The association of such elements as the regional stations, NSSL, and the National Small Grains Collection with the NPGS is readily apparent, but many others are loosely associated. Even more important is that the system has no central administrative control, and hence it has limited capacity to identify or act on needed changes in program activities and germplasm management methods. Other assessments of the system have termed it a diffuse network (Council for Agricultural Science and Technology, 1984; Office of Technology Assessment, 1987). For example, the NPGS has no central office and staff, nor a definitive location in any USDA organizational structure. Laboratories and scientists, particularly within the ARS, may be considered to be part of the NPGS by virtue of their work on managing or enhancing germplasm.

The national system's collections contain more than 380,000 different accessions of some 8,700 species, including virtually all of the crops of interest to U.S. agriculture. The collections are managed at various laboratories and facilities located around the country. Sites or units of major importance are the

• National Seed Storage Laboratory located in Fort Collins, Colorado, for long-term, back-up storage of the NPGS collections. Of its more than 230,000 accessions, about 60,000 are not duplicated at other sites.

• Four regional stations in Pullman, Washington; Ames, Iowa; Geneva, New York; and Griffin, Georgia. They are responsible for the management, regeneration, characterization, evaluation, and distribution of the seeds of more than one-third of the accessions of the national system (i.e., nearly 135,000 accessions of almost 4,000 plant species).

• National clonal germplasm repositories at 10 locations in the United States, including Puerto Rico, for conserving and managing fruit, nut, and other species that cannot be held in seed collections (more than 27,000 accessions of nearly 3,000 species).

• National Small Grains Collection in Aberdeen, Idaho, which is responsible for more than 110,000 accessions of wheat, barley, oats, rice, rye, Aegilops (a wild species related to wheat), and triticale (a hybrid of wheat and rye).

• Interregional Research Project-1 (IR-1) in Sturgeon Bay, Wisconsin, which holds about 3,500 potato germplasm accessions, including cultivated forms of the white or Irish potato and more than 100 related wild species.

• Several crop-specific collections in universities or USDA labora-