Horsetail. Macrophotograph of a main stem,whorls of green branches,and leaf sheaths of a field horsetail Equisetum arvense. The main vegetative stem is produced from an underground rhizome,and the leaves are reduced to toothed scales (brown) at the nodes of the main stem. Whorls of green branches resemble needle- like leaves. Horsetails are the only living members of a primitive group of plants,the Sphenopsids,that predominated during the formation of the coal measures. Equisetum arvense is common throughout Britain in fields,wasteground and roadsides | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Nuridsany, Claude / Perennou, Maria |
Taille de l’image : | 2480 px × 3628 px |
Model Release : | Non requis |
Property Release : | Non requis |
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