In the fall it is common to see that your evergreens have needles turning color, especially on the inside of the canopy. The needles of conifers have a life span that varies from one, to several years depending on the tree species. The interior needles change to a yellow or orange color before dropping off the tree. The needle drop is triggered by the cooler fall weather just as deciduous trees lose their leaves each Fall, evergreens drop the older needles to replace them with new ones ready to produce energy for the tree. It can be gradual or rapid depending on the specific year. Drought stress from dry hot summer or fall conditions can cause heavier needle shed such as we are seeing in the Fall of 2017.
Key Points
- Seasonal needle drop is part of the normal growth cycle of a conifer.
- Appears in the fall and can be gradual or rapid.
- Check that current season’s growth is healthy.
- Times of drought can result in an increase of needle drop.
- Deep watering of mature trees can help them retain more needles, longer as well as help increase the rate of new growth. Check out the TreeIB watering system
Tree Damage
- Although sometimes alarming, there is no damage to the tree as long as it is only the older interior growth.
- Part of the normal growth cycle of a tree.
Control Measures
- Check your trees regularly to see if the current season’s growth is wilting or discoloured which can indicate a more serious problem.
- All trees should receive sufficient supplemental water throughout drought periods to help the tree retain as many needles as possible.
- If the damage is at the tips of the branches or at the top of the tree, you may have a larger problem and you should contact your Arborist for an assessment
