establishment and early growth of black spruce (picea mariana [mill.] b.s.p.) in relation to selected nursery lifting and storage practices
abstract
problems associated with the establishment and early growth of overwinter frozen stored black
spruce {picea mariana [mill.] b.s.p.) seedlings led to research on the effects of selected nursery lifting and
storage practices on post-planting performance. the broad objective was to evaluate important
physiological and morphological response attributes of fall lifted, overwinter frozen stored, spring lifted,
cool stored, and freshly lifted 1v2 + 1 v2black spruce transplants during concurrent potting and field trials
established in may and june, 1987. the potting trials were conducted in a controlled environment
chamber under two soil water regimes (well-watered vs. water stressed). the outplanting trials were
conducted on a cultivated nursery soil and the scarified soil of a regional outplanting site. the nursery
trial included undisturbed (i.e. not planted, thinned in situ), control seedlings as an additional treatment.
the research conducted under controlled environment conditions indicated that the selected liftingstorage
treatments affect early plant water relations through interactions with both root growth capacity
and stomatal function. most importantly, the fall lifted seedlings exhibited prolific root growth but
showed poor stomatal control over transpirational losses. in contrast, the spring lifted seedlings showed
poorer root growth but maintained better stomatal control over transpirational losses. shoot-tissue water
relations determined using the pressure-volume technique varied between lifting-storage treatments, water
regimes, and potting times and often showed a lack of agreement between the selected parameters. pre-potting
osmotic potentials at full turgor and the turgor loss point increased between potting times for all
seedlings. in general, post-planting osmotic potentials were lower for the water stressed than well-watered
seedlings and increased with renewed bud and shoot activity. physiological response differed between the
fall and spring lifted seedlings under field conditions and generally compared with the results of the
potting trials. after one growing season, the undisturbed seedlings were clearly larger than any of the
outplants, particularly the spring lifted, stored seedlings. regardless of variations in physiological and
morphological response, all seedlings showed acceptable growth and survival after one growing season.
collections
- retrospective theses [1604]