Grafting is a very specialized propagation technique in which shoots or buds from one plant are surgically implanted into another. The newest and most rapidly developing vegetative propagation technique is micropropagation. This involves a series of sterile laboratory techniques in which small sections of plant tissue are chemically stimulated to form multiple shoots and are then rooted. Rooted cuttings are the most common vegetative propagation method for native plants. Some species can be propagated either by seeds or vegetatively, and the decision depends on the objective of the outplanting project.
Quaking aspen is a good example.
Aspen seeds are very small and difficult to handle because they are enclosed in a ball of cottony material. Seeds can be cleaned relatively easily, but must be sown manually into growth containers because of their small size. If the objective is to retain the physical characteristics of a specific ecotype or clone, however, aspen can be propagated vegetatively from root sprouts, which are rooted and then transplanted to growth containers.