Yellowing Evergreens and Pine Trees

yellowing needles on Scotch Austrian pines

Scotch/Austrian Pine with normal needle yellowing

Every year, beginning in August and continuing into the fall, some clients become concerned that their Evergreen trees are yellowing or browning to varying degrees. Many think their trees are dying.

ALLOW US TO EXPLAIN THIS SITUATION…..

‘Interior Yellowing’ of Evergreens or Pines is a common and normal occurrence. By ‘interior yellowing’ we mean the inner-most needles closest to the trunk or base of the limbs. As long as the outer portions of the trees are green, the trees are fine. If entire limbs are dying all the way out and into this year’s growth, that is a different story. Evergreen trees can only sustain four, five, or maybe six years of annual growth at a time.

Once every few years however, moderate to heavy shedding of interior needles will occur. Interior needles will turn yellow and fall to the ground as the tree feels the need to shed its excess growth, to keep itself as strong as it can to survive the winter, and prepare for next spring’s new growth. The inner needles cannot absorb sunlight as well, so they do not benefit the tree as much. So, they become weak and are discarded. While this situation may occur to a minor extent every year, once every 3 to 5 years it may be excessive.

White Pine Needles on our owner's driveway - looks scary but not a problem

White Pine Needles on our owner’s driveway – looks scary but not a problem

You will notice that any mature Evergreen tree you look at never has any live growth in its interior. These trees are barren inside. This is because they have gone through this normal shedding process so many times before.

Now, if inner browning is so excessive that your tree is only retaining two or three years of growth, then additional factors may be at play. If trees are stressed due to additional situations such as insects, fungus, drought, clay soils, planting at the top of a burm or over-watering due to sprinkler systems activating every two or three days, this situation could be accentuated. Again, this is why keeping trees strong through Root Fertilization is so important.

So, hang in there! They may look a little scary right now but the fall rains and winter winds and snows will knock the yellow and brown needles to the ground. Your trees will look much better this coming spring!