Pine needle scale (Chionaspis pinifoliae)
GDD Window (base 50): 298-448 (1st generation), 1290-1917 (2nd generation)
Overview:
- Overwinter as live females or bright red eggs beneath the wax cover of the dead female
- Adult female is white, and oyster shaped, 1/8″ long, and found only on needles
- Adult males are small, winged insects that resemble tiny parasitic wasps and die after mating with females
- Crawlers are reddish, but turn yellowish tan, lose their legs, and never move again after settling
- Settled crawlers secrete a waxy covering over their bodies
- Needles turn yellowish, then brown with eventual dieback
- Foliage can look white to gray from a distance
- Reduction in plant health, sparse foliage, and death of infested twigs
- Host plants: Pines (Scotch, mugo, Austrian, red, white), Norway spruce, Colorado spruce
Management:
Cultural Practices:
- Natural predators: brown lacewings, green lacewings, lady beetles, parasitic wasps
- Keep growing areas and equipment clean
- Prevent dusty conditions
- Reduce plant stress
- Dispose of heavily infested plants
Materials:
- Contact insecticides:
- Carbamates [1A]: carbaryl
- Pyrethroids [3A]: –thrins
- Organophosphates [1B]: acephate (translaminar), malathion
- Systemic insecticides:
- Neonicotinoids [4A]: dinotefuran, acetamiprid, thiamethoxam
- Considerations:
- Will harm non-target species
- Timing is essential in controlling armored scales (target crawler stage before waxy covering forms)
Biorationals:
- Insecticidal soaps and horticultural oils
- Neem oil
- Insect growth regulators:
- Pyriproxyfen [7A]
- Buprofezin [16]
Disclaimer – Materials do not cover all possible control scenarios and are intended for licensed professionals. Tradenames do not imply endorsement and are used as examples. You must strictly follow the label for each compound prior to use. Rutgers is not responsible form is used materials or damages thereof. The label is the law. Labels will provide detailed information on use and restrictions. Additionally, application intervals, compatibility, surfactant use, PHI, PPE, important and other key information is described in detail. Always discuss treatments with your local agents. Note: Neonicotinoids can only be legally applied in commercial agriculture settings by licensed applicators. Guidelines and recommendations made in this presentation are specific to the state of New Jersey.