National Clean Plant Network

NCPN logo

The Clean Plant Center Northwest (CPCNW) is funded in part through the United States Department of Agriculture – Animal and Plant Health Inspection Service (USDA-APHIS) National Clean Plant Network (NCPN). Two other agencies, the Agricultural Research Service and National Institute of Food and Agriculture, also oversee the National Clean Plant Network. In 2009, these three agencies signed a memorandum of understanding to “cooperatively support research, quarantine and outreach activities for the newly-organized NCPN.” Through the NCPN, clean plant centers were established throughout the nation to support specialty crops, including berries, citrus, fruit trees, grapes, hops, sweet potato and rose. Each specialty crop has a governing body, charter, and maintains close ties to industry through the ‘Tier 2 Committee’. The Tier 2 Committee helps set priorities for their specialty crop, as well as provide guidance regarding industry-specific issues, and recommend NCPN funding allocations. Tier 2 Committees are comprised of industry representatives as well as representatives from government and academia. The NCPN funds core activities in: networking and governance, plant introduction, diagnostics, therapeutics, and foundation planting.


The CPCNW has the largest Fruit Trees program in the National Clean Plant Network. With over 1,250 public and proprietary stone and pome fruit varieties, the CPCNW’s foundation (G1) planting stock represents an important source of clean plant material to the fruit tree industry. We hold a USDA-APHIS permit to test imported cultivars for viruses and virus-like agents; should pathogens be identified, we can then implement our virus therapy protocol. In addition to our clean plant services, we also coordinate the work of the Tier 2 committee.

NCPN Hop logo

The CPCNW is also the home for the National Clean Plant Network Hops program. At this time, we are the only Hops program in the National Clean Plant Network, serving as the sole source for clean plant material for the hop industry. In addition to our clean plant services, we also coordinate the work of the Tier 2 committee.


The CPCNW is one of five centers in the NCPN-Grapes program. Our clean plant process begins with aseptic meristem culture, with plants starting in a growth chamber, transitioning to the green house, and ultimately the screen house or foundation vineyard. We have over 350 varieties available for distribution in our screenhouses and foundation vineyard.