrations of K were possible through high N, low K fertility management in a two‐harvest system.