[permaculture] Maximizing Omega-Level Diversity by Eric Toensmeier

Lawrence London lfljvenaura at gmail.com
Sat Aug 25 18:37:53 EDT 2012


Maximizing Omega-Level
Food Forests <http://permaculture.org.au/category/plants/food-forests/>, Food
Plants - Perennial<http://permaculture.org.au/category/plants/food-plants-perennial/>,
Plant Systems <http://permaculture.org.au/category/plants/plant-systems/>,
Trees <http://permaculture.org.au/category/plants/trees/> — by Eric
Toensmeier <http://permaculture.org.au/author/Eric%20Toensmeier> August 25,



*Note: this is a piece that was originally to be published in *Edible
Forest Gardens<http://permaculture.org.au/store/cartlist.html?keyword=edible%2Bforest%2Bgardens&btnSearch=Search>
*, which I coauthored with Dave Jacke. Yes, there are parts we cut out, it
would have been even longer! Dave reviewed and edited that version of this
article, though I have substantially updated it here and he is not to blame
for any errors that have crept in. This article only addresses the species
present in the Matrix of * Edible Forest Gardens* and, as such, only covers
the eastern forest region of the US and Canada from Zones 4-7. Using the
hotlinks in this and my last few posts you can construct a similar layout
for any climate.*

Compositional diversity, the mix of plant species and other living and
non-living elements, is a critical element of a stable forest garden
ecosystem. This is particularly important in the case of pests and
diseases, which frequently only attack closely related plant species. For
example, many of the fruits that grow in our climate are from the Rose
family, including apples, pears, cherries, peaches, and plums.  While these
are delicious fruits, they share many pests and diseases, like the dreaded
plum curculio. By diversifying the forest garden to include unrelated
fruits like kiwi, pawpaw, and persimmon, you can make sure that curculios
will not ruin all of your harvest in a bad year. Maximizing compositional
diversity can also help to create resource-partitioning guilds, because
plants from different families frequently have different strategies and use
different nutrients, have different root patterns, or may be otherwise less
likely to compete. For example, plants in the lily order tend to have bulbs
or tubers close to the soil surface, while many members of the Apiaceae (in
the aralia order) are typically taprooted or have deep, branching roots.

*Edible fruits of blue bean, Decaisnea fargesii. A member of the very minor
Lardizabalaceae family, in the buttercup order Ranunculales. This species
is barely related to common forest garden fruits like pears, blueberries,
grapes, sharing few or no pests and diseases with them, and thus an
example of omega level diversity in action. Plus it looks super cool!*

*What is omega level diversity?*

In biological language, *alpha *diversity indicates the total number of
species in an ecosystem. While useful, alpha diversity does not tell us
anything about the relationships between those species – for all we know,
those 100 species could all be oaks, or they could be completely unrelated.
*Omega *level diversity looks at an ecosystem’s diversity at higher levels,
measuring a deeper diversity. This ‘deep’ diversity is likely to be the
most important contributor of the benefits of compositional diversity.
Gardening for omega level diversity (‘kinship gardening’) was developed by
Alan Kapular and Olafur Brentmar, and carried forward by David
Theodoropoulos. In our selection of the species used in the Plant Species
Matrix, we worked hard to maximize diversity at the omega level. The
relevant distinctions of omega diversity used here are:

   - *Division.* This is the highest level of omega diversity to consider.
   There are ten great divisions of plants, representing different lineages
   that diverged many millions of years ago. Some are truly ancient and have
   dwindled to a small number of species – the most extreme example being the
   ginkgo, the last representative of its entire division. Of these most
   ancient groups of plants, which once fed the dinosaurs, the species matrix
   includes representatives of the bryophyte, conifer, horsetail, ground pine,
   gingko, and fern divisions (only three divisions are not represented, and
   these are both small in number of species, and primarily represent tropical
   species not suited to our climate). However, the vast majority of living
   species are in the recently evolved (geologically speaking) angiosperm
   division (the flowering plants) – as are the vast majority of species in
   the matrix (564 of the 593). Species from six of the ten divisions are
   featured in *Edible Forest Gardens.*
   - *Broad Angiosperm Groupings**. *These are large groups within the
   flowering plants that share a common ancestry. The matrix includes
   representatives of all of these clusters of flowering plants (there is not
   a direct parallel in the other divisions).
   - *Order. *Orders are groupings of families. The plants within an order
   may show similarities – as in the Fagales order which includes many
   families featuring wind-pollinated, nut-bearing trees and shrubs.  Both
   have hardy genera with edible, mucilaginous leaves. The Plant Species
   Matrix contains representatives of **35 of the 63 plant orders or
   free-standing families.
   - *Family. *A grouping of related genera. We find increasing similarity
   between species and genera at the family level. A well-known example is the
   heath family (Ericaceae), the majority of which are adapted to grow in
   highly acid environments due to a symbiosis with a group of mycorrhizial
   fungi. Nonetheless a family may have great variation, including everything
   from annuals to long-lived forest giants. The matrix includes
   representatives of 98 of the total of 764 plant families.
   - *Genus. *A grouping of similar species. For example, all the oaks are
   of the genus *Quercus. *The Plant Species Matrix contains 319 of the
   roughly 14,000 world genera.
   - *Species. *The species is the basic unit of plant classification.* *In
   theory members of a species are distinct from other species in the genus,
   and can pollinate each other and cannot pollinate other species. In
   practice, it can be quite a bit more fluid than that. However, anyone can
   tell a six-foot highbush blueberry bush  (*Vaccinnium corymbosum*) is
   different from a low-growing mat of lowbush blueberry (*V. angustifolium*).
   *Edible Forest Gardens *features 593 of approximately 300,000 known
   plant species.

*How to maximize omega diversity in your forest garden.*

You may find yourself torn in several directions while selecting species.
On the one hand, it is desirable to maximize compositional diversity at the
omega level. On the other hand, certain important uses and functions are
limited to certain families. Nitrogen fixation is mostly limited to the
legumes (Fabales) and certain orders within the rose (Rosales) and beech
(Fagales) orders . Specialist nectary plants are generally limited to the
Apiaceae, Araliaceae, Saxifragaceae, and portions of the Asteraceae. The
great majority of fruit and nut species that can grow in cold climates are
in the rose order (Rosales) – in fact, almost a quarter of all species in
the Plant Species Matrix are in that order! Thus there is little avoiding
the fact that your garden is likely to have heavy representation from these
groups of plants.

Beyond this limitation, however, you can make an effort to include as wide
a sampling of diversity as possible. Groundcovers, dynamic accumulators,
and shelter and nectary plants come from a great diversity of families, and
you will find a remarkable range of edibles to choose from as well. When
selecting species from the Plant Species Matrix, look up their families in
the table below. Keep track of the families, orders, and superorders you
are including. Wherever possible, make decisions that maximize diversity.
Try to avoid over-dependence on the Rose family in particular, perhaps by
substituting persimmons for apples, or one of the edible honeysuckle
species for juneberries. We have made an effort to provide you with a
diverse assemblage of species to choose from.

*Table One: Plant Families listed in Edible Forest Gardens and their
Higher-Level Relationships***

Families are listed alphabetically.  Columns to the right show the order,
group, and division to which each family belongs. The numbers in
parentheses indicate the number of order, families, genera and species from
that group that are represented in the Plant Species Matrix in *Edible
Forest Gardens*. For ease of use I have updated families, orders, and
groups here, but not the species and genera themselves.

*Table Two: Relative Representation of Divisions*

This is the highest level of diversity. Note we still have relatively few
of these except ferns and conifers. Note that the cycad division is
strictly tropical and thus cannot be represented in a cold climate forest
  Marchiantophyta (liverworts) 0  Anthoceratophyta (hornworts) 0  Bryophytes
(mosses) Mosses (1)  Lycopiodopsida (clubmosses) Clubmosses (1)  Pteridophytes
(ferns and horsetails) Ferns (14)  Horsetails (1)  Cycads 0  Gingkphytes
(Gingko) Gingkos (1)  Coniferophytes (Conifers) Conifers (10)  Gnetophytes
(jointfirs) 0  Angiospermatophytes Flowering plants (565)
*Table Two: Relative Representation of Flowering
Plant Groups and Orders*

**Note that some orders are strictly aquatic or tropical and thus cannot be
represented in a cold climate forest garden.
  Unclassed Angiosperms Amborellales (0)  Nymphaeales (0)  Austrobaileyales
(2)  Magnoliids Piperales (4)  Laurales (4)  Magnoliales (2)
Canellales (0)  Chloranthales
(0)  Monocots Alismatales (2)  Asparagales (30)  Dioscoreales (2)  Liliales
(10)  Commelinales (2)  Poales (13)  Zingiberales (0)  Arecales (0)
(0)  Pandanales (0)  Petrosaviales (0)  Acorales (0)  Eudicots Boraginaceae
(5)  Araliales (37)  Aquifoliales (1)  Asterales (48)  Brassicales
(11)  Buxales
(1)  Caryophyllales (23)  Cornales (6)  Dipsicales (10)  Ericales (29)  Fabales
(60)  Fagales (45)  Gentianales (6)  Geraniales (1)  Lamiales (29)
(5)  Malvales (8)  Myrtales (4)  Oxidales (4)  Ranunculales (9)  Rosales
(102)  Sapindales (10)  Saxifragales (21)  Solanales (3)  Vitales (4)
(0)  Sabiaceae (0)  Proteales (0)  Trochodendrales (0)  Gunnerales (0)
(0)  Celastrales (0)  Zygophyllales (0)  Huerteales (0)  Picraminiales
(0)  Crossosomotales
(0)  Dilleniaceae (0)  Berberidopsidales (0)  Santalales (0)
Garryales (0)  Escalloniales
(0)  Paracryphiales (0)  Bruniales (0)

In review, how did we do in selecting for omega diversity? Well pretty good
in fact. We could improve at the all-important division level. As I now
know both liverworts and hornworts fix nitrogen, I might encourage people
to add those divisions. Cycads won’t grow here, but one could add the
Gnetophyte *Ephedra*, which Dave and I actually considered but were turned
off by its toxicity — it is really more of a medicinal than a food. If you
were to do all this in your cold climate forest garden you could represent
9 of the 10 great living divisions of plants!

We did pretty well on the magnoliids and unclassed angiosperms as well, not
much I’d add there to be honest.

Monocots? You might add *Acorus calamus* in a wet sunny spot to gain the
Acorales, but much more exciting are the hardy edible gingers from
Zingiberales, especially *Zingiber mioga* and *Curcuma zedoaria.*

*Zedoary (Curcuma zedoaria), a hardy ginger relative used as a spice and a
rhizomatous starch source, would add the Zingiberales order to your
of diversity. Hardy to zone 6b and a shade-lover, this should be much more
widely grown in cold-climate forest gardens.*

As for the Eudicots, we have pretty good representation. From Cucurbitales
you could add *Cucurbita foetidissima*, the buffalo gourd, and perhaps the
weedy eastern native *Melothria pendula. *

*Review of Omega-Level Categories*

Interestingly, humans can eat very few of the non-flowering plants (mosses,
horsetails, ferns, conifers, etc.). It has been speculated that, while
mammals diversified at the same time as the flowering plants, we have never
learned to make good use of these ancient groups that came about in the age
of dinosaurs or before. In forest gardens, we can make use of many of these
plants as groundcovers, as well as consuming the nuts of ginkgos and
several conifer genera. The numbers in parentheses indicate how many
species from the genus are listed in Edible Forest Gardens.**


*This group of spore-bearing plants emerged 750-500 million years ago,
making them among the earliest land plants.*

Family: Polytrichiaceae

Genera: *Polytrichium* (1)

Ancient and primitive, but still quite successful, many moss groundcovers
are well adapted to the shady conditions of the forest garden.
Here’s Polytrichum commune, photo by
Sten<http://creativecommons.org/licenses/by-sa/3.0>via Wikimedia


Not as old as you might think, the spore-bearing lycopodiums began to
diversify as much as 200 million years ago.

Family: Lycopodiaceae

Genus: *Lycopodium* (1)

**A Lycopodium species in the understory of an old-growth hardwoods forest.
It can grow more densely, to make a tighter groundcover.*

Horsetail (Equisetum arvense), an ancient and extremely vigorous eastern
native groundcover. Thoroughly unrelated to all other forest garden
groundcovers except the distantly to the ferns, making it a good choice for
preventive pest and disease control. Has medicinal uses and serves as a base
for a fungicidal spray.*

*DIVISION: PTERIDOPHYTA (Ferns & Horsetails)*

A large group of spore-bearing plants once featuring dominant tree species,
now thriving in the understory of conifers and flowering plants. * *

*Order:* *Equisetales*

Family: Equisetaceae

Genera: *Equisetum* (2)

The single remaining genus of an ancient group of plants. Dynamic
accumulators, with some fine groundcovers.

*Fern Orders*

Ferns visually make a forest garden feel like a forest. They leaf out late
in the spring, and thus make fine companions to spring ephemeral plants. I
confess I’ve not yet found the perfect contemporary listing of fern
relationships. For now I’ll just list their families here.

Family: Adiantaceae

Genera: *Adiantum* (1)

Family: Polypodiaceae

Genera: *Polypodium* (2)

**Family: Blechnaceae

Genera:  *Woodwardia* (2)

Family: Dryopteridaceae

Genera:  *Athyrium* (1), *Dryopteris* (1), *Gymnocarpium* (1), *Matteuccia*(1),
*Onoclea* (1), *Polystichum* (1), *Thelypteris* (1)

Family: Thelypteridaceae

Genera:  *Thelypteris* (1)

Family: Dennestaedtiaceae

Genera:  *Dennstaedtia* (1)

Ostrich fern (Matteuccia struthiopteris), an eastern native fern with edible
shoots, also a fine groundcover for moist and/or shady areas.*


The sole remaining species in what was once a diverse and important
division of plants – imagine a day far in the future when only one species
of flowering plant remains to represent all the flowers of today’s world!
About 200 million years old.

*The edible nuts and horrible-smelling, rash-causing “fruit” of ginkgo.
Note that “stinkless” female varieties are available in the nursery trade.
Photo by jy mit Kamera via Wikimedia Commons.*

*Order: Ginkgoales*

Family: Ginkgoaceae

Genera:  *Ginkgo* (1)

Korean nut pine (Pinus koraensis), an edible nut pine showing
cones on 30-year old seedling trees.*


*Perhaps 350-300 million years old. Commonly associate with ectomycorrhizal

*Order: Araucariales*

Family: Araucariaceae

Genera:  *Araucaria* (1)

*Monkey puzzle, Araucaria araucana, has enormous cones with edible nuts.
Photo by scott.zona via Wikimedia Commons.*

*Order: Pinales*

Family: Pinaceae

Genera:  *Pinus* (8)

*Order: Taxales*

Family: Cephalotaxaceae

Genera:  *Cephalotaxus* (1)

*The conifers are an exception among the non-flowering plants in providing
a large number of edible species. As evergreens, they are also important
wildlife cover plants. *

*Japanese Plum Yew (Chephalotaxus harringtonia), a conifer in the order
A shrub with edible fruits and nuts, tolerating substantial shade.*


*Emerged perhaps 140 million years ago, thought to have co-evolved with the
great diversification of insects as pollinators and herbivores. *

*Unclassed Angiosperms*

*Order: Austrobaileyales*

Family: Schisandraceae

Genera:* Illicium* (1), *Schisandra* (1)

**Though its home in the angiosperms is not yet clear, Florida star anise
(Illicium floridanum) is a marvelous shade-loving eastern native spice
plant hardy through zone 7 and even a bit colder.*


This broad group came into being 200-130 million years ago. Scientists are
still clarifying the magnoliids relationship to the monocots and eudicots.
Most of the magnoliids were formerly classed with the eudicots in a large
group called the dicots, which is no longer a contemporary category.

**Pawpaw (Asimina triloba), best of the Magnoliids for the cold-climate
forest garden.*

*Order: Piperales*

Family: Aristolochiaceae

Genera: *Asarum* (3)

Family: Saururaceae

Genera: *Houttuynia* (1)

*Wild ginger (Asarum canadense), a native medicinal woodland
groundcover in the Piperales.*

*Order: Laurales*

Family: Calycanthaceae

Genera: *Calycanthus* (1)

Family: Lauraceae

Genera: *Lindera* (1), *Persea* (1), *Sassafrass* (1)

*Order: Magnoliales*

Family: Annonaceae

Genera: *Asimina* (1)

Family: Magnoliaceae

Genera: *Magnolia* (1)

*Despite being in different families, pawpaw, spicebush, sassafras, and
Carolina allspice all have strongly aromatic leaves that are toxic, and
each has their own butterfly species that can tolerate the toxins. *

Carolina allspice (Calycanthus floridus), a typical Laurales order shrub
with spicy aromatic parts and a special relationship with butterflies.*


A large cluster of plants, with the common trait of a single cotyledon leaf
emerging at germination. Tending to be herbaceous in cold climates, and
featuring many useful bulb, tuber, and leaf crops.

*Order: Alismatales*

Family: Araceae

Genera: *Amorphophallus* (1), *Colocasia* (1)

Edible leaves of taro (Colocasia esculenta), thought of as tropical but
hardy to
zone 7b. Needs multiple years to for tuber yield in short-season areas
but a fine leaf crop for wet sun to partial shade.*

*Welsh onion (Allium fistulosum), one of many excellent perennial
onions for the forest garden.*

*Order: Asparagales*

Family: Amaryllidaceae

Genera: *Allium* (8), *Triteleia* (1)

Family: Asparagaceae

Genera:  *Asparagus* (1), *Camassia* (3), *Clintonia* (1), *Maianthemum*(1),
*Medeola* (1), *Polygonatum* (1), *Smilacina* (1), *Streptopus* (2), *
Uvularia* (1), *Yucca* (1)

Family: Xanthorrhoeaceae

Genera: *Asphodeline* (1), *Hemerocallis* (3)

Family: Iridaceae

Genera: *Crocus* (1), *Iris* (1)

*Order: Dioscoreales*

Family: Dioscoreaceae

Genera: *Dioscorea* (2)

**Impressive tuber of Chinese yam (Dioscorea opposita).*

*Order: Liliales*

Family: Liliaceae

Genera: *Erythronium* (1), *Fritillaria* (1), *Lilium* (6)

Family: Smilacaceae

Genera: *Smilax* (1)

Family: Trilliaceae

Genera: *Trillium* (1)

**Kamchatka lily, Fritillaria camschatcensis, has edible bulbs.
Photo by S64 <http://www.gnu.org/copyleft/fdl.html> via Wikimedia Commons.*

*Order: Commelinales*

Family: Commelinaceae

Genera: *Commelina* (1), *Tradescantia* (1)

**Virginia dayflower, Commelina erecta, is representative of the
– looking like a grass with insect-pollinated flowers instead of
Photo by Assaf Shtilman <http://www.gnu.org/copyleft/fdl.html> via
Wikimedia Commons.*

*Order: Poales*

Family: Cyperaceae

Genera: *Carex* (1)

Family: Poaceae

Genera: *Andropogon* (1), *Arundinaria* (1), *Chasmanthium* (1), *
Phyllostachys* (3), *Sasa* (1), *Secale* (1),* Semiarundinaria* (1), *
Sorghum* (1), *Tripsacum* (1), *Triticum* (1)

Edible shoots of Phyllostachys bamboos. Many Poales associate with
fungi which live inside the leaves and help minimize herbivory. Almost half
of these species have the efficient C4 metabolism (warm-season grasses).*


Most of the group formerly known as dicots live here now. The eudicots have
two cotyledons at germination like the more primitive Magnoliids, but among
other differences they have distinctive three-parted pollen grains. This is
the largest group of flowering plants, which is itself the largest division
of plants.

*Unplaced Family:* Boraginaceae

Genera: *Borago* (1), *Mertensia* (1), *Symphytum* (3)

Though unplaced within the eudicots, comfrey is one of the most commonly
planted forest garden herbs. This is the hybrid “Hidcote blue,” a running
dwarf that is a great groundcover and, like other comfreys, is a dynamic
accumulator that provides great habitat for beneficial insects and

*Order: Araliales*

Family: Apiaceae

Genera: *Bunium* (1), *Conopodium* (1), *Cryptotaenia* (2), *Cymopteris*(2),
*Erigenia* (1), *Eryngium* (1), *Foeniculum* (1), *Heracleum* (1), *
Levisticum* (1), *Ligusticum* (3), *Lomatium* (4), *Myrrhis* (1), *Osmorhiza
* (2), *Perideridia* (1), *Pimpinella* (1), *Polytaenia* (1), *Sium* (1), *
Taenidia* (1), *Thaspium* (2),* Zizia* (2)

Family: Araliaceae

Genera: *Aralia* (5), *Panax* (2)

Sweet cicely (Myrrhis odorata) is a classic Apiaceae umbel flower,
attracting beneficial insects in mid-spring. All parts are
with the green seeds a special favorite.*

*Order: Aquifoliales*

Family: Aquifoliaceae

Genera: *Ilex* (1)

The native Ilex glabra has desirable charcteristics for attracting
birds: it is evergreen, thicket-forming, and has bird food berries.
Gardeners in zone 7 might add the caffeine-producing yaupon, Ilex vomitoria.

*Order: Asterales*

Family: Asteraceae

Genera: *Achillea* (2), *Antennaria* (2), *Arnoglossum* (1), *Artemisia*(3),
*Aster* (2), *Balsamorhiza* (1), *Bellis* (1), *Chamaemelum* (1), *
Chrysogonum* (1), *Cichorium* (1), *Conoclinium* (1), *Coreopsis* (3), *
Echinacea* (1), *Erigeron* (1), *Helianthus* (5), *Heliopsis* (1), *
Hieraceum* (1), *Lactuca* (1), *Parthenium*(1), *Petasites*(1),
*Senecio* (2), *Silphium* (3), *Smallanthus* (1), *Solidago* (3), *Taraxacum
* (1), *Vernonia* (1).

Family: Campanulaceae

Genera: *Campanula* (3), *Platycodon* (1)

Family: Lobeliaceae

Genera: *Lobelia* (1)

Scorzonera (Scorzonera hispana) in the Asteraceae. Though not of the
that attracts beneficial insects, worth growing for the edible roots,
and especially the cooked flowerstalks when the buds are still closed.*

*Order: Brassicales*

Family: Brassicaceae

Genera: *Arabis* (1), *Armoracia* (1), *Brassica* (1),* Bunias* (1),*Cardamine
* (3), *Crambe* (1), *Diplotaxis* (2), *Nasturtium* (1)

**The edible ‘broccolettas’ of Crambe cordifolia are similar
in flavor to annual brassicas.*

*Order: Buxales*

Family: Buxaceae

Genera: *Pachysandra* (1)

**Groundcover of native Pachysandra procumbens. Including native
Pachysandra is a great example of maximizing omega diversity
– this species is barely related to anything else in the forest garden,
letting us sample its entire order and perhaps minimizing pest and
disease pressure as well.*

*Order: Caryophyllales*

Family: Cactaceae

Genera: *Opuntia* (1)

Family: Caryophyllaceae

Genera: *Pseudostellaria* (1), *Stellaria* (2)

Family: Amaranthaceae

Genera: *Atriplex* (1), *Beta* (1), *Chenopodium* (1)

Family: Phytolaccaceae

Genera: *Phytolacca* (1)

Family: Polygonaceae

Genera: *Oxyria* (1), *Polygonum* (3), *Rheum* (3), *Rumex* (3)

Family: Portulacaceae

Genera: *Claytonia* (3), *Montia* (2)

* **
**The edible leaves of good King Henry (Chenopodium bonus-henricus)
are classic Caryophyllales.*

*Order: Cornales*

Family: Cornaceae

Genera: *Cornus* (6)

*The edible fruits of Cornus mas, Cornelian cherry dogwood.*

*Order: Dipsicales*

Family: Caprifoliaceae

Genera: *Linnaea* (1), *Lonicera* (4), *Viburnum* (3)

Family: Valerianaceae

Genera: *Centranthus* (1)

Family: Sambucaceae

Genera: *Sambucus* (1)

*Red valerian (Centranthus ruber), a favorite perennial vegetable
of Martin Crawford, from the Dipsicales.*

*Order: Ericales*

Family: Actinidiaceae

Genera: *Actinidia* (3)

Family: Diapensiaceae

Genera: *Galax* (1)

Family: Ebenaceae

Genera: *Diospyros* (2)

Family: Ericaceae

Genera: *Arbutus* (1), *Arctostaphylos* (1), *Epigaea* (1), *Gaultheria*(3),
*Gaylussacia* (2), *Rhododendron* (1), *Vaccinium* (7)

Family: Polemoniaceae

Genera: *Phlox* (4)

Family: Pyrolaceae

Genera: *Chimaphila* (2)

Family: Styracaceae

Genera: *Halesia* (1)

*Highbush blueberry (Vaccinium corymbosum) is a
delicious representative of the Ericales. *

*Order: Fabales*

Family: Fabaceae

Genera: *Acacia* (1), *Amorpha* (3), *Amphicarpaea* (1), *Apios* (3), *
Astragalus* (4), *Baptisia* (2), *Caragana* (3), *Cercis* (1), *Clitoria*(1),
*Colutea* (1), *Cytisus* (1), *Desmodium* (2), *Genista* (3), *Gleditsia*(1),
*Glycyrrhiza* (3), *Hedysarum* (1), *Indigofera* (1), *Lathyrus* (4), *
Lespedeza* (2), *Lupinus* (2), *Maakia* (1), *Medicago* (1), *Phaseolus*(1),
*Prosopis* (1), *Psoralea* (1), *Robinia* (3), *Sophora* (1), *Strophostyles
* (1), *Stylosanthe*s (1), *Thermopsis* (1), *Trifolium* (2), *Vicia* (3), *
Wisteria* (3)

**A string of edible tubers of timpsila or prairie turnip (Psorales
esculenta), a nitrogen
fixing Fabales species. The legumes are a large family, well represented in
the edible
forest garden as nitrogen-fixers. Legumes tend to be poisonous or spiny to
their nitrogen-rich foliage, but also include many of the most important
food plants in the world. *

*Order: Fagales*

Family: Betulaceae

Genera: *Alnus* (4), *Betula* (2)

Family: Corylaceae

Genera: *Corylus* (7)

Family: Fagaceae

Genera: *Castanea* (3), *Fagus* (2), *Quercus* (13)

Family: Juglandaceae

Genera: *Carya* (4), *Juglans* (5)

Family: Myricaceae

Genera: *Comptonia* (1), *Myrica* (3)

**Hybrid hazel (Corylus), classic Fagales. An important order for cold
food forests, featuring edible nuts and actinorhizal nitrogen fixers.*

*Order: Gentianales*

Family: Apocynaceae

Genera: *Asclepias* (2)

Family: Rubiaceae

Genera: *Houstonia* (1), *Mitchella* (1)

Family: Hydrophyllaceae

Genera: *Hydrophyllum* (1)

**Native edible-leaf Hydrophyllum loves shady forest gardens.

*Order: Geraniales*

Family: Geraniaceae

Genera: *Geranium* (1)

Wild geranium (Geranium maculatum) is a fine native groundcover from
the Geraniales. Here’s another example of a groundcover, as good as
any other, that can stand in as representative for an entire order.*

*Order: Lamiales*

Family: Lamiaceae

Genera: *Agastache* (1),* Blephilia* (2), *Calamintha* (1), *Clinopodium*(1),
*Cunila* (1), *Lycopus* (1), *Melissa* (1), *Mentha* (6), *Monarda* (2), *
Origanum* (1), *Pycnanthemum* (2), *Rosmarinus* (1), *Salvia* (1), *Satureja
* (1), *Stachys* (3), *Thymus* (1)

Family: Scrophulariaceae

Genera: *Veronica* (1)

Family: Verbenaceae

Genera: *Verbena* (1), *Vitex* (1)

*Bee balm (Monarda didyma) is typical of the Lamiales – aromatic and
somewhat weedy. An important group for forest gardens. In cold climates
the Lamiales tend to have similar niches as aromatic herbaceous generalist
nectary species. Also frequently adapted to the partial shade found
in forest gardens. Many are tea or culinary plants.*

*Order: Malphigiales*

Family: Passifloraceae

Genera: *Passiflora* (1)

Family: Violaceae

Genera: *Viola* (4)

The flowers and fruit of maypop (Passiflora incarnata) are like nothing
else in
the cold-climate forest garden. Another major tropical fruit order with few
cold-climate offerings, though both hardy passionfruit and violets are
great to have.*

*Order: Malvales*

Family: Malvaceae

Genera: *Alcea* (1), *Althaea *(1), *Callirhoe* (1), *Hibiscus* (1),
*Tilia* (2)

Purple poppy-mallow (Callirhoe involucrata) has the mucilaginous edible
typical of its family, plus edible roots. A nice groundcover too. Malvaceae
for cold climates tend to be mucilaginous edible leaf crops.*

*Order: Myrtales*

Family: Melastomataceae

Genera: *Rhexia* (1)

Family: Myrtaceae

Genera: *Eucalyptus* (1)

Family: Onagraceae

Genera: *Epilobium* (2)

Fireweed (Epilobium angustifolium), perhaps our best cold-climate edible
in the Myrtales. A minor group in cold climate forest gardens, though
many fantastic fruits like guava and related genera for warmer climates.*

*Order: Oxidales*

Family: Oxalidaceae

Genera: *Oxalis* (4)

Violet wood sorrel (Oxalis violacea), with edible leaves and bulbs
showing the characteristic sour flavor of this family.*

*Order: Ranunculales*

Family: Berberidaceae

Genera: *Berberis* (1), *Jeffersonia* (1), *Mahonia* (2), *Podophyllum* (1)

Family: Lardizabalaceae

Genera: *Decaisnea* (1)

Family: Ranunculaceae

Genera: *Aquilegia* (1), *Coptis* (1)

Family: Papaveraceae

Genera: *Dicentra* (1)

Creeping Oregon grape (Mahonia repens), an evergreen groundcover with
edible fruit. Also contains medicinal berberine, found in several families
in this order.*

*Order: Rosales*

Family: Rosaceae

Genera: *Amelanchier *(5),* Aronia* (2),* Cercocarpus *(1),* Chaenomeles *
(1),* Crataegus* (4),* Cydonia *(1)*, Dryas *(1),* Fragaria* (5)*, Geum *
(2),* Malus* (3)*, Mespilus *(1)*, Potentilla *(1),* Prunus* (24),* Pyrus *
(2)*, Rosa* (5),* Rubus *(14),* Sanguisorba *(3)*, Sorbus *(4)*,
Waldsteinia *(1),* x Sorbaronia *(1)*, x Sorbocrataegus *(1),* x Sorbopyrus

Family: Cannabaceae

Genera: *Humulus* (1)

Family: Eleagnaceae

Genera: *Eleagnus* (2), *Hippophae* (2), *Shepherdia* (1)

Family: Moraceae

Genera: *Cudrania* (1), *Morus* (4)

Family: Rhamnaceae

Genera: *Ceanothus* (2), *Hovenia* (1), *Zizyphus* (1)

Family: Ulmaceae

Genera: *Celtis* (2), *Ulmus* (1)

Family: Urticaceae

Genera: *Laportaea* (1), *Urtica* (1)

*A classic Rosaceae, Asian pear or nashi (Pyrus spp.) has edible fruit.
This is an excellent family of edible fruits, but as they share many pests
and diseases, increasing omega-level diversity can help safeguard against
crop losses.
Within the broader Rosales order, the Eleagnanaceae, Rosaceae, and
Rhamnaceae contain all many of the actinorhizal nitrogen fixers.*

*Order: Sapindales*

Family: Anacardiaceae

Genera: *Rhus* (4)

Family: Sapindaceae

Genera: *Acer* (2), *Xanthoceras* (1)

Family: Meliaceae

Genera: *Toona* (1)

Family: Rutaceae

Genera: *Zanthoxylum* (2)

Not all of our nuts are in the Fagales. This is yellowhorn (Xanthoceras
of the Sapindales. A very important tropical fruit order featuring citrus,
mangoes and more, quite a bit more minor in temperate forest gardens.*

*Order: Saxifragales*

Family: Crassulaceae

*Genera: Hylotelephium (1), Rhodiola* (1), *Sedum* (3)

Family: Saxifragaceae

Genera: *Chrysosplenium* (1), *Darmera* (1), *Heuchera* (1), *Mitella* (1),
*Saxifraga* (1), *Tiarella* (1)

Family: Grossulariaceae

Genera: *Ribes* (10)

*Ribes: delicious diversity. From top left: gooseberry (R. uva-crispa),
josta (R. x culverwellii), red and white currant (R. sativum),
clove currant (R. odoratum), black currant (R. nigrum). Ribes is a very
important shade fruiting genus in forest gardens, while the
Saxifragaceae are useful as specialist nectary groundcovers.*

*Order: Solanales*

Family: Convolvulaceae

Genera: *Ipomoea* (2)

Family: Solanaceae

Genera: *Physalis* (1)

Native perennial ground cherry (Physalis longiflora) has a fruit used
as a vegetable like so many Solanaceae (tomato, eggplant, tomatillo, bell
pepper etc.). This order contains many important world vegetables (like
and sweet potato), though its importance to cold climate forest gardens
is relatively minor and confined to sunny clearings and early succession

*Order: Vitales*

Family: Vitaceae

Genera: *Vitis* (4)

Small superorder, supplying us with grapes and muscadines. Here’s a lovely
purple-leaf grape, a variety of the European grape Vitis vinifera.*

*A Challenge*

**Can you get a member of every one of these orders in your forest garden?
Can you add some more not listed here? How wide a net can you cast? Omega
diversity is not the only criteria we need, but, like emphasizing native
species, it can help bring some underutilized species to our attention.
Dave and I determined that omega diversity was important enough to guide
our species selection, and we hope it will do the same for you. Enjoy!

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