Hi, my son has a very old apricot tree in his garden (in Christchurch) but there are borer holes in the cut end of a branch that had been removed some time ago. Can borer be treated in a living tree, and if so, what would be your recommended treatment?

Hi Murray, yes, borer can be treated in a living tree. When making cuts to fruit trees it is always good practice to seal wounds with a water based paint or a specialty pruning paste to prevent borer entering the tree. There are several things you can do, if not the main trunk that is infected, cut the limb further back to 'clean' wood, where you don't see any borer damage, and seal the wound. Burn the infected material that comes off the tree so the larvae do not overwinter in the leaf litter or wood, don't store on the wood pile for winter. Get a fine piece of wire and poke it down the borer hole, if the larvae are there, hopefully you will pierce them and they do not survive. There are aerosol borer control products that can be used (same as household borer products) and injected into the tree, seal the hole with vaseline after applying. Lianne.