If you have Colorado Blue or Green Spruce trees on your property you might want to pay attention to area Spruce as you drive around. In recent years these trees have been under severe attack from a fungal condition called Rhizosphaera Needle Cast (aka Rhizo).

As you can see in the above photo the Spruce trees closest to the camera are dying from the bottom up. The damage is in the process of spreading all along this once beautiful line of trees and will kill them all in a few short years. Rhizo is a treatable disease, but treatment should commence as soon as possible to limit the damage.

Rhizo travels tree to tree as a microscopic airborne spores blowing in the wind for miles from infected Spruce. Birds and squirrels can also transfer this disease.

Rhizo damage usually displays on the lower half of the tree initially. Spruce owners will notice browning or even purple needles followed by dying limbs. Once these spores land on a healthy tree they are impossible to see with the naked eye. The infection won’t be noticeable until the damaged needles start to show up usually 12 to 15 months after initial infection. As a rule, with the fungus being so widespread in our area, without proper treatment these trees will continually decline year to year until death occurs.

Clients will ask…’If I treat my tree and my neighbor does not, can you still help my tree?’

The answer is yes, and this applies to all treatments that we provide. We always use the highest quality products and apply applications with proper timing which is just as important. With this game plan we can protect trees from fungal and insect issues during their infection cycles. Rhizo spores can land on your tree all day long to no avail. They will die on contact before they spread from within if proper treatment is supplied.

Clients also ask…’why does Rhizo start in the lower portions of the tree?’

This fungus, like all tree fungus issues, flourish in cool, shaded, damp environments. The lower quadrants of a Spruce catch more dripping rain from branches above and these lower limbs are shaded by their own upper canopy. Lower limbs are longer and more dense with one limb shading the one below it, causing more moisture to be trapped because it’s more difficult for the sun to penetrate the bottom of the tree and dry it out as quickly as it does in the upper portion.

Also worth noting…Spruce love as much sun as possible. Those dealing with shade from surrounding trees adds to its susceptibly to Rhizosphaera.

BELOW:
Another group of 3 Spruce after three (3) years of our fungicide spray applications coupled with high pressure root fertilization.