#rust  a reddish-brown discoloration of leaves and stems caused by a rust fungus
  supertype:  plant_disease__plantdisease  a disease that affects plants
  subtype:  white_pine_blister_rust__whitepineblisterrust__blister_rust__blisterrust__white-pine_rust__whitepinerust  any of several diseases of pines caused by rust fungi of the genus Cronartium and marked by destructive invasion of bark and sapwood and producing blisters externally

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