Thorns, spines, and prickles

A thorn is a stinging structures on a plant, which sits on the site of an organ. Thorns are thus converted Stems, leaves, stipules, or roots. Your identity can be recognized by their position, partly by transitional formations. Thorns are always traversed by vascular bundles. This distinguishes them from the similar spines, but these are only formed as emergence of epidermis and cortex tissue. In common parlance the two terms are often used but reversed, has a rose is not the proverbial thorns, but thorns.

Spines serve the defense against herbivores and for climbing.

Types of thorns

• Sprout thorns are in local trees mostly remodeled short rung: examples are blackthorn (Prunus spinosa) and hawthorn (Crataegus ). Langtrieb thorns constitutes about buckthorn ( Rhamnus cathartica ).
• Journal of thorns is the barberry (Berberis vulgaris). Here sit the leaf spines on long shoots, arising from the axils of the thorns in the same year leafy short shoots. The cactus also form from leaf spines, but these are often called spikes. It can also only an outgoing leaf nerve form a mandrel in some thistles from the blade tips ( tetrahit Galeopsis ) the commons hollow tooth from the sepals. Which emerged from individual leaflets thorns in some climbing palms, about Eremospatha are called Akanthophylle.
• In addition to leaf spines ( Stipulardornen ) are paired, horny to woody stipules. They occur for example in the black locust (Robinia pseudacacia ) in acacia (Acacia ) and the Christ thorn ( spina- christi Paliurus ).
• Root thorns are rare and occur at about the aerial parts of sprossbürtigen roots of some palm trees as Acanthorrhiza, Cryosophila and Mauritia ago.

Thorns are very common in plants on dry sites before, during xerophytes and succulents. A characteristic example is the genus spurge ( Euphorbia ), occur in the various spike formation: common Nebenblatt thorns, next Langtrieb thorns (Euphorbia lignosa, Euphorbia gariepina ), sterile inflorescence stems ( Euphorbia horrida, Euphorbia enopla ) and leaf base thorns (Euphorbia hamata ).

Journal thorns of barberry (Berberis vulgaris)

For thorns reformed Encephalartos horridus leaflets from.

Young black locust with 15 mm long Stipulardornen (extension leaf spines ).

The thorns in art

Like the rose is a symbol of love, are the thorns (see oe confusion with spines ) those suffering dar. In the visual arts, they are also a common floral motif for injury and blood - see also the crown of thorns of Christ.

The poetry used thorns as such a symbol, but also has numerous puns and proverbs of the content. Some examples:

• Theodor Storm (July): "His ears lowers the grain / Red berry swells on the arbor "
• Phrase: " a thorn in his"
• Saying: " No rose without a thorn ".