Hypericum undulatum

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Hypericum undulatum
Hypericum undulatum var. undulatum.jpg
Hypericum undulatum var. undulatum, collected in Europe in 1910
Scientific classification Red Pencil Icon.png
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Malpighiales
Family: Hypericaceae
Genus: Hypericum
Section: Hypericum sect. Hypericum
Species:
H. undulatum
Binomial name
Hypericum undulatum

Hypericum undulatum, the wavy St Johns Wort, is a herbaceous perennial flowering plant native to western Europe and northern Africa. The specific name undulatum is Latin, meaning "wavy" or "undulated", referring, just as the common name, to the wavy leaf margins of the herb. The plant has a diploid number of 16 or 32.

Contents

Description

Hypericum undulatum grows 1.5–12 cm (0.59–4.72 in) tall, typically erect or decumbent with a creeping or rooting base. The herb typically has numerous to few narrow stems, each with four wings of tissue that bear black glands. The internodes are longer than the leaves, measuring 12–65 mm (0.47–2.56 in) long. The sessile leaves have elliptic to narrowly oblong blades measuring 6–40 mm (0.24–1.57 in) long and 7–14 mm (0.28–0.55 in) wide. The apex of the leaf is rounded, the margin is undulate, and the base is rounded or cordate. The leaves have pale undersides and are thinly or thickly chartaceous. The leaves have three, occasionally four, pairs of main lateral veins that arise from the lower quarter of the midrib, as well as a dense tertiary reticulation. Leaves have pale, dense laminar glands and black, close intramarginal glands that are irregular in size. [1]

The inflorescence of the herb is forty-flowered and arises from one to three nodes, with the ascending or horizontal flowering branches arising from up to six nodes. The lax inflorescence is predominantly cylindrical to subcorymbiform. The pedicels are 1–2.5 mm (0.039–0.098 in) long and the lanceolate, entire bracts and bracteoles are 2–4 mm (0.079–0.157 in) long. The star-shaped flowers are 12–17 mm (0.47–0.67 in) wide and are ellipsoid and obtuse while in bud. The five unequal sepals are 3–5.5 mm (0.12–0.22 in) long and 1–1.8 mm (0.039–0.071 in) wide and are erect in bud and fruit. The sepals each have five to seven veins and six to twenty black punctiform laminar glands. The five bright yellow petals of each flower are tinged with red dorsally and are 7–10 mm (0.28–0.39 in) long and 3–4 mm (0.12–0.16 in) wide, typically about twice the length of the sepals. The petals are obovate to oblanceolate and bear few punctiform laminar glands. Flowers have 25 to 40 stamens, the longest of which measure 5–8 mm (0.20–0.31 in). The trilocular, ovoid ovaries are 2–3.5 mm (0.079–0.138 in) long and 1–1.5 mm (0.039–0.059 in) wide. The ovoid capsules are 5–8 mm (0.20–0.31 in) long and 3.5–4 mm (0.14–0.16 in) wide. The cylindrical, yellow-brown seeds are 0.6–0.8 mm (0.024–0.031 in) long. [1]

The plant flowers in August and September and seeds germinate in the spring. [2]

Taxonomy

Hypericum undulatum occurs in two principal varieties: H. undulatum var. undulatum and H. undulatum var. boeticum. The majority of the species, H. undulatum var. undulatum, has narrow, undulated leaf margins and reddish flower buds, but a population in Sierra Nevada has flat leaf margins and untinged leaves. This population, named H. boeticum by Pierre Edmond Boissier, has intermediate characteristics between H. undulatum and H. tetrapterum . However, the broad leaves and inflorescence resembling H. tetrapterum in H. boeticum is interpreted as parallel development between the two species; the petals and leaves of the species represent a reversion rather than an intermediate condition. The species H. boeticum is now treated as a variety of H. undulatum rather than a separate species, but certain scattered populations of true hybrids do occur in the Iberian Peninsula. [1]

Distribution and habitat

Hypericum undulatum grows in non-calcareous fields and marshes, stream banks, fens, and acidic bogs at elevations from sea level to 2,700 m (8,900 ft). The plant prefers wet areas with lateral water movement. [2]

Hypericum undulatum occurs in far western Europe and northern Africa. In the United Kingdom the herb can be found in Cornwall, western Devon, Pembroke, Cardigan, and Merioneth, and in Ireland it can be found in western Cork. In continental Europe it occurs in Brittany, central and western Spain, and Portugal. In Africa it occurs in western Algeria, northern Morocco, Madeira, and Azores. The variety boeticum occurs only in extreme southern Spain with the variety undulatum occurring throughout the rest of the distribution. [1]

Ecology

Hypericum undulatum typically grows in vegetation dominated by mixtures of Molinia caerula , Juncus acutiflorus , and Juncus effusus . It also occurs in conjunction with a variety of other herbs, typically including Angelica sylvestris , Cirsium palustre , Filipendula ulmaria , Galium palustre , Lotus pendunculatus , Mentha aquatica , and Senecio aquaticus .

Population sizes of the herb can vary greatly, increasing especially following reinstatement of grazing or burning in overgrown sites. Decline of H. undulatum in localities is mostly due to habitat loss, typically resulting from agricultural intensification. Managing populations of the herb in grasslands involves grazing in the summer and occasional burning in the winter. [2]

Related Research Articles

<i>Hypericum</i> Genus of flowering plants known as St. Johns worts

Hypericum is a genus of flowering plants in the family Hypericaceae. The genus has a nearly worldwide distribution, missing only from tropical lowlands, deserts and polar regions. Many Hypericum species are regarded as invasive species and noxious weeds. All members of the genus may be referred to as St. John's wort, and some are known as goatweed. The white or pink flowered marsh St. John's worts of North American and eastern Asia are now separated into the genus Triadenum.

<i>Hypericum tetrapterum</i> Species of flowering plants in the St Johns wort family Hupericaceae

Hypericum tetrapterum is a herbaceous perennial plant species in the flowering plant family Hypericaceae. Its common names include St. Peter's wort, Peterwort, square stemmed St. John's wort, and square stalked St. John's wort.

<i>Hypericum mutilum</i> species of plant

Hypericum mutilum is a species of St. John's wort known by the common name dwarf St. John's wort. It is native to parts of North America and is present in other parts as an introduced species. It is an annual or perennial herb taking a multibranched erect form up to about 60 centimeters tall. The oval green leaves are one or two centimeters long and are covered in tiny glands. The inflorescence is a compound cyme of tiny flowers. H. mutilum subsp. mutilum and subsp. boreale have a diploid number of 16, and H. mutilum subsp. boreale can have a diploid number of 18.

<i>Hypericum olympicum</i> species of flowering plant in the St Johns wort family Hypericaceae

Hypericum olympicum, commonly known as the Mount Olympus St. John's wort, is a species of flowering plant in the family Hypericaceae found in the Balkans and Turkey and introduced to western Europe. It has been widely cultivated for centuries because of its large, showy flowers, which are far larger than those of most other species in Hypericum.

<i>Hypericum terrae-firmae</i> Species of flowering plant in the St Johns wort family Hypericaceae

Hypericum terrae-firmae is a woody perennial flowering plant in the St. John's wort family Hypericaceae. It is an endemic plant species of Belize.

Hypericum acmosepalum is a dwarf shrub in Hypericumsect. Ascyreia that is native to China and known as jian e jin si tao locally.

<i>Hypericum punctatum</i> species of plant

Hypericum punctatum, the spotted St. John's wort, is a perennial herb native to North America. The yellow-flowered herb occurs throughout eastern North America into southern Canada. The process of microsporogenesis carried out by this plant is prone to errors in chromosomal segregation. It has a diploid number of 14 or 16. Insects are attracted to the plant's pollen and the hypericin in the plant's leaves is toxic to mammals.

Hypericum cuisinii is a perennial herb in the genus Hypericum, in the section Adenosepalum. The herb has pale yellow flowers and occurs in Greece and Turkey.

<i>Hypericum canadense</i> Species of flowering plant in the St Johns wort family Hypericaceae

Hypericum canadense, known as Canadian St. Johns-wort, lesser St. John's wort, and lesser Canadian St. Johnswort, is a flowering plant in the genus Hypericum. It is a yellow-flowering annual or perennial herb native to North America and introduced to Ireland and The Netherlands. The specific epithet canadense means "Canadian".

<i>Hypericum phellos</i> Species of flowering plant in the St Johns wort family Hypericaceae

Hypericum phellos is a species of shrub or small tree in Hypericumsect. Brathys. The species is found in Colombia and Venezuela on scrubby slopes and moist woods.

<i>Hypericum denticulatum</i> Species of flowering plant in the St Johns wort family Hypericaceae

Hypericum denticulatum, the coppery St. John's Wort, is a perennial herb in the [[flowering plant family Hypericaceae. It is native to the Eastern United States. The species has two varieties, H. denticulatum var. recognitum and H. denticulatum var. acutifolium. The herb has a diploid number of 24 or 48.

<i>Hypericum majus</i> species of plant

Hypericum majus, the greater Canadian St. John's wort, is a perennial herb native to North America. The specific epithet majus means "larger". The plant has a diploid number of 16.

<i>Hypericum humboldtianum</i> species of flowering plant in the St Johns wort family Hypericaceae

Hypericum humboldtianum is a species of shrubby flowering plant in the St. John's wort family Hypericaceae native to Colombia and Venezuela.

Hypericum assamicum is a species of flowering plant in the St. John's wort family, Hypericaceae. It is endemic to India. Hypericum assamicum is one of two species of Hypericum in the section Hypericum sect. Sampsonia.

<i>Hypericum sechmenii</i> Species of plant

Hypericum sechmenii is a rare flowering plant in the genus Hypericum, in the section Adenosepalum, Hypericum huber-morathii group. It is native to central Anatolia, Turkey.

<i>Hypericum huber-morathii</i> Species of flowering plant in the St Johns wort family Hypericaceae

Hypericum huber-morathii is a flowering plant in the family Hypericaceae, section Adenosepalum, and the type species of the Hypericum huber-morathii group.

<i>Hypericum aucheri</i> Species of flowering plant in the St Johns wort family Hypericaceae

Hypericum aucheri, also known as Koramanotu in Turkish, is a herbaceous perennial flowering plant in the St. John's wort family Hypericaceae.

<i>Hypericum coris</i> Species of flowering plant in the St Johns wort family Hypericaceae

Hypericum coris, the heath-leaved St. John's wort, also called yellow coris, is a species of flowering plant in the family Hypericaceae, and is the type species of sect. Coridium. It is a low shrub, and it is found in Switzerland and northwestern Italy. The species has been a popular garden plant since the 18th century, valued for its long flowering period and for how well it adapts to cultivation.

Hypericum harperi, the sharplobe St. Johnswort or Harper's St. John's wort, is a perennial flowering plant in the family Hypericaceae. It is an aquatic herb native to southeast North America. H. harperi has a diploid chromosome number of 24.

<i>Hypericum vacciniifolium</i> Species of flowering plant in the St Johns wort family Hypericaceae

Hypericum vacciniifolium is a species of flowering plant in the flowering plant family Hypericaceae. It was first described by August von Hayek and Walter Siehe in the Ann. K. K. Naturhist. Hofmus. journal in 1914 from a specimen collected by Siehe in 1912.

References

  1. 1 2 3 4 Robson, Norman KB (1996). "Studies in the genus Hypericum L.(Guttiferae) 6. Sections 20. Myriandra to 28. Elodes". Bulletin of the Natural History Museum, Botany Series: 78.
  2. 1 2 3 "Hypericum undulatum". Online Atlas of the British and Irish Flora. Botanical Society of Britain and Ireland. Retrieved 10 October 2018.
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