It’s week three of this years exercise in botanical appreciation and, due to various commitments, plant-hunting this week has been focused entirely on urban areas.
Location dictates that the species featured this week are almost entirely weeds. Or at least those that the vast majority of the population may look upon as ‘weeds’. Weed, however, is a subjective term and these common and widespread urban plants are definitely interesting in their own unique way.
Sometimes, it is nice to appreciate the most tenacious of our nations plantlife.
Read more about the previous week of 365 Days of Botany here.
Day 15: Red Dead-nettle (Lamium purpureum)
A delightful, stingless nettle boasting hairy, heart-shaped leaves complete with toothed edges and a slightly corrugated texture. Common and widespread in the UK, the upper-most leaves of L. purpureum are purplish, as are its hooded flowers.
This is another plant with a rich history of use as a medicinal herb, with dried and fresh leaves used to treat cuts and stem bleeding. A tea made from the leaves of L. purpureum was also traditionally drunk to aid in the treatment of cold and flu.
Fun fact: whilst thought of as a native species, some sources suggest that the plant was in fact introduced to the UK alongside the development of agriculture.
Day 16: Common Whitlowgrass (Erophila verna)
A fairly inconspicuous plant of pavements and other bare places, E. verna is easily missed. The dull-green, slightly hairy leaves of this plant are lanceolate and displayed in a rosette. When in bloom, dainty white flowers sit atop leafless stalks, with each flower comprised of four petals. Each of which shows a deep cleft running almost halfway down its length.
Fun fact: an alternative name for this species, Nailwort, stems from its use in traditional medicine to treat ailments of the fingernail. Including, you guessed it, whitlows…
Day 17: White Dead-nettle (Lamium album)
The second dead-nettle to feature this week. Like other members of this family, L. album showcases typically nettle-like leaves: toothed, slightly hair and triangular. The flowers of this species are creamy-white and displayed in whorls on the upper part of the plant. A common species of urban areas, roadsides and hedgerows, it is native to Eurasia from Ireland in the West, to Japan in the East.
Fun fact: L.album was favoured as a source of chlorophyll and other plant pigments by Mikhail Tsvet, the inventor of adsorption chromatography.
Day 18: Common Knotgrass (Polygonum aviculare)
A relative of docks and buckwheat, P. aviculare is a sprawling plant with lanceolate leaves and small, greenish flowers fringed with white or pink. A common ‘weed’ of wasteground and urban spaces, it is native to temperate parts of the Northern Hemisphere but has spread around much of the globe as a result of agriculture.
The seeds of P. aviculare need light to germinate – the reason that this plant is often encountered on disturbed ground where long-dormant seeds have been brought to the surface.
Fun fact: this species is a traditional ingredient in a form of porridge consumed by Germanic peoples and has been found in numerous autopsies of peat bodies, including the famous Tollund Man.
Day 19: Procumbent Pearlwort (Sagina procumbens)
An easily overlooked (and tiny!) plant that I had mistaken for moss for many years. S. procumbens is a low, mat-forming plant species often observed spreading outward from a central tuft of moss-like foliage. Its flowers are tiny, sporting four or five small white petals backed by prominent sepals. Occasionally, and just to confuse things further, petals are absent from some of its flowers altogether.
Native to the Northern Hemisphere, S. procumbens has since spread far and wide and, carried on human footwear, has colonised a number of remote islands where it has become a damaging invasive species. Efforts to control the spread of this species on Gough Island are ongoing; while the population on the Prince Edward Islands is now thought to be beyond control.
Fun fact: This is said to have been the first plant on which Christ set his foot when he rose from the dead.
Day 20: Petty Spurge (Euphorbia peplus)
A common ‘weed’ of cultivated ground (and my own back yard), the leaves of E. peplus are oval in shape with smooth margins. Its clustered flowers are held in cup-shaped bracts and are yellow-green in colour. Unlike a great many plant species, these plants have no petals or sepals. Like other members of the Euphorbia family – including those popular as house plants – the plant, when damaged, exudes a sticky white latex that can irritate the skin.
This species is native to most of Europe, Africa and Asia but has since been introduced to to Australia, North America and New Zealand where it is considered a noxious weed.
Fun fact: The plant’s sap is toxic to rapidly replicating human tissue, and has been used as a traditional remedy for skin lesions.
Day 21: Common Groundsel (Senecio vulgaris)
Step outside, glance along your street and I dare say you will encounter Common Groundsel – it is one of our commonest urban plants, equally at home among pavement stones as it is in our carefully tended flowerbeds.
The stems of S. vulgaris are often purplish in colour, and its shiny, green leaves feather-like in appearance. Pinnately lobed, if I were to use the correct terminology – basically, they’re not too dissimilar to oak leaves. Its clustered, tubular flower heads are yellow and are flanked by black-tipped bracts.
Fun fact: the name Groundsel is derived from the Anglo-Saxon groundeswelge, meaning ‘ground swallower’. This thought to relate to the rapid way in which the plant spreads.