For the past dozen or so years, I have been performing various 'botanical re-mixing' experiments, investigating the capacity of native and naturalized
plants to serve as 'scaffolding' for related species that offer higher food yields.
pear on hawthorn hyperorganism
I have successfully grafted
numerous cultivars of domestic apple (Malus domestica)
to the Pacific crabapple (Malus fusca)
, a wild 'proto-apple' species native to the Northwest Coast of North America. Malus fusca
is a small tree that is very tolerant of poor conditions such as waterlogging and salt spray and shows considerable genetic variability. It often comes up in thickets of salmonberry (Rubus spectabilis)
, which is thorny and thus protects the young crabapple trees from deer browse. The crabapples, while edible, are relatively small and in contrast to many apples of cultivated origin, need to be dried or pickled to be enjoyed. So why not create a hyperorganism
to combine its hardy characteristics with the deliciousness of cultivated fruits?
Malus fusca fruit cluster
In fact, Malus fusca makes a compatible rootstock for many domesticated apples though it shows some variability from individual to individual in its willingness to play host to exotic twigs. The trees show resistance to many common apple diseases and their small size makes harvesting easy. I find the tendency to send up suckers useful, as it provides me a continuous supply of new places to graft. I have also 'top worked' several older trees, using a technique called 'crown grafting' (which is a little brutal), but more typically by wedge grafting twigs onto the ends of existing branches. These 'repurposed' trees now provide bushels of fruit on a site once unsuitable for a conventional orchard because of its seasonally waterlogged soil.
Medlar grafted to Mountain ash
Pear grafted to Hawthorn
Yet wilder and more contrasting hyperorganisms are possible! In addition to my previous example of the Bartlett Pear grafted to the hawthorn Crataegus monogyna,
I've succeeded in grafting pears to Mountain ash Sorbus aucuparia.
also seem compatible with both the Sorbus and the Crataegus and I have one Medlar that bears heavily on a hawthorn rootstock, (see slideshow at the bottom of this page.)
Grafting can also be used to repair damaged trees. Here are a couple of images showing the 'before' and 'after' instance of an apple tree that had been split, which I then repaired using a 'bridge graft' made up of the watersprouts coming up from around the trees base. I grafted these around the split to convey sap to the crown of the tree and in a few years these watersprouts thickened and encircled the wound, effectively giving the tree a new lease on life....
Split Malus fusca trunk bridge grafted for support
Same bridge graft a few years later
The medlar (Mespilus germanica) is now very well established on the hawthorn (Crateagus monogyna).
Both exist independently but together they form a kind of 'hyperorganism.'