What Tree Diseases Pose A Threat To The Sitka Spruce?

The Sitka spruce is one of the tallest types of spruce trees, and its height and narrow width help showcase the tree's natural beauty. Sitkas feature blue-green needles, reddish cones, and thin textured bark that can lean either reddish brown or a purple-toned gray. Sitkas are a regal tree for any property in the tree's growing zones.

Keeping the Sitka tree on your property healthy can involve some maintenance and watching for signs of tree disease. Here are a few of the diseases that can affect the Sitka spruce and how a tree service can help protect your tree from serious damage.

Red Ring Rot

Red ring rot is caused by fungus that creates bark knots that feature red rings on the surface. The fungus within the knot continues to eat away or decay the wood inside. Eventually, the knot will collapse and form a white-tinged pocket with decayed wood on the inside. If the red ring rot takes hold throughout the trunk, the tree might die and need to be cut down by a tree removal company.

The red ring rot thrives in areas where the bark was already damaged. If you are starting to see knots appear, call in a tree trimming service to carefully prune away the affected area and prevent the disease from spreading further. Trimming, proper maintenance, and patience are the best treatments against red ring rot.

Rhizosphaera Needle Cast

This fungal needle cast disease causes the Sitka spruce's needles to turn yellow by summer and darken and drop from the tree by fall. The needles will often look healthy early in the growth season but progressively look unhealthier with the discoloration starting at the bottom of the tree and working its way up. Several years of severe infections can lead to the affected branches dying off though it is rare for the entire tree to die.

Prevention is the best fight against rhizosphaera needle cast since the fungus mainly attacks trees that are dehydrated or damaged. If your tree is already affected, you can call in a tree services company to apply a fungicide to prevent the disease from worsening or returning the following year.

Spruce Needle Rust

Spruce needle rust is another type of fungal disease that affects the needles of the Sitka spruce. The initial symptom of yellowing needles in summer can resemble needle cast. But the needle rust then progresses to form orange-colored growths on the needles that will later burst and release spores. Eventually, the affected areas of the tree will take on an overall orange-pink look before the needles fall off in the autumn.

The good news is that spruce needle rust is just a cosmetic issue and the problem will usually clear itself up. You might want to call in a tree service like Tri-Point Tree & Landscaping to remove the orange growths to prevent the spores from releasing, but you can otherwise wait out the problem.