United States Department of Agriculture
Yellow-poplar seed lots can be upgraded considerably by dewinging in a debearder and then cleaning and separating the seeds into four specific-gravity fractions with a fractionating aspirator or a gravity separator. By this process, lots with an original soundness of 6 to 10 percent were upgraded to between 60 and 65 percent full seeds.
An experimental technique using water extraction for evaluation of the content of ployethylene glycol of molecular weight 1,000 in wood where the ovendry weight of the untreated wood is not available was shown to be applicable for PEG-treated black oak and yellow-poplar.
Ten years after a Southern Appalachian hardwood stand was clearcut, numbers of stems of desirable species appear adequate to restock the area. Yellow-poplar will dominate on the better sites. Some problems are anticipated from grapevines, black locust thickets, and red maple clumps.
Four years after planting in oak clearcuttings, 1-1 white ash transplants had the best survival and growth of seven hardwood species. Other species tests were yellow-poplar, sugar maple, red maple, northern red oak, and American basswood. The relatively high success of white ash makes it the safest selection for Upper Mississippi Valley clearcut interplantings....