Fir, Balsam
Symptom Cause  
Needles wrinkles/curl/discolor/fall off
Aphids
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When young portions of foliage disappear, or young tips disappear
Deer
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Needle tips yellowed
Needle Cast (fungus)
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Cream colored blisters on needles in spring; young trees stunted
Rust (on plants)
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Black powdery sooty mold fungus forms on honeydew; branches may die
Sooty Mold
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Needles and buds eaten out; defoliation
Spruce Budworm
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Needles stippled/yellow/dirty/silken webbing
Spruce Spider Mite
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