Strong and sturdy spruce trees and pines grow into towering staples of our home’s landscape. Non-surprisingly so, most homeowners wouldn’t think twice that anything could harm these robust beauties, who provide us year long color, privacy, and shade. But nature has teeny tricks up it’s sleeve in the form of pests capable of bringing down the all mighty evergreen. However with a mindful eye and our expert tips, these problems can be remedied, or better yet, prevented so you can enjoy healthy spruces and pines.
How to Determine Pest Damage in Spruce Trees and Pines
Most damaging insects prefer injured, stressed, or weak trees. This often describes many of the pines growing in an urban environment. Keep a look out for the following symptoms.
- Beetles 3-7 mm in length.
- Small, yellow gummy-shaped sap formations, called pitch tubes.
- Fine, powdery red-brown dust and round holes located on tree bark
- Foliage that changes to a dull green, then yellow and finally a reddish brown.
Common Pests That Affect Spruce Trees & Pines
So what’s causing the changes in your trees? You may have Pine Bark Beetles, Borers, Zimmerman Pine Moths, or Pine Weevils.
Preventative Treatment for Spruce Tree and Pine Pests
You should consider preventative measures around October 1st and/or April 1st. A Systemic Drench such as Bio Advanced Tree and Shrub Protection or Optrol should be repeated every 6-12 months. These insecticides can be applied to the soil to kill boring beetles. However these materials will not be effective on dying trees which are unable to take up material from the soil. This is why it is recommended that systemic drenches are more helpful for preventative measures for protecting apparently healthy evergreens, or applied to evergreens being planted after dead trees have been removed.
Moreover, give your newly planted evergreens a strong start with Dr. Earth Organic Starter Fertilizer which contains premium biologicals and organics for optimum plant starting success. Combine this with Fertilizer spikes in the spring, like Jobes or Ross Evergreen Tree Spikes to feed all season long.
TREATING PEST INFECTED SPRUCE TREES AND PINES
If there are significant signs of beetle or borer activity, then an application of a topical insecticide will need to be applied in combination with the above drench application. We recommend using Eight by Bonide and repeating this process 3 times at 2 week intervals.
Susceptible parts of trees should be coated with these insecticides so that the insect is poisoned while chewing holes to either enter or exit the tree.
Photo Citation:
Zimmerman Pine Moth – Whitney Cranshow, Colorado State University, Bugwood.org
Southern Pine Beetle, Pitch Tubes – Erich G. Vallery, USDA Forest Service SRS-4553, Bugwood.org