Scientists working in woody environmental plant improvement have not taken advantage of new biotechnologies available to them. Such technologies could provide numerous opportunities for rapid genetic improvement. The meaning of the term biotechnology is evolving; for purposes of simplicity, it will be defined here as the following three processes: in vitro genetic selection, in vitro mutagenesis, and genetic engineering. These processes can be used to select genetically variant or mutant cells or to insert DNA into cells to produce genetically improved plants. In vitro genetic selection, often termed “somaclonal selection” (Larkin and Scowcroft, 1981), enables one to use techniques to select genetically variant cells and verify genetic variation in regenerated plants by biochemical or molecular techniques. The use of cell and tissue culture selection procedures results in regenerants with genotypic variation that originates from a single genotype. Genetic variation may exist within genetically heterogenous cell cultures either as pre-existing potential for genetic variation or as potential for genetic variability induced by the culture process. Selected cells can be regenerated and resultant variant plants can be tested for stability of the genetic alteration. Mutagenesis, in the context of plant biotechnology, is a classical means of altering plant genomes by applying either radiation or chemicals, coupled with regeneration of genetically altered plants in vitro. Examples of mutagenic agents are gamma rays, X-rays, ethyl methanesulfonate (EMS), 2,4-dichlorophenoxyacetic acid (2,4-D), and colchicine. Plants that result from use of these mutagens usually have random genetic mutations; the genetic mutations cannot be targeted. The applicability of chemical and physical mutagenesis is limited in biotechnology because lack of targeting results in low selection efficiency for a given target. In addition, many undesirable genetic characteristics may also be obtained by mutagenesis. Genetic engineering techniques often use recombinant DNA that is inserted into cells by Agrobacterium -mediated transfer, microprojectile bombardment (biolistics), electric current (electroporation), microinjection, and polyethylene glycol-mediated osmotic insertion. Protoplasts may be needed for the latter three techniques to enable DNA to cross the plasmalemma. Plant regeneration and clonal micropropagation are important requirements for using biotechnologies. These processes use tissue culture techniques to successfully apply biotechnologies to produce genetically altered plants. Plants can be regenerated by shoot organogenesis or somatic embryogenesis and then clonally micropropagated, usually by proliferation of axillary buds from shoot cultures. Micropropagation has been used successfully for commercial purposes with woody environmental crops such as Betula, Syringa, Malus, Prunes, Pyrus, Kalmia, Rhododendron, Rosa, and Amelanchier spp. (McCown, 1989). Many other species are produced on a smaller scale for profitable niches in national and regional markets.