Around the Pacific Northwest, we have a lot of evergreen trees ends this typically around Bothell Washington. Of course, anyone can have an evergreen tree from the Canadian border to Southern Oregon, but we specifically work within the Snohomish County area with an emphasis on Bothell, Redmond, and Millcreek.
But, getting back to the topic, what happens if you notice your evergreen tree starting to turn brown from the bottom up?
This usually means it simply needs water. Of course, any tree or bush that gets brittle and dry will need more water. In drought-like conditions, evergreens have trouble getting enough water to all of their needles and so they kill off the bottom needles to hydrate the rest of the tree. If the tree soil is dry you want to continue watering it throughout the year and apply mulch to seal in the moisture.
This also could be pest or disease. Evergreen trees can attract a lot of pests such as the pine beetle or getting a disease that leaves bulges on the branches and sap seeping from the trunk. You want to look on your evergreen for any small holes or Sodus which means insect infestation. For disease, look for large canker’s leaking white sap and if necessary, have a tree expert take a look to diagnose and determine the best course of action.
But, this also just could be a natural defense mechanism of the tree. Evergreens will naturally kill out the older needles as part of their growing cycle. When higher needles branch out lower ones can get blocked from sunlight so they will simply fall off and die. As long as your soil is moist and you don’t see any infection, the tree is still in good shape.