Despite the name evergreen, these types of plants don’t hold onto their needles or leaves forever. They shed their older needles or leaves at some point in time. Different species shed at different times.
For instance, if you are fortunate enough to have the evergreen magnolia, the Southern magnolia (it is hardy in our area), then you might notice in the spring that the older leaves tend to drop off.
When pines begin to turn color and lose their older needles in the fall, it sometimes causes a bit of a panic. If you are not familiar with this yearly event, you might think that you are losing your tree.
Depending upon the species, pines hold their needles anywhere from three to five years. The most common pine in our area, the Eastern white pine, holds it needles for three years and sheds the 3-year-old needles in the fall. The Austrian pine is another common one in this area and holds its needles for four years.
During particularly stressful growing seasons, they may shed two years worth of needles, making the plant look extremely bare and causing considerable worry for the homeowner.
If you have one, then take a close look at your pine. Start at the tip of the branch and work your way back toward the trunk. If the needles are green toward the tip, you are in good shape. If they are brown, then you might have a problem and need to figure out the cause.
If the inner needles, closer to the trunk, are turning more of a yellow or golden yellow color, then the tree is likely OK and simply shedding the older needles.
Take a look at the ground under a pine tree and you will find the accumulation of many years of pine needles if the tree is older. This is not a bad sign and is quite normal.
Arborvitaes and other evergreens do the same thing. We just don’t tend to notice them as much. Again, if it’s the older needles, the plant is just doing its normal thing.
Some are concerned that the pine needles cause the soil pH to be more on the acid side. Research has shown that there is very little change in soil pH due to pine needles (oak leaves, as well).
It seems that needle drop is quite heavy this year, and it makes sense. If you remember back three years ago, we had an exceptionally wet spring and July, allowing for a great deal of plant growth. The more needles that develop in a year, the more needles that drop.
The term used for this is “physiological leaf drop,” and it happens every year, to some degree or another.
About the Author