Pine Needle Drop - Natural Occurance

Contrary to popular belief, evergreen foliage does not remain attached indefinitely. Older, inner needles discolor and drop-off after one to several years depending on the species involved.

Now that cooler weather has hit, we are seeing a lot of our pine trees with brown needles. In late summer and throughout the fall, many homeowners observe a discoloration of the needles on their evergreens and fear that some insect or disease has affected the plants. Do not be alarmed; this is a natural condition.

Evergreen shrubs and trees remain green throughout the year because they do not lose all of their foliage at one time. Usually needle drop goes unnoticed because new needles conceal the old, inside needles and foliage that has turned yellow and brown. Sometimes the drop occurs slowly, but on other occasions, many needles discolor and drop simultaneously. Most evergreens drop their needles in the fall, but some evergreens shed their needles in the spring or early summer. Each species of evergreen is different. Evergreens that normally shed one-year needles are arborvitae and white pine.

White pines are the most dramatically affected. This species commonly bears three years' needles in the summer and two in the winter. In October or November of some years, this species may have only one year of needles still attached. Matured white pine needles turn yellow throughout the tree. The tree will appear unhealthy when the yellowed needles outnumber green ones of the current season.

Australian and Scotch pine usually retain their needles for three years. Spruce and fir trees retain their needles for several years. Needle drop may not be visible unless one looks for it on the inner branches. Few needles turn yellow and drop in late spring or early summer of their third year.