needle discoloration of Yew - Ask Extension
We have three mature Yews that began to discolor this spring. They dropped the orange to yellow needles, and two of the bushes began to new growth. ...
Knowledgebase
needle discoloration of Yew #661451
Asked July 08, 2020, 12:53 PM EDT
We have three mature Yews that began to discolor this spring. They dropped the orange to yellow needles, and two of the bushes began to new growth. However, there are still areas where the needles are nearly striped yellow-green. I'm wondering if this is a sign of root mold, change in acidity, insects, or nutrient depletion. One additional detail is that the bushes are planted next to a cedar hot tub that gets drained from time to time (not directly on the roots). And in general, nothing has changed this year about its surroundings except for a late freeze in Boulder.
Denver County Colorado
Expert Response
Without evidence of an insect or disease, we have been seeing the same type of symptoms on numerous evergreen trees and shrubs this season. It is attributable to the very cold weather we experienced last fall as well as the hard freeze in April. With the warm weather, evergreens began to come out of dormancy and de-hardened and then were hit when the cold struck. Continue to irrigate, we do recommend watering with more water by hand. Trees and shrubs in this area need more water than the sprinklers can provide. Here is a fact sheet on care of mature trees: https://cmg.extension.colostate.edu/Gardennotes/657.pdf
We do not recommend fertilizing while the trees are stressed, it can make things worse. Here is a fact sheet that talks more about this: https://planttalk.colostate.edu/topics/weeds-cultural-problems/2129-winter-desiccation-evergreens/
We do not recommend fertilizing while the trees are stressed, it can make things worse. Here is a fact sheet that talks more about this: https://planttalk.colostate.edu/topics/weeds-cultural-problems/2129-winter-desiccation-evergreens/
