Spruce Insects & Diseases

I N S E C T S

Damage to spruce from Cooley's Spruce Gall Adelgid Cooley Spruce Gall Adelgid
Brown, cone-like growth on the tips of the branches are a symptom of an infestation of Cooley Spruce Gall Adelgid.
Eastern Spruce Gall AdelgidEaster Spruce Gall Adelgid
The pineapple-shaped galls greatly stunt the growth of new spruce shoots. Trees demonstrate a wide range of susceptibility, some have many galls which kill the branch and others having few galls which allow for continued branch growth.
Spruce Spider Mite damage to spruce. Spruce Spider Mite
Browning of needles on the interior of a tree in summer can be a symptom of spruce spider mites. The insects are very small and so a magnifying glass or microscope will be needed to see the mites. 
Douglas-fir tussock moth
This is an important defoliator of spruce, Douglas-fir, true fir and other conifers.  Feeding by the larvae can cause complete defoliation of heavily infested trees.
Cytospora damage to spruce. Cytospora Canker
This condition begins by killing branches near the bottom of the tree and gradually works its way up the crown. Infected trees may live for many years but become increasingly unsightly. 
Spruce BudwormSpruce Budworm
The spruce budworm may be difficult to see. It feeds on the new growth causing it to curl. Close examination of curled new growth will be necessary to find the worm. 
Spruce needle miner damage to spruce.Spruce Needle Miner
Dead needles, webbed to the branches may be a symptom of the spruce needle miner. Close examination of the needles will reveal that the center have been mined.
D I S E A S E S

Rhizosphaera Needlecast damage to spruceRhizosphaera needlecast
This condition does not usually kill a tree; however, premature needlecast results in trees that are not marketable, or which are not acceptable in the landscape. 
O T H E R   P R O B L E M S

Salt damage to spruce. Salt Injury or injury from other chemicals usually results in dead branches starting at the bottom of the tree. The next higher dead branch will usually be offset so that the dead branches form a spiral pattern up the tree. The injury shown was caused by salt, for instance from septic systems, however other chemicals will cause the same general symptom. 
Early frost damage to spruce. Late spring frosts can kill tender new growth on spruce and other evergreens. Frost Injury is often not noticed until the injured growth turns brown.