Using plant patterns to make identification easier in the field.
Ever since Carl Linnaeus devised his binomial classification system in the 18th Century, we have been actively using plant patterns to get to correct identification. Although DNA technology has come to supercede this somewhat, plants people throughout the world still use the floral patterns as a basis for deciding upon the plant family to which a plant belongs.
I will help you confidently and safely forage for more plants than you thought possible. Some of the terminology may seem strange when setting out on your foraging adventures, so there is a foragers glossary to help. Summary guides to basic leaf shapes and flower structure will act as an apperitif and help you digest this article.
A working knowledge of habitats and the best places to go foraging, either in the countryside or in towns and cities, will be invaluable. You can’t dodge the hours you need to spend building up your local knowledge, specific to that area, but certain knowledge is transferrable. To this end my guide to urban foraging distills a lot of my miles and hours tramping the streets and backwaters of towns and cities, silently hunting.
As well as showing you the best of our edible plants here in the UK, it is just as important that I guide you through the common poisonous plants that are found here.
At some point this may well lead you to ask the question “what is edible anyway?” The answer to that question is not as simple as knowing that a plant can be eaten. It is as important to know what time of year to harvest, and what stage in its growth development is it at its best for picking. A discussion on this can be found here.
Plant patterns aren’t just what we can observe though. One of the most important plant patterns is often unknowable until we engage our sense of smell. Plant chemistry and plant constituents are vital in helping us understand and know plants, It is often the smell of a plant that can be a clinching factor in positively identifying
The following common plant families are some of what I consider to be the most important for foragers to learn when out and about in the British Isles.
The mint family plant patterns
Annuals; biennials; herbaceous perennials; shrubs
One of the most well recognised and commonly used plant families in the world. Just about everyone knows some of these plants, and use them almost everyday in the kitchen or bathroom. So it makes sense to start our discovery about using plant patterns with the one of the best known patterns.
The mint family contains around 3,300 species in approximately 230 genera.
All plants in this family will be seen to have square stems. They have simple leaves, always opposite on the stems. The leaves appear at right angles to the previous pair.
Many members of this family are aromatic. The flowers consist of 5 united sepals (the calyx) subtending 5 united petal lobes. These flowers are two-lipped. Many species will be very aromatic and produce flower buds covered in essential oil glands.
Both lips of the flower are lobed; with 2 upper lobes and 3 lower lobes. They can be pronounced and wholly irregular lobes, as found on rosemary, or smaller more regularly lobed as will be found on marjoram.
The Flowers have between 2-4 stamens. This family all have a superior ovary. The fruits are small, and often referred to as nutlets.
Many of these plants have creeping underground stems (stolons), or creeping overground stems (runners). These adaptations help the plants quickly establish, colonise, and reproduce after injury, disturbance or grazing, because these stems are adapted to produce shoots and roots from every node.
The carrot family plant patterns
Annuals, biennials, herbaceous perennials
Possibly the most important plant family for a forager to know! This family contains some wonderful foods, powerful medicines, and deadly poisonous plants! There are approximately 3,600 species in 430 genera
The major pattern you will notice are the characteristic compound umbel flowers. Have a close look at any carrot family plant next time you see one in flower. You will notice the set of flower stalks emanating from a central point, very much like an umbrella.
This inflorescence is called an umbel, hence the former family sobriquet of umbelliferae. At the end of each of these stalks is a second umbel arrangement. Unlike a true umbel therefore, each compound umbel is always made up of smaller individual umbels.
Each of the small individual flowers boasts 5 petals, 5 stamens, 2 stigmas and an inferior ovary. The plants found in this country give us flowers that are generally white, with a few yellow, species. Occasionally the white flowers emerge with a pinkish tinge, and very occasionally the flowers are blue (Eringyium maritimum – sea holly).
Carrot family plants produce their foliage alternately spaced on the flower stems. The leaves are usually repeatedly pinnate, and typically in an overall triangular shape.
Some of the plants have very fern-like leaves, as can be found on sweet cicely (Myrrhis odorata), hemlock (Conium maculatum) and caraway (Carum carvi). Most have leaflets that are lobed, often deeply lobed.
Most of the plants have hollow stems, although the wild carrot (Daucus carota), and a other few plants, will have solid, pith filled stems. When it comes to identifying individual species, the shape of the petioles, together with arrangement and number of vascular bundles will assist tremendously in determining who’s who!
The corolla of certain species can contain larger outer petals, yet many species will produce five equal sized petals. The density and diversity of the shapes of the umbels become apparent with any amount of time spent studying them.
The fruits of the carrot family are technically schizocarps – dry fruits that split on maturity, into two separate parts. We colloquially call them seeds. A number of the family are strongly aromatic and have found use in the kitchen for millennia. Enjoy getting to know them more in this first part of a series called ‘Know your carrots’ !
The pea family plant patterns
Biennials; herbaceous perennials.
This is another large and well-known family of plants. A number of species are economically valuable, and have been eaten for millennia. As such, this family can be said to have widely contributed to Human evolution.
Around 600 genera and more than 13,000 species are currently documented from this family of leguminous, nitrogen fixing plants. Within larger plant families such as this one, various collections of similar looking genera are usefully placed into a number of ‘tribes’.
Therefore we can talk about the ‘clover tribe’ of trifoliate or trefoil species, and the mostly pinnate leaved vetches and peas from the ‘liquorice tribe’. These tribes and a few others all share a similar flower structure, so are further grouped together as the pea sub-family.
The major identification feature to look out for are the irregular flowers, which are distinctive by the unique shape. From the large garden pea (Pisum spp) and bean (Phaseolus spp) to the tiny flowers of wild clovers (Trifolium spp), all these plants show the same floral form.
Every one has a ‘banner’ petal (one petal with two lobes looking like two fused petals). This is found behind two ‘wing’ petals; with a further two petals (usually fused together) appearing as a ‘keel’ at the base.
At the base of the flower are 5 sepals, joined together (calyx tube). The flowers contain 10 stamens, 1 style, and a superior ovary. Typically the fruits of the pea family are set in a pod which splits upwards along the seam.
Species of interest to British foragers include alfalfa (Medicago sativa), the various clovers (Trifolium spp), lupins, (Lupinus spp), a number of vetches (Vicia spp), locust trees (Acacia spp), gorse (Ilex europaeus) and the sea pea (Lathyrus japonicus).
A number of plants in this family are toxic, including the Laburnum tree. Some species require careful preparation before consuming. You can read more on one of our most common pea family plants, red clover, in my foraging guide.
The lily family plant patterns
Herbaceous bulbous perennials
This is a large, varied, and often showy family of plants. Worldwide there are approximately 250 genera and 3700 species. Many of the plants we grow as ornamentals and many different flowers used in floristry are Lilies.
This family, similar to other families, can be usefully split into sub-families; each one a smaller collection of similar species. You may see reference in books to the ‘asparagus sub-family’, the ‘onion sub-family’, the ‘lily sub-family’ etc.
The majority of this family produce leaves with parallel veins. The leaves are simple and entire. Their foliage is often alternately arranged on the stem, and whorls of leaves are commonly found also.
The lily inflorescence is comprised of regular flowers, typically revealing their indistinguishable sepals and petals (often collectively called tepals).
These always occur in groups of 3 and are generally of the same shape, size, and colour. The flowers usually have 6 stamens, while the fused styles (pistil) are topped by a 3-part stigma.
Occasionally you could mistake lilly plants for similar looking flowers in the Iris family. However, the Iris family only have three stamens and their leaves are seen to be growing from the base of the plant in a flat plane. To confuse matters a little, certain genera in the lilly family contain an inferior ovary whilst others have a superior ovary.
Plant species of interest to the forager include the completely edible onion sub-family, containing a number of different garlic, leek, onion, and chive relatives. You may well be familiar with these onion family plants found in Britain: Bear’s garlic (Allium ursinum), 3-corner leek (Allium triquetrum), rosy garlic (Allium roseum), and crow garlic (Allium vineale).
Other notable edible species in the lily family that can be found in Britain include: Asparagus (Asparagus officinalis), the ‘bath asparagus’ (Ornithogalum pyrenaicum), day lilies (Hemerocallis species), the Century plant (Agave species), and yucca’s (Yucca species).
Some poisonous lily plants found in Britain include the snowdrop (Galanthus species) and the bluebell (Hyacinthoides non-scripta). Wild and bulb garlic have already been covered in my foragers monograph.
The rose family plant patterns
Herbaceous perennials; shrubs; trees
Worldwide, this family contains approximately 4,000 species in just 91 genera. Most of the species are herbaceous and woody perennials, shrubs and trees.
They are usefully split into ‘tribes’, especially the woody species, such as the cherry tribe of stone, or drupe fruits, the rose tribe of shrubs, and the pome fruits of the apple tribe of trees.
Herbaceous plants tend to produce their fruits as achenes, arising on a fleshy or dry receptacle, as in the strawberry or cinquefoils.
These well known plants typically have five separate petals in their flowers with numerous stamens, as in the brambles (Rubus spp) or apples (Malus spp).
Some members of the family have petals in groups of four, as found on the burnet’s, Lady’s mantle, and some cinquefoils. Always remember that where there’s a botanical law, it will likely be broken!
The rose family produce alternate leaves, which are characteristically oval in shape, and more often than not with serrated margins. Many in this family are known for having tiny leaf-like growths on the stems known as stipules.
Some plants, like meadowsweet (Filipendula ulmaria) and agrimony (Agrimonia eupatoria), will have small leaf-like growths visible on the mid-ribs. These are intercalary leaves, not true leaves.
Some rose plants have simple leaves, such as the cherry. Others have compound leaves (brambles). A number of species have pinnate leaves, including meadowsweet and the rowan tree. Medicinally they are known for their astringency, due to tannins. This makes them good wound herbs, especially for excessive bleeding, internally or during periods.
Some plants will have cyanide compounds present in leaves and fruit. These cyanogenic glycosides are medicinally valuable in small concentrations and are responsible for the almond scent and flavour in a number of the Prunus genus of plants.
The daisy family plant patterns
Annuals; herbaceous perennials; shrubs; trees
One of the largest plant families with approximately 1,100 genera and 30,000 species!
These plants are distinguished by composite flower heads borne on a single stem, as displayed by the sunflower (Helianthus annum).
What appears to be one big flower is actually a multitude of tiny individual flowers.
The petal-like appendages observed on many composite flower heads are technically ray florets. At the base of these florets you will find the usual floral reproductive structures.
The ray florets surround a circular array of numerous small individual flowers known as disk florets, which have no petals. The individual flowers are formed of a corolla tube. Many of the species in this family have flowers subtended by a group of overlapping leaf-like bracts, which in the thistle tribe is known as an involucre.
Typically, the flowers of wild family members found in Britain will have yellow or white ray florets, and yellow or white disk florets. Occasionally orange and blue colours will also be found, i.e. Chichorium intybus (Chichory).
Daisy family chemistry is fascinating (See plant chemistry handouts!). Some members of the family are aromatic, such as chamomile and mugwort, while others are not. One prevalent class of compounds found in the daisy family are sesquiterpenes. These aromatic molecules are somewhat volatile, though not as readily as monoterpenes, and plants with high concentrations of sesquiterpenes, often attached to lactones, as in Dandelion, wormwood and others, willl also impart bitterness.
This family are known for producing and storing their carbohydrate in the form of inulin, rather than starch. Inula helenium (Elecampagne), Jerusalem artichokes (Helianthus tuberosum), and burdock (Arctium lappa) are three plants known for their high concentrations of inulin
The leaves of the daisy family have no stipules. Many unusual foods such as the tuberous rooted Dhalia spp come from this family.
The mustard family plant patterns
Annuals; biennials; herbaceous perennials
Believed to contain around 370 genera and approximately 4000 species.
These plants are recognised by the flowers displaying the shape of a cross (hence their previous family name and the term ‘cruciferous plants’). Large numbers of the mustard family populate our towns and country.
Their flowers have 4 free petals and 4 free sepals, and typically 6 stamens (sometimes fewer) with a superior ovary. Certain plants have four stamens
Just before flowering you will likely notice a familiar ‘broccoli’ like flower bud on Brassica family plants. This will be apparent on all members of the family. Well known plants include: Shepherds purse (Capsella bursa pastoris), mustard (Brassica spp) radish, Raphanus spp, and bittercres species such as ladies smock (Cardamine pratensis).
Compare this family to the poppy family which also have four petals, a superior ovary, but many stamens; or even some ‘potentillas’ from the rose family, which again, have 4 free petals and many stamens. The willow-herb tribe from the evening primrose family (Onagraceae) also have 4 petals, but with an inferior ovary.
The Mustard family plants produce seed pods which split open to reveal spherical seeds. In terms of their chemicstry, species in this family often produce acrid, sulphurous compounds, giving them their characteristic hot, peppery taste. For foragers then, this is one of our finest and completely edible families.
The dock family plant patterns
Annuals; herbaceous perennials
One of our completely edible plant families. There are approximately 1200 species in just 48 genera.
These plants known for having individually small, green, triangular/heart-shaped flowers without petals, borne in clusters on long acutely-angled stalks. The simple leaves have un-toothed, (or entire) margins.
Aside from the well known and ubiquitous docks (Rumex spp), this family includes buckwheat (Fagopyrum esculentum), japanese knotweed (Fallopia japonica), common sorrel (Rumex acetosa), and rhubarb (Rheum rhabarbarum). This latter plant reminds us that just because one part of a plant is edible, does not mean that other parts of the same plant are edible!
The stems are often swollen at the nodes, a family trait giving rise to the name of Polygonaceae (literally meaning ‘many-knees’).
Many species will contain the substance oxalic acid, which imparts a distinctive sour, acidic taste.
The figwort family plant patterns
Annuals; biennials; herbaceous perennials
These plants are a little similar to the labiates and are closely related families.
The bisexual flowers are mostly irregular.
They have 4 or 5 sepals, often at least partially united, with 4 or 5 petals united as a tube.
The tube is usually 2-lipped with 2 lobes above and 3 lobes below.
There are usually 4 stamens in 2 pairs, but a fifth stamen is present in some.
The fruits are a many seeded capsule rather than nutlets as in the mint family. Well known plants from this family include the foxglove (Digitalis purpurea), speedwells (Veronica spp), and mullein (Verbascum thapsus).
The beetroot family plant patterns
Annuals; biennials; herbaceous perennials; shrubs
Although now widely placed into the Amaranth family, you will find reference to the Chenopodiaceae family in many books. There are approximately 2000 species and 165 genera in the Amaranthaceae family.
The Chenopodiaceae sub family are also known as the goose-foots. They are characterised by their tiny, individually inconspicuous flowers, often on branched stems. All members of the this sub family are edible, including Beetroot (Beta vulgaris), samphire (Salicornia spp) and qunioa (Chenopodium quinoa)
The dusty pollen betrays them as true flowers. Most family members have roughly triangular shaped leaves, often covered with a coating of shiny dusty dots.
When eaten raw they are often mealy to taste, and are reasonably high in oxalic acid.
If you spot a weedy plant in your area or garden without any obvious flowers, then it is likely one of the beetroot family.
The buttercup family plant patterns
These are notoriously tricky to define. This family has been called the most ancient of the plant families due to its floral arrangement, in contrast to the daisy family which is known to be the most recently evolved. ]
Within the family there are approximately 2,000 species in 43 genera
It has been written that the lack of a noticeable pattern is the most identifiable pattern of this family. Buttercups (Ranunculus spp) have their petals attached below a superior ovary.
They can have anything from 3-15 sepals and 0-23 actual petals. Most buttercups have bisexual flowers. A major property of the buttercups is the bitter, acrid taste they impart if nibbled on. The Aconitum and Delphinum genera contain very toxic terpene alkaloid molecules which act upon the central nervous system (C.N.S).