No spring-flowering tree is better known than the common yellow deciduous Laburnum (see Chapter 9.). It is really beautiful when in full bloom, but unsightly afterwards because of the slow decay of its inflorescence. This is the Laburnum vulgare of botanists, and there are many varieties of it, such as Alschengeri, Carlieri, grandiflorum, autumnale, giganteum, monstrosum, m. cristatum, quercifolium and Vossii. Alpinum, the Scotch Laburnum, does not differ greatly from vulgare; biferum, grandifloium, Parksii and Watereri are good varieties of it. Adami (syn. vulgare purpurascens and Cytisus Adami) is a graft hybrid, which has the interesting peculiarity of producing yellow and purple flowers separately on the same tree in some cases, but not in all. This is partly explained by the fact that the parents were Cytisus purpureus and the common Laburnum. The latter is used as a stock for budding and grafting the choicer Brooms. Ordinary soil.