Accurate dating of spruce budworm infestation using tree growth anomalies
Bibliographic record
Abstract
Spruce budworm feeding causes stem and branch deformities that alter the architecture of host trees in a permanent way, easily recognized several years after the defoliation event. Dating of budworm-related growth anomalies using tree rings provides a new means to reconstruct recent infestations of this defoliator. We tested this dendro-architectural method in the southernmost black spruce-lichen woodlands in eastern North America, which were affected by spruce budworm from 1976 to 1985. In these open stands, moribund black spruce trees support high loads of the epiphytic lichen Bryoria arranged in unusual patterns, a phenomenon known as black spruce decline. Because Bryoria was restricted to the dead and deformed parts of the trees, we hypothesized that the lichen only colonized those parts of the trees defoliated by spruce budworm. To test this hypothesis, we dated i) three types of growth anomalies associated with spruce budworm feeding (death of terminal buds, death of axes, and reiteration, i.e., production of new leaders and epicormic shoots) and ii) maximum extent of Bryoria on stem and branches of three spruce trees showing contrasting lichen cover patterns. All trees showed peaks of growth anomalies during periods of known spruce budworm activity. Also, Bryoria was almost exclusively located on internodes that were defoliated by spruce budworm. A model is also proposed to explain the different lichen cover patterns observed. Dating of tree growth anomalies (terminal bud mortality) has better resolution in time and space than tree-ring patterns to determine the first year of insect defoliation.
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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 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 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".