The birdsfoot trefoils

The birdsfoot trefoils are leguminous flowering plants found growing in different habitats. The flowers are usually yellow. Several species occur in Malta. The common  birdsfoot trefoil, known in Maltese as qrempuċc tal-mogħoż,  is found growing in most habitats especially in fields, stony places, garrigue and roadsides. 

It grows throughout the Mediterranean appearing in winter and spring. Another common species is the edible birdsfoot trefoil known in Maltese as qrempuċ. This species is also found growing in a wide variety of habitats from late winter through spring. 

The grey birdsfoot trefoil, known locally as għantux tal-blat, also blooms in winter and spring. It is frequently found in stony places including close to the shore.

Trefoils belong to the leguminous plant family. This is a very large group in which we find a large number of plants which can be very different but are characterised by their flowers which usually have two large upper petals, two smaller lateral petals which form a wing and two even smaller petals which come together to form a keel. Well known members of this family are the clover, beans, peas and peanuts. The flowers of the carob tree, another member of the family do not have petals. 

Leguminous plants are known for their ability to fix nitrogen from the air thanks to a symbiotic relationship with certain bacteria found in root nodules. The ability to form this symbiosis reduces fertilizer costs for farmers and gardeners who grow legumes, and allows legumes to be used in a crop rotation to replenish soil that has been depleted of nitrogen.

Beans are one of the longest-cultivated plants, broad beans having been grown at least since ancient Egypt, and the common bean for six thousand years in the Americas.

Many modern dry beans come from European and African varieties of broad beans, but most of the kinds commonly eaten fresh come from the Americas, being first seen by Christopher Columbus during his conquest of a region of what may have been the Bahamas, where they were grown in fields.

Legume seed and foliage have comparatively higher protein content than non-legume material, probably due to the additional nitrogen that legumes receive through nitrogen-fixation symbiosis. This high protein content makes them desirable crops in agriculture and beans and other pulses are an important dietary source of proteins especially for vegetarians.

This article was published in The Times on 25.02.09.