What is wrong with my fruit trees?
On a recent walk around the fruit at Saughton I noticed that two of the plants had things wrong with their leaves. Some of the currants had raised red distorted patches and a couple of pear trees (interestingly just the Doyenne du Comice variety) had leaves with yellow blotches. I had no idea what was wrong or whether either were contagious, life threatening (to the tree!) or simply cosmetic. Photos were dispatched for advice to George Anderson, the Caley fruit guru, and also Chris Macefield of The Orchard Project, the charity that had supplied the fruit for the park. Unsurprisingly they came up trumps and my worries about these common issues were allayed.
The pest on the redcurrant is Currant Blister Aphid ( Cryptomyzus ribis). It can affect red, white and black currants and while it looks unsightly it does not generally affect the plant’s vigour or ability to bear fruit. The aphids feed on the young leaves and cause irritation. The leaves react to the aphid feeding sites and create the red raised areas. If you look underneath the leaf the aphids may well be seen. Best thing to do is to nip off the affected leaves and shoot tips and put them in the council bin. Alternatively just tolerate, squish the aphids or encourage aphid predators. The aphids are active in their wingless form from bud burst to July after which they fly off for their summer only to rerun to overwinter on the currants.
The yellow leaf patches on the pear are symptoms of an attack by the Pear Blister Mite (Eriophyes pyri). This is a common pest of pears and whilst it is unsightly it does not generally impact on the tree’s health or the quality of the fruit. If the tree is lightly affected the leaves and shoots can be removed but if heavily infested then removal of the leaves will be more damaging to the tree. The removed plant material should be disposed of in the brown bucket rather than in your household compost.
(Sarah Bennett is a Caley member, a member of the Caley Council and leader of The Friends of Saughton Park Community Orchard as well as being a regular volunteer for both the Friends and for The Caley. Watch out for further updates!)