Pine Straw Harvesting Effects on Vadose-Zone Water Content of a Leadvale Silt Loam in Western Arkansas

Abstract

This study addresses concerns that harvesting marketable pine straw from forests may decrease timber productivity by allowing water to evaporate more quickly from the soil surface. Three harvesting schedules and a control treatment (no straw harvest) were replicated six times on 24 plots (0.18 ha each), and compared to determine harvesting effects on water content of the soil vadose zone in an established (16 yr) loblolly (Pinus taeda L.) plantation (3.0 × 1.5 m2 tree spacing). Pine straw harvesting tended to decrease volumetric soil water content (%) at depths below 20 cm, but the effect was significant (p < .05) only at the 50-cm depth in Weeks 3 and 4 (late June) of the study, when water content at this depth averaged 20.9% for soils where straw was harvested annually, and 30.2% for soils where the straw was never harvested (control). In soils where pine straw had been allowed to accumulate for at least a year after the previous harvest, average water content was not significantly different than in the control plots. Therefore, pine straw harvesting can potentially lengthen drought-stress periods for loblolly pine on some soils during the 1st yr after pine straw has been removed.