Cow Parsley
(Anthriscus sylvestris)
A familiar sight along roadsides, hedgerows and woodland edges, the short-lived perennial, cow parsley is tall with sprays of white flowers. Cow parsley is a fast-growing plant that is widespread and common throughout the UK, prefering shaded areas. This is the earliest flowering member of the carrot family. Cow Parsley is one of the few flowers that benefits from current road verge management since it likes high levels of nutrients (much like nettles). Sadly, this is at the expense of other more delicate species. Cow Parsley flowers first appear in April and they last through to the end of June. As these tall roadside wildflowers are dying back so several other umbellifers including Hogweed (Heracleum sphondylium) and Wild Angelica (Angelica sylvestris) are just coming into bloom.
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Cow parsley is a hollow-stemmed, tall downy plant growing to a metre or more in height. Its stems are striate (striped with parallel, longitudinal lines), furrowed, and green in colour with flushes of purple, with a diameter up to 1.5 cm, without spots - a good way to distinguish this plant from the similar, but very poisonous Hemlock. It has tiny hairs on the stem, rachis, and leaf stalks which are difficult to see but can easily be detected by touch. The petioles clasp the stem around the base and are broad and flattened with a downy margin. The rachis has a deep grooved channel. The leaf stalks and the stems often
turn a rich purple as the plants age. The main stem meets the roots in a single primary taproot which can branch further below the surface. From the roots lateral rhizomes can form. This wildflower can be either biennial or perennial, spreading rapidly in rich damp soil both by seed and via its rhizomes.
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The distinctive triangular, strongly divided, tripinnate leaves of this common wildflower are green and fern-like or feathery in appearance finely divided into many pointed, feathery leaflets, roughly 30 cm wide and 45 cm long, with an alternate leaf arrangement and with hair on the underside. The lowest primary division is much smaller than the rest
of the leaf. Young leaves of the plant are edible, but as it has so many very similar poisonous relatives, it is best left uneaten!
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Cow parsley in common with other members of the carrot family has large, flat umbrellas of small, white flowers, that are arranged in compound umbels typically 3cm to 6cm across, on short pedicels less than 1 cm long with a ring of short, stout hairs at the apex. There are downy oval bractioles with red pointy tips on the umblets, arranged on 4–10 rays 1.5–3 cm long. The rays are glabrous (smooth and hairless), with no bract present. Peduncles are similar in length to rays, more or less glabrous and furrowed. Each flower has 5 white petals, with larger petals near the outer edges of the florets, 2 stamens and 2 styles with an enlarged base forming a swelling at the apex of the ovary. Cow Parsley seeds are oblong, beaked and smooth, like elongated smooth teardrops; they gradually turn black as they ripen.
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Not to be confused with: fool’s parsley (Aethusa cynapium), which can be distinguished from cow parsley by the bracteoles (leaf-like structures) that are found underneath the flower head; upright hedge-parsley (Torilis japonica) which flowers later than cow parsley – from around July to September – and is smaller in size; wild carrot (Daucus carota) which at a distance may look like cow parsley but has an umbel that is made up of many florets, frequently with a purple one in the middle; and hemlock (Conium maculatum) which has leaves similar to those of cow parsley but sports a stem spotted with purple markings and is much bigger, growing to around two metres.
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Cow parsley is important for a variety of insects, including bees and hoverflies, as it is an early source of pollen. It is also a food plant for the moth Agonopterix heracliana and a nectar source for orange-tip butterflies.
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Hogweed
(Heracleum sphondylium)
This wildflower can be found almost anywhere, and is mostly found growing in damp ditches and hedgerows, along riversides, in open woodland, and in meadows and rough grassland. A native biennial, hogweed can grow to a height of anywhere between 4-6ft tall in favourable conditions. It grows especially well on moist, improved nitrogen-rich soils.
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Its wide lower leaves are pinnate and can be up to 60cm in length while its upper leaves are similar just smaller, with the same toothed edges. They are hairy, and serrated, and are divided into 3-5 lobed sections, the edges are typically round, unlike giant hogweed which are always extremely pointed.
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The main stem rises from a large reddish rhizomatous root, it is striated or ribbed and grooved, hollow, and has bristly hairs all over.
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​The flat-topped umbels (flower heads) of this hedgerow plant are seen throughout the Britain from June to September. The umbel can be up to 20cm across with clusters of small white or pinkish flowers, each containing 15-30 rays topped by individual flowers, these individual flowers contain 5 petals. The peripheral flowers have a radial symmetry (zygomorphic). The terminal umbels are flat-topped and the outermost petals are enlarged. ​The flowers are pollinated by insects, such as beetles, wasps and especially flies. The small fruits are schizocarps, winged and flattened, elliptical to rounded and smooth, up to 1 cm long. The seed dispersal is by wind.
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This plant can often be mistaken for the very poisonous Giant Hogweed (Heracleum mantegazzianum). The differences to be aware of are firstly the size, Giant Hogweed can grow as tall as 5 metres. The other clear difference is the leaves, on the Giant Hogweed they are very pointed with deep divides between them, while the leaves of the Common Hogweed are much more rounded. However, it contains some of the same phytophototoxic compounds (furanocoumarins), albeit at lower concentrations, and there is evidence that the sap from common hogweed can also produce phytophotodermatitis (burns and rashes) when contaminated skin is exposed to sunlight. Care therefore needs to be used when cutting or trimming it, to prevent 'strimmers rash'.
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The plant provides a great deal of nectar for pollinators. It was rated in the top 10 for most nectar production (nectar per unit cover per year) in a UK plants survey conducted by the AgriLand project which is supported by the UK Insect Pollinators Initiative. Hogweed attracts soldier beetles and many other insects during sunny weather. The leaves are commonly mined by the larvae of the leaf miner Phytomyza spondylii.
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