Identifying the root collar on forest tree seedlings

This paper offers practical guidelines on how to identify the root collar of species commonly grown in Ontario forest tree nurseries. These guidelines would also be applicable to naturally-regenerated seedlings. Difficulties associated with locating the root collar on transplanted stock are also addressed. Colour differences on the stem are not reliable for locating the root collar; stem colouration can vary according to surface soil level and planting depth. The paper distinguishes among three parameters: apparent root collar (ARC), root collar, and ground-line diameter. Key words: caliper, cotyledon, hypocotyl

Responses of Vegetation and Deer Forage Following Application of Hexazinone

Vegetation responses were studied on a loblolly pine (Pinus taeda) plantation that had received intensive mechanical site preparation and hexazinone (1 lb/ac a.i.) for herbaceous weed control. Vegetation on plots treated by a broadcast application of granular hexazinone (Pronone® 5G) was compared to vegetation on plots that received a banded (top of bed only) application of liquid hexazinone (Velpar® L). Total plant biomass was significantly greater (P < 0.10) on control plots (2,512 lb/ac, dry wt) than on broadcast (1,089 lb/ac) or banded plots (1,481 lb/ac) in September of the first growing season, but differences disappeared by the end of the second growing season. Total number of plant species on control plots (105) and banded-treated plots (97) was similar, but fewer plant species (60) were found on broadcast-treated plots the first year. At the end of the second growing season, the number of plant species was similar on all treatments. White-tailed deer (Odocoileus virginianus)forage was significantly greater on control plots (1,481 lb/ac) than on broadcast (393 lb/ac) and banded plots (534 lb/ac) in September of the first year's growth, but there were no differences after the second growing season. Pine seedling survival was lower on herbicide treated plots, but seedling height and ground line diameter were greater on herbicide treated plots. South. J. Appl. For. 11(4):176-180.

Effects of Site Preparation on Soil Physical Properties, Growth of Loblolly Pine, and Competing Vegetation

Competing vegetation, seedling survival, and growth of loblolly pine (Pinus taeda L.) were evaluated one year following four site-preparation techniques in north Louisiana. The treatments were chop and burn, windrow, fuelwood harvest, and fuelwood harvest followed by a herbicide. Physicalsoil properties were evaluated before and after treatment application. The study was designed as a randomized complete block and was installed on a Gore silt loam (Vertic Paleudalf) soil. Windrowing significantly increased surface bulk densities. Fuelwood had significantly higher bulk densityvalues for subsurface samples. In comparisons among treatments, surface bulk densities for the windrow treatment were significantly higher than both of the fuelwood treatments. The fuelwood treatment was significantly higher in competing vegetation while the fuelwood followed by a herbicidetreatment was significantly lowest. The fuelwood followed by a herbicide ranked significantly higher in seedling height, ground line diameter, and volume. Seedling growth was inversely related to competing vegetation dry weight. There were no significant differences among treatments in seedlingsurvival. South. J. Appl. For. 11(2):83-86.

Effects of Ripping and Herbicide Site Preparation Treatments on Loblolly Pine Seedling Growth and Survival

Herbicide (1 lb ai/acre hexazinone as Velpar® L) and mechanical (ripping) site preparation treatments increased height and diameter of loblolly pine (Pinus taeda L.) seedlings planted on a Ouachita Mountain site in southeastern Oklahoma. Total height after two growing seasons was increased approximately 10% by ripping, 23% by the herbicide treatment, and 49% by the combined herbicide and ripping treatment, as compared with the check treatment. Ground-line diameter was increased 20%, 55%, and 83% respectively by these treatments. Reduction of competing vegetation and increased soil moisture were related to site preparation treatments. The combined ripping and herbicide treatment was the most effective treatment in conserving soil water and in reduction of competing biomass. Competing vegetation biomass was reduced 75% in the first year by the combined ripping-herbicide treatment, and a substantial reduction in competing biomass was still evident at the end of the second growing season. South. J. Appl. For. 10:253-257, Nov. 1986.