graft
wedge graft on Malus fusca
bridge graft on Malus fusca
crown graft on Malus fusca
Each spring, I take advantage of a narrow window of opportunity to perform some funky arboreal ‘hacking’ on fruit trees in my garden. Just before they come out of winter dormancy, it is possible to splice twigs from one tree onto the roots of another. Usually, both have to be from the same family, i.e. apples twigs should be grafted to apple trees, but there are some interesting exceptions. This year for example, I became intrigued by an Elizabethan recommendation that (sic):
The medlar is best be grafted on the hawthorn
(from Certain Experiments Concerning Fruit Trees by John Taverner, Gentleman
London, January 22,1600)
Now the medlar is an unusual, little fruit tree of ancient European lineage. It has fallen out of favour in recent centuries because (gulp) the fruit has to literally be eaten rotten, to be properly enjoyed. Why bother growing them, you might ask? Well, the beautiful white flowers are certainly a compensation. And there is something transgressive about growing a tree whose fruits in Shakespeare’s England were referred to as “open arse” and by the French at that time as “cul de chien” or dog’s asshole. (these facts courtesy of the wonderful blog, Giornalo Novo). Such frank pomological discussion certainly lends a new understanding to Mercutio’s remarks concerning Romeo, in Romeo and Juliet.
If love be blind, love cannot hit the mark.
Now will he sit under a medlar tree,
And wish his mistress were that kind of fruit
As maids call medlars, when they laugh alone.
In addition to scatological intrigue, the medlar tree posesses the unusual ability to occasionally form a graft hybrid or chimera when grafted to a hawthorn. This is true botanical weirdness in which the scar tissue that forms where the two plants join actually branches out and becomes a new kind of plant, an interspecies amalgam that is like a perfect morph of its two parents.
My grafting obsession started a few years ago, when I noticed some peculiar little apple-like trees growing in a thicket of salmonberries, in swampy area, quite unsuitable for growing conventional apples. A quick perusal of Pojar and Mackinnon’s Plants of Coastal British Columbia told me that these were Pacific crabapples or Malus fusca, a common, shrubby inhabitant of coastal wetlands. Unfortunately the crabapple’s fruits, while edible, were described as tiny and extremely tart, a poor substitute, I thought, for the Gravensteins, Yellow Transparents and Lord Lambournes I had been trying to establish in my garden. Many of the nursery grown apple trees I had been planting were disappointing in their slow growth, some even succumbing to diseases such as anthracnose canker. In marked contrast, the wild crab apples, seemed to thrive on neglect, successfully prevailing over the rampant salmonberries and bad drainage, with no human help. Would it be possible, I wondered, to somehow channel the vigour and disease resistance of these wildlings into the production of the succulent European apples I so wanted to eat? I decided that some experimentation was in order. . .
One day early in the spring, I grafted a few twigs from a Rhode Island Greening to one of the scraggly Malus fuscas, using simple wedge grafts and bandaged them up with strips of plastic cut from a grocery bag. In a few weeks, the buds on the Greening twigs started to swell as if they were still growing on their original tree and the joint where the twig had been grafted was starting to heal over. A short time later, a couple of lovely apple blossoms formed, along with some lush new leaves. I was elated! The experiment had worked.
The following spring, I got into a kind of crabapple grafting frenzy, grafting as many as five different apple varieties onto a single Malus fusca and trying out other techniques such as the crown graft and (the louchely named) whip and tongue graft. Perhaps my most ambitious effort was a bridge graft, which I used in resurrecting a crabapple tree someone else had tried hard to kill. The tree had been almost completely girdled, its trunk hacked into with an axe. It clung precariously to life with only a thin sliver of bark remaining to connect it to its roots. To remedy the situation, I performed a kind of bypass operation, grafting suckers that grew up from the base of the tree, around the wound and back into the trunk, to allow the sap to once again travel unimpeded. The result, while weird looking, was a completely reinvigorated crab, which quickly began to flourish, onto to which I grafted even more apples.
Most of my grafts “took” and, suckled by the sap stream of the fecund Malus fuscas, made astonishingly rapid growth. By the next year, most of the twigs had grown into substantial branches, poking up through the salmon berry thickets, and early that fall I was rewarded with a few plump Rhode Island Greenings from the graft I had made the previous year. Five years later, my little thicket of modified crabapples now yields bushels of juicy apples of several varieties, ripening from July right through to November with absolutely no effort from me -except for picking! While not completely eliminated, the effects of diseases such as canker seem to have been reduced -cankers appearing on the scion, now often spontaneously heal. Perhaps the native crabapple transfers some of its own immunity to apples grafted onto it.
As artificial as it sounds, grafting does occur naturally. Occasionally, trees will graft into each other at the places where neighbouring branches touch. This is often also seen in old hedges and ivy vines. Once connected, the branches start to exchange nutrients through their shared cambium, the inner bark containing the little tubes analogous to our own blood vessels. Other trees, like Douglas firs, patch into their neighbours’ roots, forming subterranean networks, sharing food, symbiotic fungi and even information, in the form of phytochemical secretions, turning the entire forest floor into an interconnected network of tree cognition. A few years ago, on a hike in Hawai’i Volcanoes National Park, I came across some ohi’a trees that were engaged in these enchanting, almost tantric grafts. It was as if I had stumbled onto some lignified, slow motion orgy, which had been ponderously playing itself out for centuries.
natural grafting
ohi’a trees, Volcano National Park
