Then next big thing we've got to decide are what trees and large shrubs do we want in the canopy layer?

Essentially this come down making a large scale map (100:1 or 200:1) and some scale circles representing tree/ shrub canopy sizes when mature, then working out which mix of the following do we want, and can fit, in the space (leaving enough space for everything else between):

* Common fruiting trees
(Quince, Fig, Apple, Medlar, Apricot, Sweet/ Sour Cherry, Plums/ Gages/ Bullaces/ Damsons, Peach/ Nectarine, Japanese Plums, Pears)
* Less-common fruiting trees
(Juneberries/ Serviceberries, Stawberry Tree, Pawpaw, Dogwoods, Hawthorns, Blue Bean, Persimmons, Elaeagnus x ebbingei, Autumn Olive, Snowbell/ Silverbell Tree, Sea Buckthorns, Mulberries, Cherry Plum & Mirabelle, Blackthorn/ Sloe, European Elder, Rowans/ Whitebeams & Service Trees)
* Trees for nuts and seeds
("if you don't want to control squirrel numbers, then don't waste space in your forest garden by planting nut trees (with the exception of Sweet Chestnut)" Monkey Puzzle, Siberian Pea, Hickories/ Pecan, Chestnuts, Hazels, Maidenhair Tree, Heartnut, Black Walnut, Walnut, Pines, Almond, Oaks)
* Tree with edible leaves
(Limes/ Lindens, Chinese Cedar)
* Trees for herbs and spices
(Bay, Pepper Trees)
* Trees with other edible parts
(Maples, Birches, Sumachs)
* Firewood from coppice
(Common alder, Sweet Chestnut, Hazel, Eucalyptus, Ash, Black locust, Limes)
* Medicinal Trees
(Eucalyptus)
* Nitrogen-fixing trees
(Wattles, Alders, Siberian Pea, Redbuds & Judas Tree, Elaeagnus, Sea Buckthorns, Amur Maackia, Bayberries/ Wax Myrtles, Black locust/ False Acacia, Buffalo Berry).

Once we know the size of the site we can work out roughly how many trees we'll be able to fit, then we'll have to decide which ones we actually want to plant! (based on our requirements) :)

I really like the idea of trying to incorporate camping facilities within the garden. This could mean, for example, we'll need less nitrogen-fixers (because we'll have plenty of wee). And maybe we'd like to include trees to grow new poles for replacement yurts/ shelters in the future? And some firewood too to heat the shelter and cook food? (although I guess some of these outputs may be better suited to the existing little woodland).

Exciting!