I received a note this past week from Marty Murie, owner of Nativescapes and certified arborist that I wanted to share….
Alert: Insect Damaging Spruce Trees on the Rise in Big Bear
I have been seeing a lot of Colorado Spruce trees infected with Green Spruce Aphids (Elatobium abietnum) this Spring. The population explosion can be attributed to the mild winters we’ve had the last few years. Spruce trees are one of the most prized ornamental trees planted in Big Bear appreciated for their shape, density, color and ability to adapt to our climate.
Symptoms: The aphid typically attacks interior needles which turn yellow. You may notice a shiny wet look on the needles referred to as “honeydew”. Most damage occurs on the lower portion of the tree but severe infestations can work their way to the top of the tree. The affected needles detach and drop early so you may notice an unusual amount of dead needles under your tree.
Life Cycle: The aphids actively feed in the Spring and Fall. Quite often the damage is done by early Summer and the adult population declines before a homeowner notices there is a problem. Trees that have been infected in the past will likely get infected again during the next cycle unless treated. Severe infestations can defoliate the tree leaving only the new years growth on the tips of the branches. It can take up to 5 years of growth for a tree to recover to its full density and appearance.
Control: Spraying the tree with an appropriate insecticide will get rid of the current population. Trees should be checked during the next cycle to insure they are free of aphids. Remember your plant biology; photosynthesis takes place in the needles which provides energy to support all functions of your tree. Less needles means less energy available. To off set the reduction of functioning needles we are recommending soil injections with a mixture of a mild fertilizer, micronutrients and microbial cultures to provide all elements necessary to promote a healthy recovery.
If you notice any of these symptoms on your Spruce trees I would recommend contacting Marty’s office immediately to discuss treatment options at 909-878-0050.