Tulip Tree
Symptom Cause  
Leaves or needles wrinkled or curled; discolored, stunted, tend to fall off
Aphids
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Rotting visible on branches; bark
Canker (fungus)
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Young portions of foliage disappear, young tips disappear; bark shredded on trunk
Deer
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Purplish spots on leaves
Gall Fly
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Leaves yellow and drop in summer
Not Enough Water
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Whitish-Gray coating on foliage
Powdery Mildew
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Leaves and branched encrusted with small bumps; stunted plant growth
Scale
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Leaves turn yellow at margins, dry; new leaves stunted; tree dies slowly, branch by branch.
Verticillium Wilt
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