Highlights of
1997-98
- The Cooperative completed its 15th year of operation!
- Andrew Bower completed his M.S. thesis entitled "Response of annual growth ring components to soil moisture deficit in young, plantation grown Douglas-fir in coastal British Columbia."
- Fatih Temel completed his M.S. thesis entitled "Persistence and age-age correlations of stem growth defects in Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco)."
- Moderate and severe summer drought treatments in the Seedling Drought Physiology Study had only a minor influence on diameter and height-growth of 2-year-old seedlings in the same season as the application, although 20% of the foliage and 18% of xylem conduits were damaged (xylem cavitation), on average, in the severe treatment.
- Mean fall cold hardiness in seedlings was less after the drought treatments than in the control. Seedling hardiness to summer drought and to fall cold are nearly unrelated genetically.
- Families differed widely in the percentage of xylem conduits in the second-year growth ring damaged by the severe drought treatment (5-59%), suggesting that this trait may be a useful indicator of drought hardiness in seedlings.
- Phase 1 of the Field Drought Study indicates that latewood width is increased in summers with higher soil moisture deficits. Thus, latewood annual growth ring components may be useful for assessing sensitivity of families to drought in sapling-age trees.
- Remeasurement of trees in the cooperative's Measurement Study indicates that early selection (age 12) for stem diameter branch size, and frequency of steep-angled branches (i.e., ramicorns and forks) would be nearly as effective as waiting to age 24 to make selections.
- A study plan was approved to develop microsatellite genetic markers for Douglas-fir, and then to apply these markers to investigate the factors influencing pollen contamination in seed orchards.
