Plus-tree selection of black spruce in Northwestern Ontario for Superior growing space efficiency / by Laird Van Damme. --
Bibliographic record
Abstract
Plus-tree selection of black spruce [Picea mariana (Mill.) B.S.P.) \nbased on increment of wood volume per unit of crown (growing space efficiency) has the potential to improve yield per hectare and avoid biased \nselection of trees that have a competitive advantage in natural stands. \nIn 1981, and again in 1983, 200 and 400 trees from two 60 year-old upland \nblack spruce stands located in Northwestern Ontario were scored for \nvarious growth parameters, crown dimensions and competition indices. \nRegression analysis showed that the competition indices were poorer indicators of basal area increment (b.a.i.) than the crown parameters. \nThe crown parameter that best predicted b.a.i. was crown area (c.a.); \nr[superscript] 2 values of 0.45 and 0.57 respectively were calculated for the two black spruce stands although the slopes differed significantly. To \ntest the effectiveness of baseline selection of black spruce based on \nthe regression of b.a.i. vs. c.a., the top 10 trees were selected from \nthe second stand by this method and compared to each of the top 10 trees \nchosen by a height vs, age baseline method and a purely random method. \nOnly one tree was selected in common by each of the baseline methods. \nTrees selected by b.a.i. vs. c.a. baseline were far more variable in \ntheir size than those selected by height vs. age. Scale drawings and \nstatistical analysis of the selected trees did not reveal any easily identified \ncrop ideotype of black spruce plus-trees expressing growing \nspace efficiency. Wind-pollinated seed of the 29 selected trees was \ncollected and used to establish a short-term and a long-term progeny \ntest to investigate heritability of growing space efficiency. The \nshort-term test was conducted in a greenhouse over one growing season \nand included light intensity as a treatment, while the long-term progeny \ntest was planted in 1984 and included spacing as a treatment. \nDiscriminant analysis of Marks Lake progeny helped to identify a weak \ntrend where the tallest progeny came from short-crowned parents. Results \nof the short-term progeny test demonstrated strong family differences, \nstrong family x light interaction, but no selection method \ndifferences. Some of the family differences in the progeny could be \naccounted for by the maternal effect of seed weight, although after \nremoval of this effect by analysis of covariance, still no differences \ncould be detected between selection methods. Parent and progeny correlations for height and crown features were weak and often negative, \nwhich suggests heritability estimates for characters related to growing \nspace efficiency are likely to be as low as estimates for growth \nin general. The premature results of this study imply that if trees \nselected for superior growing space efficiency have inherent advantages \nin lower light intensities within mature stands, their juvenile \nprogeny do not express these qualities. Characters responsible for \ngrowing space efficiency are not heritable or have not yet expressed \nthemselves.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".