Identification

• Pine needle scales are often found on spruce, pines and fir trees. These pests are 1/8 inches in length and are white in color. Attaching themselves to spruce tree needles, scale insects multiply rapidly by laying large numbers of eggs on host tree needles. After hatching, scale insects are known as crawlers that are active for about three weeks before attaching themselves to the tree to feed. After settling upon a feeding spot, scales molt and within a few weeks their white waxy coating of armor covers their body.
  
  

Effects

• Spruce trees infested with pine needle scales often look as if they have white tufts of cotton all over their branches and needles. Needles that are infested with large numbers of scales, often drop from the tree prematurely. Spruce trees often lose large numbers of needles and twig dieback can occur with prolonged infestation.
  
  

Natural Control

• Natural predatory insects can help control pine needle scale on spruce trees. According to Colorado State University's website, several species of parasitic wasps and lady beetles feed on pine needle scales reducing their numbers. However, natural predatory insects are not always enough to keep pine needle scale infestations under control in spruce trees.
  
  

Chemical Control

• Horticultural oils are usually effective in controlling pine needle scales. Apply horticultural oils during the dormant season and use an oil product with a 2 percent concentration. Spruce trees may become discolored temporarily after applying horticultural oil products. You may wish to apply oils to a small portion of your spruce before applying it to the entire tree. If no serious damage is evident after seven days, it is safe to apply the oils to the entire tree. Insecticides are available for control of scales in the crawler stage. These products often contain active ingredients such as permethrin or cyfluthrin and are most effective when applied after egg hatching while crawlers are small.