© 1990 Heron Publishing—Victoria, Canada
Water movement in yellow-cedar seedlings and rooted cuttings: comparison of whole plant and root system pressurization methods
S. C. Grossnickle (1) and J. H. Russell (2)
1. Forest Biotechnology Centre, British Columbia Research Corporation, 3650 Wesbrook Mall, Vancouver, British Columbia, Canada
V6S 2L2 / 2. British Columbia Ministry of Forests and Lands, Cowichan Lake Research Station, Mesachie Lake, British Columbia, Canada V0R
2N0 / Received May 23, 1989
Summary
One-year-old yellow-cedar (Chamaecyparis nootkatensis (D. Don) Spach) seedlings and rooted cuttings were taken from cold-storage facilities and grown in aerated water in a controlled
environment room for 21 days. Root areas of seedlings and rooted cuttings were initially comparable, but after 21 days seedlings
had produced more than twice as much new root area as rooted cuttings. Water flow resistance through the plant-atmosphere
continuum decreased in both stock types over the 21-day period. In both seedlings and rooted cuttings, transpirational flux
density increased in a curvilinear manner as new root area increased. Root resistance to water movement decreased sharply
with increasing new root area up to 20 cm2 in both seedlings and rooted cuttings. Further increases in new root area did not result in further changes in root resistance
of either stocktype. Plant water movement was measured by both the whole plant and the root system pressurization methods
with results differing between the two techniques.
