Herbicides
Brush Control in Pine Stands (Pine Release)
When establishing pine plantations after harvesting hardwood or mixed pine-hardwood stands, vigorous sprouts from established hardwood root systems may overtop planted pines. Since pines are not tolerant of shade, this leads to reduced pine survival and growth rates. Controlling competing hardwoods at the time of site preparation is the best approach (see Preparing for Planting), but new “selective herbicides” can be broadcast by helicopter or ground spray machinery over-the-top of planted pines to control competing hardwoods without significant pine injury (pine release). The selective herbicide imazapyr (Arsenal® AC) is most widely used for this purpose, but one must consult supplemental labeling for the release of the slash and loblolly pines (please see below the table). Another approach is to use non-selective herbicides such as glyphosate or triclopyr as a directed spray to control individual hardwoods.