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Stark-Billings County |
Extension Spotlites
October 7, 2008
Fall Needle Drop in Conifers
During autumn, deciduous trees like green ash and linden change color and lose their leaves. This is normal and expected. It happens every year and people are used to it. When evergreen needles turn brown and die, it’s definitely unexpected, but not necessarily abnormal.
There are several species of evergreens or conifers that are grown in North Dakota. Pines and spruces are most common. Pines have relatively long needles (two to nine inches), which are held in clusters call fascicles. These needles live for two to seven years and then die and drop during the fall. These are the older needles toward the center of the tree. The needles that are going to drop start turning yellow as early as late August. By mid September these needles turn brown and begin falling from the tree.
Another common group of conifers are the spruces. These trees have shorter needles, about tree quarter to an inch long, and are attached to the stem individually, not in bundles. Spruce needles usually live longer than pine needles and may persist for up to 10 years. Just like pines, the spruce needles, which are older and more shaded, will turn color and drop during autumn.
Evergreen needles don’t last forever. Some needle loss toward the center of the tree during autumn is normal. Needle loss at other times of the year is not normal and may be due to an insect or fungal pest or the result of severe environmental stress.
For more information contact:
Kurt Froelich, Extension Agent
NDSU Extension Service
Stark-Billings County
1340 W. Villard St.
Dickinson ND 58601-4646
(701) 456-7665