This section is from the book "Handbook Of Hardy Trees, Shrubs, And Herbaceous Plants", by W. Botting Hemsley. Also available from Amazon: Handbook of hardy trees, shrubs, and herbaceous plants.
These prickly bushes are distinguished in their floral characters from allied genera by having a coloured bipartite calyx with the upper lobe of two teeth and the lower of three minute teeth. The spines of these shrubs are transformed leaves. The etymology of the name has not been satisfactorily explained.
1. U. Europaus. Furze, Gorse, or Whin. - The double variety of this plant is one of the most beautiful yellow-flowered shrubs we have, especially for planting in soil where little else would thrive. The Irish Furze (U. strictus) is an erect, more slender, less rigid form of this species.
3. U. Hispanicus. - A dense dwarf spreading bush in which the branches and pliable spines are very long and slender. The yellow flowers are produced very freely in Spring.