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FLOWERS

ATTRACTIVE THOUGH MANY OF them may be, flowers are not produced to delight the human eye. Their role is strictly functional – they are the plant’s sex organs, there to produce sex cells and ensure the maximum chance of successful fertilisation taking place.

BASIC FLOWER STRUCTURE AND FUNCTION

In a few species, male and female sex cells are borne in separate flowers, or even on different plants, but in most cases they appear together within the same flower. Male sex cells are contained within pollen, tiny grains that are produced by structures called anthers and borne on slender stems referred to as filaments; collectively, anthers and filaments are referred to as stamens. The female part of most flowers comprises the ovary, containing the female sex cells, above which is borne the stigma (which receives the pollen) carried on a stem called the style.

Some plants, such as grasses and catkin-bearing shrubs, employ the wind to carry their pollen to others of the same species. Vast quantities of pollen are required to achieve a successful outcome with such a random process. Most other species adopt a more targeted approach and use the services of animals – insects in almost all cases – to transfer pollen. In exchange for a meal, in the form of nectar, insects inadvertently carry pollen on their bodies to the next flowers they visit; with any luck, a neighbouring plant of the same species will be visited while pollen still persists. In almost all species, flower structure has evolved to avoid self-pollination and to maximise the chances of cross-pollination – pollen being transferred to visiting insect pollinators and received from other plants by the same agents.

Bumblebees, and bees generally, are the classic insect pollinators. They visit flowers in search of nectar and unwittingly acquire a dusting of pollen, which is slightly sticky, on their hairy bodies; this is then carried to subsequent flowers they visit.

Cross-section through a typical flower, in this case a crane’s-bill.

Close-up of a stamen.

Close-up of the stigma, style and ovary.

WILD FLOWER IDENTIFICATION

SEASONED AND EXPERIENCED BOTANISTS are likely to approach the subject of identification by using definitive botanical works (floras) that rely on detailed keys, a thorough understanding of botanical terms, and a willingness to use descriptions rather than pictures to separate species. While this approach has scientific validity, in my experience it is not the way that the average floral enthusiast approaches the problem. Most tend to leaf through illustrated books to find suitable candidate species and then narrow down the field by scrutinising any closely related alternatives. This approach can succeed in most instances, especially if close care is paid to the detailed structure of the plant – leaves and fruits, as well as flowers – in addition to other factors such as flowering time, habitat preferences and distribution. I anticipate that this is how Complete British Wild Flowers will be used, initially at least, by most readers, although it will not take long for even the most inexperienced person to be able to detect similarities among plant family members, hence narrowing down the options at a stroke. Nevertheless, for absolute beginners, I felt it would be useful to provide a few pointers to lead in the right direction. I have concentrated on flower families where, in most species, there are sufficient similarities to justify generalisations. Strikingly unusual flowers, and species without large family ties, are not included in the following series of short cuts. I have used flower structure, such as the number of petals, as an initial guide. Note, however, that within several of the families identified, one or more rogue species may defy the family character and will not fall into the appropriate category. For example, although Tormentil is a member of the rose family (characterised by flowers with five petals), its flowers have just four petals.

SHORT CUTS TO FLOWER IDENTITY
3-PETALLED FLOWERS

WATER-PLANTAINS – equal-sized petals; white or pinkish petals; aquatic or marginal plants; see pp.

ORCHIDS – flowers comprising 3 petals plus 3 sepals, the latter often petal-like in colour and shape; the lower petal often takes the form of an enlarged or elaborate lip; see pp.

4-PETALLED FLOWERS

CABBAGE FAMILY MEMBERS – relatively small flowers; equal-sized petals; flowers often in groups; white, yellow or pinkish depending on species; see pp.

BEDSTRAWS – tiny flowers; equal-sized petals; flowers often in frothy heads; white or yellow depending on species; see pp.

SPEEDWELLS – relatively small flowers; unequal-sized petals; blue, purplish or white depending on species; see pp.

WILLOWHERBS – relatively small flowers in most species; equal-sized petals; flowers in open heads; pinkish, red or white depending on species; see pp.

POPPIES AND ALLIES – relatively large and crinkly, equal-sized petals; flowers usually solitary; red or yellow depending on species; see pp.

5-PETALLED FLOWERS

WATER-CROWFOOTS – equal-sized petals; flowers usually solitary; white petals; aquatic; see pp.

SUNDEWS – tiny flowers with equal petals; in spikes but usually only one flower opens at a time; bog plants with sticky, red leaves; white petals; see pp.

BUTTERCUPS – equal-sized, often shiny petals; flowers usually solitary; yellow; see pp.

ROCK-ROSES – equal-sized, crinkly petals; flowers usually solitary; yellow or white depending on species; see pp.

ST JOHN’S-WORTS – equal-sized petals; flowers in open heads in most species; yellow but marked with small black dots or streaks in some species; see pp.

ROSES AND ALLIES – equal-sized petals; flowers solitary or in open heads depending on species; white, pink or yellow depending on species; see pp.

SAXIFRAGES – equal-sized petals; flowers solitary or in open heads depending on species; white, pinkish or yellow depending on species; see pp.

MULLEINS – equal-sized or slightly unequal petals; flowers often in tall spikes; yellow or white depending on species; see pp.

LOOSESTRIFES AND PIMPERNELS – petals fused but 5 distinct and equal lobes present; yellow, red, purple or pink depending on species; see pp.

PRIMROSE – petals fused but 5 distinct and equal lobes present; yellow or pink depending on species; see pp.

MALLOWS – equal-sized petals; flowers solitary or in open heads; pink; see pp.

CENTAURIES – corolla fused but with 5 petal-like lobes; in clusters in most species; petals pink or yellow depending on species; see pp.

WOOD SORREL AND ALLIES – equalsized petals; yellow, pinkish or white depending on species; trifoliate leaves; see pp.

PINKS, CHICKWEEDS AND STITCHWORTS – equal-sized petals, often deeply divided; flowers usually solitary; white or pink depending on species; see pp.

PEA FAMILY MEMBERS – unequal petals arranged in a characteristic manner comprising a standard, a keel and wings; yellow, pinkish, purple or white depending on species; see pp.

CRANE’S-BILLS – equal-sized petals; flowers solitary or in open heads depending on species; pinkish, bluish or purple depending on species; see pp.

FLAXES – equal-sized petals; flowers usually solitary; bluish or white depending on species; see pp.

SEA-LAVENDERS – flowers funnelshaped; petals fused at the base; restricted to coastal habitats; bluish-lilac petals; see pp.

VIOLETS – unequal petals; spur present; blue, violet or white depending on species; see pp.

FORGET-ME-NOTS – petals fused but 5 petal-like lobes present; in open heads in most species; blue, pinkish or white depending on species; see pp.

TRUMPET-SHAPED FLOWERS

GENTIANS – trumpet relatively narrow; petals fused but with 4 or 5 pointed or rounded lobes; bluish, purple or pinkish depending on species; see pp.

BINDWEEDS – trumpet open and flared; white or pink depending on species; see pp.

BELL-SHAPED FLOWERS

BELLFLOWERS – flowers rather open with 5 lobes; blue or purplish depending on species; see pp.

HEATHERS – flowers typically small, rather tubular and usually pendent; pink or purple depending on species; see pp.

TUBULAR OR FUSED FLOWERS

EYEBRIGHTS – flowers 2-lipped; upper lip hooded, lower lip 3-lobed; white, marked with purple and yellow; see pp.

BORAGE AND ALLIES – 5 lobes present; flowers borne in spikes, curved in some species; yellow, pinkish, purple or white depending on species; see pp.

TOADFLAXES – flowers spurred and 2-lipped; upper lip 2-lobed, lower lip 3-lobed; yellow or purplish depending on species; see pp.

LOUSEWORTS AND COW-WHEATS – flowers 2-lipped; upper lip hooded, lower lip 3-lobed; borne in spike-like heads in most species; pinkish or purple depending on species; see pp.

FUMITORIES – flowers 2-lipped; pinkish or yellow depending on species; see pp.

FIGWORTS – flowers tiny, globular and 2-lipped; upper lip 2-lobed, lower lip 3-lobed; purplish or yellow depending on species; see pp.

LABIATES – flowers 2-lipped; lower lip often lobed, upper lip often hooded and toothed; borne in spikes in most species; whole plant often aromatic; wide range of colours seen in the different species; see pp.

BROOMRAPES – flowers 2-lipped; upper lip hooded, lower lip 3-lobed; flowers the same colour as rest of plant; borne in spikes; see pp.

MANY-FLOWERED HEADS OR FLOWERS IN CLUSTERED HEADS

UMBELLIFERS OR CARROT FAMILY MEMBERS – individual flowers comprising 5 tiny petals; flowers stalked and arranged in umbrella-shaped heads; white or yellow depending on species; see pp.

SCABIOUSES – individual flowers with 4 or 5 petals depending on species; borne in dense, domed heads; outer flowers often larger than inner ones; see pp.

DAISY FAMILY MEMBERS – numerous tiny flowers; arranged in dense heads in most species; inner disc florets appearing very different from outer ray florets in many species; wide range of colours seen in the different species; see pp.

FRUITS AND SEEDS

FRUITS FOLLOW IN THE wake of flowers and are the structures in which a plant’s seeds develop and are protected. In many cases, the shape and structure of these fruits, and often the seeds themselves, are designed to assist their dispersal, when ripe, away from the plant that produced them. A number of ingenious methods have evolved to facilitate this process: some seeds are carried by the wind; others attach themselves to the fur of animals; some even float away on water or have evolved to be eaten and digested by birds. The study of fruits and seeds is not only fascinating in its own right but in many instances the structure or appearance of a fruit can be a valuable aid to correct identification.

The burred fruits of Lesser Burdock readily become snagged in animal fur, travelling with the creature until the fruit finally disintegrates and liberates the seeds.

The hook-tipped spines on the fruit of Wood Avens catch in animal fur. Subsequently, they also help the fruit to disintegrate, as unattached barbs snag on objects and material that the animal rubs against.

The flowers of Common and Grey Field-speedwells are rather similar. Only by looking at the fruits (Common left, Grey right) can you be absolutely certain of any given plant’s identity.

Cabbage family members produce fruits known as pods, which vary considerably in terms of size and shape according to species. Those of Wild Candytuft, seen here, are particularly attractive.

Dandelion seeds are armed with a tuft of hairs – the pappus – that assists wind dispersal. While it remains intact, the collection of seeds and hairs is often referred to as a ‘clock’.

The fruits of Field Gromwell are hard-cased nutlets, designed to be resistant to abrasion and wear, allowing the species to grow as an arable weed, but of course only in the absence of herbicides.

Like other members of the pea family, the fruits of bird’s-foottrefoil are elongated pods.

The seeds of Elder are contained within luscious berries. These are eaten by birds and the seeds (protected by a coating resistant to being digested) are dispersed with the droppings.

The fruits of roses are fleshy and known as hips; inside these are seeds (dry achenes).

The fruit of the Common Poppy is a hollow vessel that contains thousands of minute seeds. When the fruit is ripe, holes below its rim allow seeds to escape when the plant is shaken by the wind.

In strict botanical terms, the fruits of the Raspberry are a collection of small drupes – each one a fleshy fruit that contains a hard-coated seed.

LEAVES

BEING THE MAIN STRUCTURES responsible for photosynthesis, a plant’s leaves are its powerhouse. They vary from species to species and come in a wide range of shapes and sizes. Their appearance is an evolutionary response to the plant’s needs, in particular factors such as the habitat in which it grows, the degree of shading or exposure dictated by its favoured growing location, and rainfall. In most instances, all the leaves on a given plant are likely to be broadly similar to one another, although size tends to decrease up the stem of a plant. However, to complicate matters, basal leaves can be entirely different in appearance from stem leaves. This applies to a number of species, notably some umbellifers.

In essence, leaves are thin and rather delicate structures. However, rigidity is maintained by a network of veins through which pass the ingredients required for photosynthesis, and the products of the process.

The intricate network of veins in a leaf is often best appreciated after autumn leaf-fall in deciduous species. Softer tissue decomposes before the veins themselves disintegrate, leaving striking leaf skeletons.

Leaf shape is not an infallible guide to plant identity, so its importance as an identifying feature is secondary to the appearance of flowers. There are many instances where entirely unrelated plants have superficially very similar leaves and great care must be taken when using leaf shape alone for identification. However, there are also plenty of instances where leaf shape is distinctive and diagnostic, or where it allows the separation of closely related plants that have superficially similar flowers. So it is worth paying attention to the variety of leaf shapes found among British wild flowers, some of which are shown right and overleaf along with the common descriptive name by which their shapes are known. Also shown are a variety of distinctive marginal features.

OVATE

LANCEOLATE

ROUNDED

POINTED-TIPPED

SPOON-SHAPED

LINEAR

ROUNDED-TIPPED

TOOTHED (DENTATE) MARGIN

HEART-SHAPED (CORDATE) BASE

PINNATE

PALMATE

LOBED MARGIN

CLASPING BASE

TRIFOLIATE (OR TREFOIL)

FINELY DIVIDED

HABITATS

WHEREVER CONDITIONS ARE SUITABLE for life then plants are likely to grow. Although some species are rather catholic with regard to where they grow, most are much more specific, influenced by factors such as underlying soil type, whether the soil is waterlogged or free-draining, summer and winter temperature extremes and so on. Consequently, where environmental conditions are broadly similar, the same plant species are likely to be found; where these communities are recognisably distinct they are referred to by specific habitat names. In Britain, many of our most distinct habitats owe their existence to past and present human activity, so they are classed as semi-natural in ecological terms.

DECIDUOUS WOODLAND

Woodlands of deciduous trees are found throughout most of the region. They are (or would be, if allowed to flourish) the dominant natural forest type of all regions except in parts of Scotland where evergreen conifers predominate. As their name suggests, deciduous trees have shed their leaves by winter and grow a new set the following spring. The seasonality seen in deciduous woodland is among the most marked and easily observed of any habitat in the region.

Almost all woodland in the region has been, and still is, influenced in some way by man. This might take the form of simple disturbance by walkers, at one end of the spectrum, or clear-felling at the other. Man’s influence is not always to the detriment of wildlife, however. Sympathetic coppicing of Hazel and Ash, for example, can encourage a profusion of wild flowers. In particularly rich locations, carpets of Bluebells, Wood Anemones and Wood Sorrel form the backdrop for more unusual species such as Early Purple Orchid and Greater Butterfly Orchid, Goldilocks Buttercup and Herb-Paris.

Centuries of woodland coppicing have inadvertently created the perfect environment for Bluebells to thrive. A carpet of these lovely plants is a quintessentially English scene.