After a mild winter, Bartlett on Old Home rootstock bloomed earlier and more uniformly than Bartlett on other rootstocks or own-rooted Bartlett trees. Normal blossoming time of the rootstock appeared to be unrelated to its influence on the bloom period of the Bartlett scion. Also, differences in time of bloom apparently were not associated with tree vigor. This research indicates that Old Home rootstock may be valuable in areas where production of Bartlett is limited by insufficient chilling.

Robert C. Campbell, Staff Research Associate, summarized the temperature records.