Mountain pansy

The mountain pansy (Viola lutea) is, as its name suggests, a plant found in upland areas. Within the United Kingdom it is absent south of a line from the Severn to the Humber. It is a genuinely wild flower in that it is very difficult to get it to thrive in a garden setting, but it does well in grassy areas and on rock ledges in remote hilly environments, especially in lime rich soils.

The mountain pansy grows to a height of eight inches (20 centimetres) as a slender flowering stem. The leaves are oval when low down on the stem but narrower further up. They do not form a rosette at the base, but leaf-like stipules, divided into slender lobes, are found there instead.

The flowers, which appear from June to August, are usually single but not always so, as a single stem may bear up to four blooms. Flowering stems are sometimes sent up by creeping underground stems.

The fruit capsule splits into three parts to release the seeds when ripe.

Various colour variations have been noted, including yellow, blue-violet and red-violet. However, these variations do not occur within the same geographical area, such that yellow predominates in Derbyshire and Yorkshire and purple in Scotland.

© John Welford

Red campion

Red campion (Silene dioica) is found throughout Britain, preferring rich soils at the edges of woods or in hedgerows. However, it is also found in less conducive places, such as mountain ledges. Although a wild flower, it is often left alone when it gets into gardens because of its showy display of colour during the early summer.

Red campion throws up non-flowering shoots separately from flower stems. The plant can reach a height of 36 inches (90 centimetres). The lower leaves grow on long stalks.

The “dioica” part of the botanical name means “two houses”, because red campion plants only produce flowers of one sex or the other, which means that a plant growing in complete isolation cannot produce seed. Female flowers have no stamens and male flowers have a non-functioning ovary.

Whatever the sex of the plant, red campion produces a large number of bright red flowers in May and June. The petals are deeply divided and have an inner ring of white flaps. The brown sepals form a sticky tube at the base of the flower.

Although red campion is scentless, the related white campion does have a faint scent. The two types can hybridise to produce plants with pink flowers, and the hybrids will also be fertile. This can lead to a variety of shades from pure white to deep red.

© John Welford

Death's head hawkmoth

The death’s head hawkmoth gets its name from the markings on its thorax that look to human eyes like a skull. This is purely accidental, and does not appear to afford the moth any protection (unlike the “eyes” on the peacock butterfly), but that has not stopped the moth from acquiring superstitious significance as a harbinger of death.

For protection, the death’s head hawkmoth uses sound rather than appearance. It does so by forcing air out of its proboscis to produce a loud squeak. The caterpillars make a clicking sound if disturbed.

The death’s head hawkmoth belongs to the sphinx group of moth species that is found in Africa, Asia and Europe.

It feeds on honey which it takes from bee nests, although the caterpillars feed on potato and tomato plants.

Female moths lay single eggs on different plants. The caterpillars, which can grow as large as 12.5 centimetres long, have a prominent “tail” and are known as hornworms for this reason. They pupate underground.

© John Welford

Parasitic wasps

Parasitic wasps, such as the ichneumon wasp pictured here, have a life cycle that sounds horrific at first hearing, but they actually perform a great service to mankind by focusing their attention on species that we normally regard as pests for the damage they do to crops.

Parasitic wasps breed by laying their eggs inside other small creatures, such as spiders, aphids, caterpillars or other species of wasp. This is done by injecting the eggs through an ovipositor, or egg-laying tube.

When the eggs hatch, the larvae eat their way out of the host’s body, resulting in the death of the latter. As many as 3000 wasp eggs can be laid inside a host.

Some very small species of parasitic wasp lay their eggs inside the eggs of other species. The introduced eggs then divide many times before hatching, such that as many 150 wasps (all clones of each other) can emerge from a single host egg.

However, parasitic wasps do not always have things their own way. One species of parasite can become the host for a different species, and this can happen several times over in a process known as hyperparasitism.

The smallest known insect, the fairy fly, is a parasitic wasp that infects insect eggs. The fairy fly is only 0.2 millimetres long.

© John Welford

River water-crowfoot

The river water-crowfoot (Ranunculus fluitans) is commonly found in fast-flowing streams and rivers in England, Wales and southern Scotland. The main bulk of the plant is underwater with only the flower stems poking above the surface. The plant depends on the water being unpolluted so that sunlight can reach the tassel-like leaves. In turn, the presence of river water-crowfoot is a reliable sign that the stream is in generally good condition.

The stems of river water-crowfoot can be up to 20 feet (six metres) long. The tassels, which divide into narrow, hair-like segments, can be up to 12 inches (30 centimetres) long.

The flowers, which appear mostly in June, are white, about one inch (2-3 centimetres) across, and with overlapping petals, of which there can be eight per flower. The fruit heads are likewise held above the surface on stout stalks.

© John Welford

Opium poppy

It may come as a surprise to learn that the opium poppy (Papaver somniferum) grows wild in the United Kingdom, as it is widely assumed that this is a plant that is cultivated in the Middle East and countries such as Afghanistan, where its cultivation for heroin production is a major cause of the troubles in that country.

However, opium poppies can indeed be found throughout Britain, usually because seeds have escaped from gardens. It is not illegal to grow opium poppies, but you will break the law if you try to extract opium (in any form) from them.

The opium poppy grows upright to a maximum height of 36 inches (90 centimetres). The bluish-green leaves are broad-shaped with shallow-toothed lobes. The flowers, which are pink with dark centres, grow to seven inches (18 centimetres) across. They appear between June and August. The impressive flowers are the main reason why the opium poppy has been used as a garden plant. The seed capsules are globular and have a fluted cap.

The narcotic properties of the plant account for its botanical name “somniferum” , or “sleep giving”, Somnus being the Roman god of sleep.

The opium poppy has been used throughout recorded history for many innocent purposes as well as its less welcome applications. It should also be remembered that opium is the source of beneficial drugs, including codeine and morphine, as well as harmful ones such as heroin, although the latter was originally developed for medicinal purposes and gets its name because it was believed to be “heroic”.

Among the innocent purposes are the use of its seeds for flavouring bread and cakes, and the extraction of oil (from the seeds) that has a variety of culinary and industrial uses. It is the latex of the opium plant that is refined to produce drugs.

© John Welford

Northern yellow-cress

Northern yellow-cress (Rorippa islandica) is found throughout the British Isles, particularly on the edges of ponds and watercourses and in water meadows. It can withstand having its roots immersed in water during the winter but drying out in summer. It is sometimes encountered as a garden weed.

The plant grows erect to about 24 inches (60 centimetres) high, having a hollow stem. The leaves, which are deeply lobed, grow on stalks towards the base but without stalks higher up. The stalks half-clasp the main stem at their base.

The flowers, which appear from June to September, are small and yellow, being visited by small insects such as flies and hoverflies. The sepals and petals are the same length.

As the flower-stems grow higher, small oblong seed pods form in clusters below them, each seed pod being held on a stalk that is about the same length as the pod.

Northern yellow-cress is also known as Iceland watercress, but it is not an edible plant like its relatives, the white-flowered watercresses. There are several other varieties of yellow-cress that are found in Great Britain (e.g. creeping and greater) and these are also inedible.

© John Welford