I have two large trees (spruce?) in the backyard that have quickly turned brown from the inside out, bottom to top. Is there anything I can do?
I think what you are seeing is the natural needle drop which occurs every fall and is no cause for concern. While conifers are referred to as ‘evergreen’ their needles don’t last forever. Spruce trees hold their needles for about 5-7 years while pine trees hold theirs for only 2-3 years before turning brown then dropping. This seasonal loss of needles occurs mainly on the inside of the tree as you are observing.
Fall needle drop is usually very noticeable on pines but may go unnoticed on spruce. However, if trees have experienced particular stress such as the drought we’ve experienced in Toronto this year, fall needle drop will be intensified. The browning on your trees may be more noticeable this year for this reason.
Be sure to keep watering your trees if rainfall is inadequate to ensure they go into winter with adequate water in their root system. Evergreens in particular are vulnerable to desiccation and winterburn.
If you’d like to read more about natural needle drop, the Morton Arboretum in the Chicago area has some good online information. Click here to reach their site.