Onopordum

Onopordum is a genus of about 40 species of thistles belonging to the family Asteraceae, native to Europe (mainly the Mediterranean region), northern Africa, the Canary Islands, the Caucasus, and southwest and central Asia. They grow on disturbed land, roadsides, arable land and pastures.

They are biennials (rarely short-lived perennials) with branched, spinose winged stems, growing 0.5-3 m tall. In the first season they form a basal rosette of gray-green felted leaves and rarely a few flower heads. In the second season they grow rapidly to their final height, flowering extensively, and then die off after seed maturation.

The leaves are dentate or shallowly lobed to compound with several pinnatifid or deeply cut leaflets, and strongly spiny.

The terminal flower head is typical for thistles, a semi-spherical to ovoid capitulum with purple (seldom white or pink) disc florets. There are no ray florets. The receptacle is glabrous with dentate margins. The tube of the corolla is slender, sac-shaped and symmetrical. The anthers have awl-shaped outgrowths on the top. The capitula have several overlapping rows of leathery basal simple linear-lanceolate spines. These are smooth to slightly pubescent.

These plants propagate only by seed. The seed heads mature in mid-summer, releasing their seeds. The fruit is a glabrous achene, 4-6 mm long and with 4-50 ribs. The pappus consists of many rows of simple, fine to minutely rough hairs, united in a circular base.


Some species of Onopordum have been introduced as ornamental plants in the temperate regions of North America and Australia, where they have become naturalised in the wild. In most of these countries, these thistles are considered noxious weeds, especially in Australia where a biological control program has been set up


Selected species
Onopordum acanthium (Cotton Thistle, Scotch Thistle, Scottish Thistle, Spear Thistle) is a flowering plant in the Family Asteraceae. Other common names include, Scotch Thistle, and Scotch Cotton Thistle. Native to Europe, North Africa and Asia, it is a vigorous, biennial with coarse, spiny leaves and conspicuous spiny-winged stems.
The flower of the Scots' Thistle has been the national emblem of the Scots' nation since the reign of Alexander III (1249 - 1286) and was used on silver coins issued by James III in 1470.

Onopordum illyricum is a species of Onopordum. It is native the southestern Europe, but has been introduced into Australia and California, where it has become a noxious weed.

Onopordum tauricum (Taurian Thistle)

Onopordum macracanthum

Onopordum messeniacum

Onopordum corymbosum

Onopordum davisii

Onopordum nervosum

Onopordum majorii

Onopordum nivescens

Terminalia

Terminalia is a genus of large trees of the flowering plant family, Combretaceae, comprising around 100 species distributed in tropical regions of the world. This genus gets it name from Latin terminus, referring to the fact that the leaves... more >>>

Acaena

Acaena is a genus of about 100 species of perennial herbs and subshrubs in the Rosaceae, native mainly to the Southern Hemisphere, notably New Zealand, Australia and South America, but with a few species extending into the Northern Hemisphere,... more >>>

Vinca

Vinca (from Latin vincire "to bind, fetter") or Periwinkle is a genus of five species in the family Apocynaceae, native to Europe, northwest Africa and southwest Asia. The common name periwinkle is shared with the related genus... more >>>

Nerium oleander

Oleander (Nerium oleander), is an evergreen shrub or small tree in the dogbane family Apocynaceae. It is the only species currently classified in the genus Nerium.

Other names include Adefla, Alheli Extranjero, Baladre,... more >>>

Gerbera

Gerbera is a genus of ornamental plants from the sunflower family (Asteraceae). It was named in honor of the German naturalist Traugott Gerber, a friend of Carolus Linnaeus.

It has approximately 30 species in the wild, extending... more >>>