Shoot Blight Of Cedar – Sirococcus strobilinus

Current Situation

  • A number of locations throughout the UK has seen infections in Atlantic Cedar caused by Sirococcus strobilinus


Closely Related Fungal Pathogens

  • conigenus sensu stricto
  • tsugae hitherto
  • piceicola

Susceptible Species

  • Cedrus Atlantica (Atlas cedar)
  • deodara
  • Hemlocks (Tsuga heterophylla and T. mertensiana) – Eastern hemlock (T. canadensis)

How It Spreads – A sexual spores are distributed by:

  • Rain splash
  • Strong winds
  • Seeds
  • Planting stock
  • Cut foliage

Symptoms – In the spring trees display:

  • Dead needles on the shoots, dead shoots.
  • The dead needles have a characteristic ‘pink’ colour
  • Needles and shoots become brown as the season progresses
  • The fungus can be seen on dead needles
  • Canker in branches
  • Change of colour in branches from green to dark red/purple
  • In some cases resin bleeding can be observed
  • During the winter months and into the spring the fungus can be seen on the surface of cankers
  • The phloem tissue can have brown lesions.


  • Could be a threat to ornamental trees in parks and large gardens


  • Currently no available treatment

Current Status

  • Listed in the European Union’s Plant Health Directive