reduced root growth and may not produce well in late summer and fall, especially in drier years. Fields that were cut for hay or have been rotationally grazed through the early season are the best choices for stockpiling. Pastures containing heavy growth of summer annual grasses such as crabgrass or foxtail should be avoided as the summer annual grass will utilize most available soil moisture and nitrogen. Avoid wet sites and low lying fields to minimize mud problems.
Quality of stockpiled pasture can be significantly increased by starting the stockpile growth from a uniform three to four inch residual height. Accumulating pasture growth with seedheads and dead leaves results in a lower quality stockpile and reduced fall growth rate. Presence of broadleaf weeds also reduces quality and growth rate. Heavy infestations can also reduce utilization in the winter. To avoid these problems, the pasture should be clipped or heavily grazed prior to the beginning of the stockpiling period. Clipped or grazed paddocks usually respond to N-fertilization with increased tillering. If significant manure accumulation is present after spring and summer grazing, harrowing the pasture helps produce more uniform fall growth.
TIMING TO BEGIN STOCKPILING
Having enough late season growing period to allow good yields but not too long to allow deterioration of feed quality is critical. We estimate that the maximum per acre yield is achieved with about 75 days of growth in the late summer-fall growing season. Stockpiling longer than this will not result in any more stored feed per acre but will result in lower quality forage. To determine when to begin stockpiling pasture, estimate your last day of active growth in the fall and back up 75 days. For example, we consider November 1 to be the end of our growing season, so we target August 15 as the beginning of the stockpiling season. A shorter fall stockpiling period will produce higher quality forage but at the cost of reduced yield.