Symptoms
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Elongated cankers on twigs and thin branches of several pine species, resin flow and dark discoloration of the cankered tissues. Occasionally also associated with slight shoot dieback. More rarely cankers on stems, mostly at their basis. In the cankers, blackish spore cushions are produced, from which asexual spores known as Digitosporium piniphilum are dispersed. These spores are branched and pale brown. Sexual fruiting structures are apothecia, disc-shaped, grey-black and about 1mm in size (hand lens). The cankers can be mistaken for hail wounds and other wounds, the dieback with Scleroderris-disease or Diplodia-dieback; stem cankers and resin flow may also be mistaken for the quarantine organism Gibberella circinata, cause of pitch-canker of pines.
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