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Seiridium Canker

Seiridium canker Common name Seiridium canker Cypress canker Causal agent It is caused by three pathogens belonging to the genus Seiridium. The lower canopy starts showing signs of infection before the rest of the plant. Scientific name Seiridium cardinale Seiridium cupressi Seiridium unicorne Symptoms & Signs The first symptom of seiridium canker is the appearance of reddish-brown branches in the lower canopy, also called flagging. The branches and trunk also show small, reddish cankers near the base, oozing out the resin.  The bark also displays black, pustule-like pycnidia, which are the fruiting bodies and produce spores. Younger trees are at a greater risk of dying due to the infection. Transmission The infection spreads through spores that travel to healthy plants through wind, water, or infected tools. The spores enter the plant through an opening caused by injury or disease and attack the plant. Time of concern Spring to late summer Common hosts Cypress Junipers