This section is from the book "British Wild Flowers - In Their Natural Haunts Vol2-4", by A. R. Horwood. Also available from Amazon: A British Wild Flowers In Their Natural Haunts.
The points first noted, the expansive-ness and openness of the meadows, will here again, as in the last section, be shown to have great significance in the life of the meadow plants when the question of fruit and seed dispersal is considered.
Amongst meadow plants there are few, except some of the large Umbelliferae, and such Composites as Burdock, that have large seeds or fruits. The hedgerow and woodland plants include many that are edible, and devoured by animals, especially birds, and these are heavy, e.g. Acorn; these are external agents.
But the two main external agents amongst meadow plants are the wind and animals, and in the latter case the seeds are not eaten, but catch in the wool or fur of passing animals. Thus the fruits of the Burdock have long hooks which catch in the wool of sheep.
Wind, however, plays the greatest part in the dispersal of seeds of meadow plants; for as a whole the seeds are small, and are thus easily blown away either directly or by some special device adapted to wind dispersal. All the grasses are dispersed in this way, as indeed they are pollinated also, viz. by the wind.
Great Burnet pollinated by the wind has its fruit dispersed in the same way. The gregarious plants are dispersed usually by the wind. The Composites generally, such as thistles with feathery pappus, the Dandelion and Goat's Beard with their parachute arrangement, disperse their fruit with the assistance of the wind.
The small seeds of the Orchids, those of the Campions, etc, with a sort of "censer" fruit, are jerked out of the capsules by the swaying of the fruit-stalks in the wind. The catapult arrangements of such plants as the Meadow Crane's Bill are devices of the plant itself. Of these the majority are hedgerow plants which, growing in sheltered spots, require such assistance to disperse them to a distance.
Clayey Meadows, Sandy Meadows. etc. - One of the most important factors in causing the distribution of plants is the character of the soil. There are some fifty geological formations which are distributed in different parts of the country, and these are responsible for the different types of soil. Of these there are six or seven, clay and loam, siliceous soils, sand, lime or chalk, humus, peat, saline soil.
The soil of meadows and pastures is of one of the first four types as a rule. Where peat or humus are present the vegetation is usually of moorland or heath type, and by the sea the salt marsh is largely saline.
Where a clayey meadow exists we shall find such plants as the Pilewort and the Cowslip. On a sandy meadow the clovers, especially White Clover, are common. A limestone or chalk meadow is indicated by such plants as Knapweed, Salad Burnet, Cicely, Bur Parsley, Purple Scabious, etc. Lady's Smock, Meadow Crane's Bill, Yellow Rattle, Spotted Orchis usually indicate sandy meadows with some peat and a little lime in the soil, as they are very often members of a marshy type of flora. In saline soils of salt marshes, which are converted into meadows by the sea very often, the Sea Aster, Wild Celery, Sea Milkwort, and many other maritime plants are found.
It will be very useful for pupils to draw up lists of plants found upon different types of soil in meadows and pastures, and to compare them.