At this time of year there is plenty of heather in flower. It is a flower much favoured by the bees and produces very good honey. There are several different plants which get lumped together and called heathers, but perhaps the commonest is Calluna vulgaris which to most people is heather but to some is known as ling. In France it is known as bruyyere.
It is a low growing perennial which becomes quite coarse and shrubby with time, but which rarely gets much above 50cm in height. It’s flowers are small and pink/purple in colour. It is what is known as a calcifuge which means it will only grow where the soil is acid. I think of it as a refugee from calcium. The opposite is a calcicole which is a plant that likes to grow where its is alkaline. In fact the vast majority of plants will grow anywhere as long as it is not too acidic or too alkaline.
The other characteristic of these plants is that their leaves are reduced to a very small, narrow shape and compressed into the stem so that you almost don’t notice them. This is an adaptation to avoid too much water loss. Heathers grow on heathland sites which can be quite dry in the summer but which can get quite wet and boggy in the winter. Both of these conditions require that the plant conserves water. You may wonder why wet boggy conditions would necessitate the conservation of water. The reason is that the plants can suffer from what is known as a physiological drought. What this means is that when the plant’s roots are in very waterlogged soil, there will be very little oxygen available. Roots need oxygen to live grow and function so with no oxygen they cannot take up water in the normal way and therefore they are, in effect, living under drought conditions, at least as far as the physiology or working of the plant is concerned.
In Britain, Calluna is the favoured food of grouse which as a game bird is often shot by hunters. Moorland which is used for grouse shooting is often managed to promote the growth of heather so as to increase the population of grouse and thus the income the landowner can realise from allowing shooting on his land. In fact the heather provides two things for the grouse – food, but they only eat the fresh young shoots and are not interested in the older tough woody stems and when the plants do get older and more bushy they provide good cover and an ideal place to nest. So a good grouse moor has both young heather and old heather. To achieve this a game keeper will burn off sections of the moor each winter and in the following spring new heather will quickly regenerate. After 8 to 10 years this will become old heather and will be good for nesting. So a pattern of burning will maintain both young and old heather to the delight of the grouse – until they get shot that is.
(Red Grouse photo from wikipedia’s page on Red Grouse)
There are several other species which are thought of as heathers, sometimes known as bell heather because their flowers are somewhat larger and bell shaped. Two common ones are Erica tetralix and Erica cinerea. They have slightly larger leaves and they stick out a bit more from the stem but still the leaves are quite small. The best way to distinguish them is that their flowers are much bigger and generally a richer purple colour.