As stated in (1. Seedling Variations) and (2. Seed Variation of Cultivated Plants), plants or trees grown from seed of the cultivated varieties are too variable for practical uses. The perpetuation of given varieties has led to the invention of many methods of propagation. The methods nearest to Nature, such as growing from cuttings of root or top, from sprouts, or by layering, have not been questioned by practical and experienced growers.
Budding and grafting are old methods in Europe, but the process was confined until recent years to changing the tops of hardy stocks by inserting buds or scions of desirable varieties. Root-grafting and commercial stock-budding are modern methods that have led to much discussion among American planters of trees, and in Europe the adverse decisions have been still more pronounced.