Michael and Jenny’s orchard of 2500 trees was planted in 2009 and has also been managed as single stems, although branching starts lower than Mike Davenport’s trees.
We looked at a tree that was badly damaged last year by a contractor’s equipment. A sucker has emerged which Michael is trying to train on as a replacement tree, but it’s quite spindly so far. This is partly because the lower buds have been removed early to try and focus the growth higher, but the plant hasn’t consolidated the growth in its trunk. This growth will only happen by encouraging branches to grow directly out from lower down, and this can be forced by notching the bark just above a dormant bud node. Cut a sliver of bark out from just above the bud, and hopefully the tree will respond by activating the bud’s growth. This growth can be removed later, once the trunk is better established.
Notched bark above a dormant node, to stimulate replacement growth (20 November)
Dormant bud starting to grow, and a new bud emerging below (10 December)
Two years ago the Pethericks hosted a TreeCrops demonstration day where edible apples (and other pipfruit) were grafted onto ornamental crabapples in the orchard. The grafts have been successful overall, which led to a discussion on the feasibility of grafting replacement hazelnut varieties onto existing orchard stock. Aside from the obvious hurdle that there isn’t currently a compelling replacement for Whiteheart (high quality, high yield, low suckers, good compatibility, precocious, good disease resistance…), grafting requires daytime temperatures consistently above 20 °C for several weeks. In Canterbury, the strong nor’westers are also a problem because of physical damage and the extreme drying effect. In principle, if these barriers could be overcome then grafting could be done on either suckers (by cutting back the original tree to spur new sucker growth) or by pruning the canopy and grafting onto the regrowth. Scion wood would need to be collected the previous winter then stored in a refrigerator until temperatures rose and all risk of frost had passed.