Factors influencing the availability of nitrogen in thinned and unthinned Douglas-fir stands in the central Oregon Cascades

1997 ◽  
Vol 93 (3) ◽  
pp. 195-203 ◽  
Author(s):  
Alejandro Velazquez Martinez ◽  
David A. Perry
Keyword(s):  
Douglas Fir ◽  
Factors Influencing ◽  
Oregon Cascades ◽  
Central Oregon Cascades

scholarly journals Evaluation of the provenance plot “Hrubá Skála” (Northern Bohemia) with grand fir at the age of 36 years

2017 ◽  
Vol 63 (No. 2) ◽  
pp. 75-87 ◽  
Author(s):  
Fulín Martin ◽  
Novotný Petr ◽  
Podrázský Vilém ◽  
Beran František ◽  
Dostál Jaroslav ◽  
...  
Keyword(s):  
Czech Republic ◽  
Norway Spruce ◽  
Coastal Region ◽  
Tree Height ◽  
Douglas Fir ◽  
Stem Volume ◽  
Silver Fir ◽  
The Czech Republic ◽  
The North ◽  
Oregon Cascades

The article aims to evaluate the research provenance plot established in 1980 in locality No. 214 – Hrubá Skála (in the north of the Czech Republic), where nine provenances of grand fir (Abies grandis (Douglas ex D. Don) Lindley) provided in the framework of the International Union of Forest Research Organizations project, and one provenance of grand fir, Norway spruce, silver fir and Douglas-fir from a standard commercial source are tested. We present the results of tree height, stem DBH, stem volume production and health status after 36 years. The results correspond with similar experiments in the Czech Republic and abroad and suggest that grand fir provenances from Vancouver Island (British Columbia, Canada) and the Washington (USA) State coastal region show the best production features, while the Oregon Cascades, Idaho and Montana provenances grow more slowly. Comparison with other tree species indicates that the production of grand fir at the investigated age exceeds the production of both Norway spruce and silver fir, and equalizes or gently exceeds even Douglas-fir.

Response of aboveground biomass increment, growth efficiency, and foliar nutrients to thinning, fertilization, and pruning in young Douglas-fir plantations in the central Oregon Cascades

1992 ◽  
Vol 22 (9) ◽  
pp. 1278-1289 ◽  
Author(s):  
Alejandro Velazquez-Martinez ◽  
David A. Perry ◽  
Tom E. Bell
Keyword(s):  
Leaf Area ◽  
Aboveground Biomass ◽  
Cultural Practices ◽  
Growth Efficiency ◽  
Douglas Fir ◽  
Nitrogen And Phosphorus ◽  
Area Index ◽  
Biomass Increment ◽  
Oregon Cascades

The effect of thinning and cultural practices (multinutrient fertilization, pruning) on total aboveground biomass increment and growth efficiency was studied over three consecutive 2-year periods (1981–1987) in young Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) plantations. Net aboveground biomass increment over the 6-year period averaged 14.5, 7.8, and 5.5 Mg•ha−1•year−1 for the high-, medium-, and low-density plots, respectively. Growth efficiency, after dropping sharply between leaf area indexes of 1 and 6 m2/m2, remained relatively constant up to a leaf area index of 17, the highest measured. Consequently, aboveground biomass increment continued to increase at leaf area indexes well above that at which the Beer–Lambert law predicts maximum light should be absorbed. Foliage analyses indicate that thinning improved nitrogen, potassium, and magnesium nutrition and increased the translocation of potassium from 1-year-old foliage to support new growth. However, fertilization increased foliar nitrogen and phosphorus contents only when coupled with pruning, suggesting that trees favor total leaf area over individual needle nutrition. Indications of potassium and magnesium limitations in this study are supported by other recent studies in Douglas-fir. Further work on the role of multinutrient deficiencies in this species is warranted.

scholarly journals Early Realized Genetic Gains for Coastal Douglas-Fir in the Northern Oregon Cascades

2004 ◽  
Vol 19 (3) ◽  
pp. 195-201 ◽  
Author(s):  
J. Bradley St. Clair ◽  
Nancy L. Mandel ◽  
Keith J. S. Jayawickrama
Keyword(s):  
Douglas Fir ◽  
Stem Volume ◽  
Early Assessment ◽  
Improvement Program ◽  
Genetic Gains ◽  
Large Numbers ◽  
Genetically Improved ◽  
Progeny Tests ◽  
Realized Genetic Gains ◽  
Oregon Cascades

Abstract Block-plot realized genetic gain trials were established for coastal Douglas-fir (Pseudotsuga menziesii var. menziesii) at five sites in the northern Oregon Cascades. The long-term objectives of these trials are to explore the growth trajectories and productivity of genetically improved stands and their relationship to predicted genetic gains based on performance in progeny tests. Measurements 5 years after planting provide an opportunity for an early assessment of realized genetic gains as compared to predicted gains and provide data for determining the number of replicates needed to detect statistically significant differences between improved and unimproved populations using large block plots. Results indicate that progress from selection and breeding of Douglas-fir is readily achievable, and realized genetic gains 5 years after planting are similar to those predicted based on results from progeny tests. Realized genetic gains were about 6% for height, 8% for diameter, and 28% for stem volume, compared to predicted genetic gains of about 8% for height, 7% for diameter, and 25% for stem volume. Large numbers of replicates (30–50) are required to detect statistically significant differences in height and diameter between improved and unimproved populations given genetic gains expected in a typical tree improvement program. West. J. Appl. For. 19(3):195–201.

scholarly journals Heritabilities, Intertrait Genetic Correlations, G x E Interaction and Predicted Genetic Gains for Acoustic Velocity in Mid-rotation Coastal Douglas fir

2011 ◽  
Vol 60 (1-6) ◽  
pp. 8-18 ◽  
Author(s):  
K. J. S. Jayawickrama ◽  
T. Z. Ye ◽  
G. T. Howe
Keyword(s):  
First Generation ◽  
Mixed Model ◽  
Genetic Correlations ◽  
Acoustic Velocity ◽  
Douglas Fir ◽  
Volume Index ◽  
Type B ◽  
The North ◽  
Stem Taper ◽  
Oregon Cascades

AbstractAcoustic velocity (AV) data from 7,423 coastal Douglas-fir trees drawn from 347 wind-pollinated families on 14 sites, from four first-generation testing programs in the north Oregon Cascades, were analyzed. Families were measured on two or four sites at ages 23 to 41 years from seed using the Fakopp TreeSonic standingtree tool. Height (HT) and DBH data collected at ages 15 and 16 from seed, from all trees in the four programs (95,795 trees, 955 families), were used to calculate volume index (VOL = HT*DBH2) and stem taper (TAP = DBH/HT). All traits were analyzed using multivariate mixed model analyses.Across-site individual narrow-sense heritabilities for AV2ranged from 0.24 to 0.40 among first-generation programs, compared to 0.12 to 0.23 for HT, 0.10 to 0.16 for DBH, 0.11 to 0.20 for VOL and 0.14 to 0.17 for TAP.Across-site type B correlations for AV2ranged from 0.85 to 0.95, compared to 0.62 to 0.83 for HT, 0.60 to 0.74 for DBH, 0.67 to 0.78 for VOL and 0.66 to 0.79 for TAP. AV2was negatively correlated with HT in three programs (rA= 0.17 to −0.28), and negatively correlated with DBH (−0.12 to −0.46), VOL (−0.05 to −0.44) and TAP (−0.09 to −0.40) in all four programs.Selecting the top 10% of the families sampled based on AV2gave predicted gains of 4.4% to 9.6% for AV2and −9.3% to 10.6% for VOL. The adverse genetic correlations between AV2and growth, and the losses in gain in AV2from selection based on growth, may be overestimated by suppression of slower-growing families in these older tests.

Sign in / Sign up

Export Citation Format

Share Document