Shoot elongation (s.e.) and associated phenological and morphological variables were studied in an 8-year provenance trial in Central Wisconsin. Geographical origin significantly affected s.e. and associated characteristics, except initiation date of s.e. Rate and duration of elongation contributed about equally to total s.e. Bud length affected rate but not duration of s.e. The pattern of weekly s.e. corresponded more closely to mean temperature than to mean precipitation.