Coral Spot fungus, Nectria cinnabarina

Every year the oldest Hazel twigs I use as pea sticks, to support Sweet Peas and Peas on my allotment, are covered with the pinhead-sized pink fungal blobs of the Coral Spot fungus, Nectria cinnabarina.

It’s a sign that the sticks have reached the end of their useful life. The fungus has grown inside the sticks and weakened them and what I’m seeing is the fungus’ fruit bodies breaking through the bark.

The pink blobs are the sexual stage of the fungus – later the blobs are replaced by the asexual sporing structures of the fungus, the conidia, which are reddish-brown.

Coral Spot is described as a weak pathogen of broad-leaved trees and bushes. On my Hazel twigs, it is a saphrophyte, feeding on the dead wood after it has been cut off the tree. But when deciduous trees have been pruned badly, leaving the ends of branches that won’t regrow, or when the bushes have been pruned in frosty or damp weather, Coral Spot may infect the wounded parts of the plant.

If this happens, the affected branches should be cut back in dry weather to healthy wood, preferably through the collar of the branch (the ring of slight swelling found at the base), where healing takes place most quickly. It also pays to clean your secateurs afterwards – I pour a small quantity of methylated spirits on the blades and burn it off. Infected branches should be removed and put in a Council compost bin (where the high heat in the large scale composting process should kill off the spores) or burnt.

But I’m happy to see the fungus live out its days on my Hazel sticks. It has never spread to my fruit bushes or trees and it provides a bit of subtle interest on the allotment in winter.