Golden Field Office – Insects & Diseases
Insects and diseases pose two of the most serious threats to a tree’s health.
As soon as you notice any abnormality in your tree’s appearance, you must begin a careful analysis to gain an understanding of the problem.
By examining the specific symptoms of damage and understanding their causes, you can make a reasonable diagnosis of the problem and select the proper treatment.
Learn More About Common Forest Insects & Diseases in the Golden Area
Insects
Douglas-fir Tussock Moth
- A moth with larva which attack and defoliate Douglas-fir as well as spruce and true fir species
- Defoliates starting from the top of the tree and working downward
- Control: Biological or chemical products are effective in springtime while new growth is appearing
Emerald Ash Borer
- A beetle which attacks and kills all true native North American ash trees, including green, white, black and blue ash, and their cultivars
- Lays eggs on the bark of an ash tree which subsequently hatch and burrow into the wood eventually girdling and killing the tree
Ips Beetle
- A bark beetle that attacks pine and spruce. In Colorado piñon ips commonly attack piñon pines.
- There are 11 species of ips found in Colorado.
- Control: Maintain vigorous tree health, insecticides can be used.
Mountain Pine Beetle
- Bark beetle that attacks pines including: lodgepole, ponderosa and bristlecone.
- Attracted to stressed trees and prefer large old trees
- Control: Maintain healthy stands or use Verbonone, an anti-aggregation pheromone that “repels” the beetles, chemical treatment
Diseases
Dwarf Mistletoe
- Affects all ages & sizes of ponderosa and lodgepole pines, as well as Douglas fir and piñon pine to a lesser degree.
- Parasitic plant that robs tree of nutrients & water, which causes growth reduction, poor tree form, loss of wood quality and subsequently premature death
- Control: Prune mistletoe infected branches and/or remove infected trees
