Plant 225

Plantago major Huds. (Plantaginaceae)


Greater plantain

Plantago major, one of the commonest plants in the British Isles, is typically found in trampled ground, waste places and grasslands on a wide variety of different soils. The rosettes of broadly spoon-shaped leaves, which are usually closely pressed to the ground, and the long spikes of tiny, greenish flowers are distinctive. There can be few garden lawns without an extensive, frequently maligned, plantain population.

Plantain is a classic camp follower and is widely naturalised outside Europe. Individual plants can produce up to 20,000 seeds. The seed coats secrete polysaccharide-rich mucilage on contact with water (myxospermy) which helps the seeds to contaminate grain crops or stick to passing animals.

Records from pollen cores show Plantago major appears in Nordic countries about the same time as crop cultivation was adopted, some 4,000 years ago. Plantain is thought to have been introduced to North America early in the seventeenth century, where it soon spread across the continent. Native Americans apparently called it 'white-man's footprint'; a reference to its occurrence wherever Europeans went. Ironically, Plantago means 'sole of the foot'; in this case a reference to the shape of the leaves.

Despite being an introduced species, it was extensively adopted by Native Americans into their pharmacopeia as a powerful wound-healing herb. The Graeco-Roman physician Dioscorides recorded similar uses for the plant in Europe, where it has been treated as a panacea for centuries.

Six varieties of Plantago major, based on leaf form and habitat, are currently recognised in the British flora. Further variation in plantain was identified as numerous monstrous, developmental mutants began to be cultivated in seventeenth-century gardens. Such mutants were particularly obvious in the flower spikes. In some cases, flowers become tufts of leaves. In others, unbranched wild-type flower spikes become extensively branched. These mutants fascinated the first Keepers of the Oxford Botanic Garden in the late seventeenth century. Today, developmental mutants of plantain are frequently found in populations treated with sub-lethal doses of herbicides.

During the 1920s and 1930s, investigations of natural variation and monstrosities in European populations of plantain were among the first studies of phenotypic plasticity and the genetics of developmental mutation in plants.

The genus Plantago, with nearly 300 species, has two main pollination syndromes: insects and wind. Plantago major is a wind-pollinated, outcrossing species. However, there are reports of selfing in plantain, which would help explain why some populations remain morphologically distinct despite long-distance pollen movement.

Further reading

Sagar GR and Harper HL 1964. Biological Flora of the British Isles. Plantago major L., P. media L. and P. lanceolata L. Journal of Ecology 52: 189-221.

Samuelsen AB 2000. The traditional uses, chemical constituents and biological activities of Plantago major L. A review. Journal of Ethnopharmacology 71: 1-21.

Stephen Harris