Apple Rootstock Testing and NC-140

What Is NC-140?

NC-140 is a north central regional project, funded by the USDA, that  meets the guidelines presented by the North Central Regional Association (NCRA) in Guidelines for Multistate Research Activities. This project was established, under different names, in the 1960s by a group of horticultural researchers from across the United States and Canada to evaluate horticultural uses of rootstocks. In the mid 1970s, NC-140 was officially created and focused solely on apple rootstocks.

Prior to these national/international projects, rootstock evaluation was conducted by a number of universities, but results were difficult to compare due to differences in tree sources, scion cultivars, experimental designs, data collection, and tree management practices. NC-140 cooperators greatly reduced the number of years required to evaluate rootstocks by establishing uniform coordinated trials, so all factors influencing the results, other than soil and environmental conditions, were eliminated. Membership in NC-140 expanded into an international effort with about 22 cooperators in the United States, five in Canada, and two in Mexico.

What types of research do NC-140 cooperators conduct?

NC-140 was originally established to evaluate rootstocks under a range of growing conditions. However, over the years, the project has expanded to include rootstock evaluations for peach, pear, plum, sweet cherry, and tart cherry. Cooperators have also compared apple orchard systems, the effect of growing conditions and crop load on peach fruit size, the effect of rootstock and growing conditions on apple fruit size, and apple rootstock performance on replant sites.

Where can I learn more about NC-140 research projects?

NC-140 projects are listed at This site lists 13 apple plantings, six peach plantings, two cherry plantings, two pear plantings, and one plum planting that were established beginning in 1987. Included for most of the trials are the names of the trial coordinator and cooperators, along with a list of the rootstocks being evaluated and some details about the experimental designs.

Dr. Richard Marini, Penn State University

Dr. Wesley Autio, University of Massachusetts Amherst