Surface soil root distribution and possible interaction with site factors in a young longleaf pine standThis article is part of a larger document. View the larger document here.
Interaction between soil bulk density and low soil water content may create root growth-limiting soil strengths. In a Louisiana longleaf pine (Pinus palustris Mill.) stand, soil strength at the zero- to 20.0-cm depth was assessed in response to no fire or biennial fires in May. At the 5.0- to 20.0-cm depth, one-half of the measurements were characterized by root growth-limiting soil strengths regardless of fire history. Where soil strengths were root growth limiting, pine fine root biomass was about 24 percent lower than where soil strengths were not root growth limiting. Correlation between soil strength and pine fine root biomass was only observed where samples were collected distal to the longleaf pine trees, where soil strengths were high, and where biennial fire was applied. Further research is needed to determine whether repeated fire interacts with the relationship between soil strength and longleaf pine root growth on the west Gulf Coastal Plain.