DON’T PANIC: Nothing’s wrong, and they’re not all dying in unison, I promise. Though we commonly call them “evergreens,” conifers such as pine, arborvitae, spruce and Hinoki cypress (above) lighten their load of old needles in late summer and fall, with a show of yellowing or browning that can scare a gardener at first.This phenomenon should not be confused with browning at the tips or overall yellowing or browning that can happen at other times—such as from winter desiccation; from the effects of roadside salts; from pests and diseases (including diplodia tip blight in some pines or phomopsis in spruce and non-resistant junipers); or from drought. (See what road-salt damage and winterburn look like by comparison in these photos.)
The browning I noticed in late July on my Eastern red cedar in the front yard (Juniperus virginiana) is suddenly showing up as gold or rusty-brown or a progression from one to the other on many other conifer species. The Eastern white pines (Pinus strobus), above, with their long needles, are always the most dramatic, turning what looks like mostly gold. Hard to believe the plant will be OK.
But in fact needle-drop is a normal part of the life cycle, though the rate varies by species, and can also accelerate if environmental stresses like dry conditions or pest infestation have affected the tree or shrubs in a given season.