Retained vegetation density of streamside management zones and stringers in southern intensively managed pine forests

• Stem density in overstory (hardwoods, pines) and midstory (pines) is lower in stringers than SMZs.
• Density of snags, logs and midstory pines did not differ between stringers and SMZs.
• Ground cover and understory hardwood cover did not differ between stringers and SMZs.
• Stringers augment SMZ contributions to green tree retention in intensively managed pine forest.

In the southern U.S. (hereafter, South), institutional forest owners engaged in forest certification programs often retain unharvested or less-intensively harvested vegetation when clearcut harvesting intensively managed pine (Pinus spp.) forests (IMPFs). As a result, IMPF landscapes consist of regenerating forests and associated retained streamside management zones (SMZs), stringers (buffer strips along ephemeral streams), and other forest types and structural classes. Although studies in the South have documented plant and animal communities associated with SMZs, there is a lack of information about stringers. To improve understanding of the potential for stringers to contribute to biodiversity-related management objectives, we characterized stem density and vegetation cover in SMZs and stringers associated with 60 IMPF management units (MUs) in the South Central Plains ecoregion of Arkansas and Louisiana, USA. Snag and log density, midstory pine density, understory deciduous cover, and ground cover were not statistically different in stringers and SMZs; however, overstory (pine and deciduous) and midstory (deciduous) tree density was significantly lower in stringers than in SMZs, and understory pine density was significantly greater in stringers.