Editorial - January 2010
A new forest garden model for temperate climates?
This month the guest writers’ section carries a question and answer session with Mark Briggs (Permaculture in Context), a student from St Andrew’s University, who came up with some very pertinent questions as part of the research foe his dissertation. Soon after our contact I had yet another request for input from another graduate student who wanted some ideas for lines of enquiry.
This is very promising. It means that Permaculture is spreading and being taken seriously by the scientific and
academic establishment. The more we can do to connect with people doing research the better, so I passed the second enquiry on to someone who will be familiar to many of you – Chris Dixon, from whom I learned so much on my own Permaculture Design Course.
Chris has been been managing his land near Dolgellau for a long time now, watching it develop naturally, with minimal interference, out of a previously sheep-scoured green desert, and many of his suggestions for research spring from his own experience there.
Here are the ideas he came up with:
“*Potential for gorse as an animal fodder.
*Changes in species' ranges due to climate change (temparature, rainfall etc.). ie. what medium to longer term species should we be planting now for our tomorrows?
*roles of fungi, particularly mychoremediation.
*is scrub woodland the most productive ecosystem in a temperate climate? If so, and I think it probably is, then shouldn't we be designing scrub forest gardens?
If the student's understanding of Permaculture design is at an integral level, then the most challenging work is in the area of peoplecare, as in eliciting and adequately supporting radical lifestyle changes”.
These all sounded very interesting. Last year I came across Chris’s excellent information on gorse on his website – see weblink and previous postings on our forum for more on that – and, as a result, I planted 50 gorse bushes around our would-be forest garden area as windbreak and nitrogen fixer.
The other idea that caught my attention was that of exploring scrub woodland as a model for forest gardens in a temperate climate, so I asked Chris to elaborate. Here are his further comments:
“I've come across several references and informed opinions to mixed scrub as being the most productive ecosystem for temperate climates, in terms of the trapping and storage of solar energy - the complex topography of scrub with its chaotic mix of plant types (climax, "understorey", shrub, forbes, grasses etc.) provides a huge open interface with masses of edge and lots of niche space for diversity, including more insects and hence more birds.
As scrub develops from grassland the biodiversity climbs rapidly but if the scrub tips over into forest then the canopy closes, the light-loving ground species die off and diversity can go down. By maintaining scrub the opportunities for diversity remain high.
As with the forest model and forest gardening, we would, in theory, simply (!) have to substitute "natural" species for our chosen food plants. As scrub offers more variety of niche we would have a much greater choice of species - something that is
very important in temperate climates, especially Britain, where, for example, our number of native trees is small, compared with, say Canada. For example, with nitrogen fixers we could include plants like gorse, which are normally shaded out during the forest succession, as well as the ground loving species like clovers, trefoils etc.
It’s been my model for a while but I've yet to formalise it.
Feel free to pass it on. Seems like it’s worth pursuing”.
And so I am passing it on here, and hope that some of you will experiment with this idea and let us have your thoughts on it. Our own design is at such an early stage that is will be easy to incorporate this model, and I am going to plant the few left-over gorse bushes in among the forest garden plants, and not only around the edges. If you do this, remember to buy pot-grown seedlings as gorse hates having its roots disturbed by transplanting – a tip from Chris.
I also like the idea of including red clover and trefoils as ground cover in the spaces to provide more nitrogen, as we have no room for alders, and probably only one eleagnus on one edge.
At the moment we have honeyberries, tayberries, loganberries and lingonberries in place. Next will come blackcurrants, gooseberries and blueberries, and we have a selection of small fruit and nut trees, including a small sweet chestnut variety, apples, damson and filbert. Still to come are pear, plum and cherry trees – all on smallish rootstock. When these are established we can start to think about perennial vegetables and herbs in the spaces. Meantime all work is halted in the freezing conditions. Time to put feet up and drool over the Agroforestry catalogue http://www.agroforestry.co.uk/ and Martin Crawford’s Forest Garden DVD. And of course, to wish you all a very happy and abundant New Year.