Edible Forest Gardening

Brief Description

In 2005, Dave Jacke, with Eric Toensmeier (and, as Dave admits, the helping hand of numerous people 'behind the scenes'), provided a new framework from which to consider forest gardening. Their two volume seminal work, Edible Forest Gardens - Ecological Design and Practice for Temperate Climate Permaculture, has both offered a body of in-depth analysis for temperate climate forest gardening while setting the stage for future studies and advancements in this largely unexplored field.

Briefly, forest gardening is an ecologically-based design practice intended to mimic the patterns of forest systems by incorporating perennial-based, annual-mixed, sequences of plant communities. In this manner, one must imagine the full breadth of a forest - from the canopy level, to the understory of ephemerals and medicinals, to the interactions at the micro-organismic level of the soils. However, there is a clear distinction between gardening like the forest as opposed to gardening as the forest. Because one is designing for human-accessible and abundant yields, one is mimicking forest patterns for human good (though, as one finds, this often has indirect beneficial impacts beyond the human level - i.e., animal and insect habitat, revitalized soil beds, water capture etc.).

Forest gardening is modeled after what ecologists have learned from succesional studies:

"Succession studies show that patches are fundamental organizational units in natural ecosystems...to create structural diversity, we should respond to and mimic this patchy reality"

                                        ~Edible Forest Gardens - Volume 2 (p. 10)

With this in mind, the forest gardener is urged to imagine an ever-changing forest garden. This often entails a 'whole-istic' design process projecting successional stages of a forest garden. Consequently, one can begin their design process by modeling an 'end' stage of succession; tracking backward through a mid-successional stage; and installing (or planting out) their first trees, shrubs, and plants mimicking the pioneer stage of early succession.

Concepts

(in no particular order - these concepts are adapted from Dave Jacke's Edible Forest Gardens - Volume 2 and my own experiences.)

site preparation : Particularly in areas with 'poor' or compacted soil - often the results of previous agricultural monocropping. This will include anything you aim to accomplish prior to planting out your forest garden BUT should also be considered seriously if the healthy establishement of a young forest garden is in question. This practice can greatly improve the health of your forest garden as well as its inherent yield capacities. It will also minimize future work - if you simply plant your forest garden without attention to its soil quality you are creating unnecessary competition...both for scarce nutrients and with a pre-existing 'weed' seed bank.

Most poor soils can be improved by adding organic materials and/or breaking up hard-panned and compacted soils with deep-reaching perennial root systems. However, it is also beneficial to work with beneficial annuals. For example, Yellow Sweet Clover (Melilotus officinalis) is an introduced annual or biennial whose root system extends as far down as 20 feet . In this manner, the plant can serve as both a soil stabilizer and a dynamic accumulator during the early years of a young forest garden. This plant is often used in organic agriculture rotations as a cover crop. It can also be used in combination with a fast-growing grain crop for livestock feed over winter months. This past season, at Mark Shepard's New Forest Farm we covered an acre with millet and yellow sweet clover. The results: the livestock (3 holstein bull calves) received a healthy 3-5 round bales of millet/clover and the yellow sweet clover will grow back in spring adding continued soil stability during southwest Wisconsin's rainiest months. Ideally, one could feed 3-5 heads of livestock by performing this strategy on 2 to 3 acres. Back to the forest garden...

It should be noted that to correctly determine a given site's desired dynamic accumulators a series of soil tests and subsoil tests should be considered. Regardless, one ought to consider growing swaths of 'mulch plants'. i.e.,stinging nettle, comfrey, sorrels and docks, vetches etc that will uptake trace elements. These patches can be harvested and mulched or composted - either in a compost pile or in a fermented compost tea.

An interesting idea I have considered lately is the dual combination of composted 'weeds' in tea form (i.e. nettle, comfrey et al) with coppice-able dynamic accumulator trees (basswoods, birches, hickories, black walnut et al). In this manner one could create a fermented and slightly aged mulch material - a layer of organic materials providing many functions in a forest garden.

For detailed analysis on species lists applicable to this concept see Appendices 2 and 3 in Dave Jacke's Edible Forest Gardens - Volume 2, Design and Practice pp. 524-536

Resources

Dynamic Accumulators :

Martin Crawford's 1995 series "Fertility in Agroforestry & Forest Gardens" in Agroforestry News.

Robert Kourik - Designing and Maintaining Your Edible Landscape Naturally. 1986.

Lawrence Hill - Comfrey: Past, Present, Future. 1976.