LAUSR

Abstract Management aimed at regenerating softwoods and hardwoods in the same stand (i.e., a mixedwood) has some appeal in the pine-hardwood forests of the southern United States. We revisited a group selection experiment installed in 1991 to evaluate the influence of gap size and site preparation treatments on a pine-hardwood stand in Louisiana, USA. Experimental treatments included a factorial combination of three group opening sizes (0.1, 0.25, 0.4 ha) and three methods of site preparation (chemical, mechanical, untreated) in the harvest gaps. Specifically, we tested two hypotheses: 1) regeneration of shade-intolerant tree species increased with gap size and the addition of site preparation and 2) if this site preparation decreased the regeneration of species that are more tolerant of shade and reliant on advance reproduction. In 2016, the density and basal area of the shade-intolerant loblolly pine (Pinus taeda), shortleaf pine (Pinus echinata), and sweetgum (Liquidambar styraciflua) increased with increasing gap size (P