Abiotic and biotic factors associated with pocket mortality of red pine (Pinus resinosa Ait.) in southern Ontario
Bibliographic record
Abstract
Red pine ('Pinus resinosa' Ait.) has been planted extensively throughout southern Ontario since the 1920s to restore marginal land to productive use, prevent soil erosion, conserve water resources, and provide timber, educational opportunities and recreation. In recent years, unprecedented rates of mortality in maturing plantations are challenging forest managers in their attempts to adhere to traditional management strategies and to realize expected economic benefits. Although earlier studies linked mortality with various causes, no comprehensive evaluation of red pine mortality was undertaken. This study investigated abiotic and biotic factors associated with pocket mortality at 12 plantations in southern Ontario. Trenches, 2 m deep, were dug in diseased and healthy areas of nine plantations exhibiting pocket mortality, and in three disease-free plantations. Below-ground assessments of soil physical characteristics and rooting were combined with above-ground measurements to compare healthy and diseased sites, plots and trees. Root disease pathogens, ('Armillaria ostoyae' and 'Heterobasidion annosum'), black pineleaf scale ('Nuculaspis californica'), drought and iron deficiency were associated with mortality. Rooting depth was greater on healthy sites than on mortality sites, but there was no significant difference between healthy and diseased plots on mortality sites, nor between living and dead trees in mortality plots, except on Armillaria root disease sites where living trees rooted more deeply than trees that recently died. The most notable and consistent difference between healthy and diseased sites was the alkaline C horizon of disease sites compared with the acidic C horizon of healthy sites. Armillaria root disease was the single most frequent biotic factor associated with decline and the rDNA 5S gene and IGS2 region of several ' Armillaria' spp. were sequenced, and an identification protocol was developed based on novel primers and RFLP analyses. RAPD and ISSR analyses of 'A. ostoyae' isolates from two sites provided evidence of carryover of 'Armillaria' from the original forest, through the agricultural period, to the current red pine plantation, as well as of recolonization of an area from which 'Armillaria' had presumably been removed through cultivation. An experiment investigating the contributions of soil type and genetics to rhizomorph production by 'A. ostoyae' isolates supported a greater inherent genetic component than from soil effects.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| 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 | 0.001 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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 source (direct Gemma or distilled Codex), 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".