Shot Hole

Shot Hole is caused by the fungus Wilsonomyces carpophilus and is a common disease of stone-fruit, especially almond, plum, and apricot.

The fungus infects leaves, fruit and young shoots but is most noticeable on the leaves where it starts as very small (3-6mm) reddish spots with a yellow or light green halo. As the infection progresses the spots grow larger, the centres dry and eventually fall out leaving the telltale ‘shot-hole’ effect. Infected fruit has raised, brown scabby lesions. Infected fruit and shoots may exude gum.

In severe cases, the disease can affect plant vigour and fruit yield. The spores of this fungus overwinter in stem lesions and infected buds. The spores spread through water splash and as such the disease is more severe after wet winters or where the trees receive overhead irrigation. Certain copper-based sprays can be applied after leaf fall in autumn and again at bud swell in late winter to help control the disease. Talk to your local garden centre for more details.

 

Typical Shot Hole symptoms on leaves.

Shot Hole symptoms on almond leaf and fruit.