Emergence timing and persistence of kochia (Kochia scoparia) in Manitoba fields
Bibliographic record
Abstract
This research addresses the ecological niche of Kochia scoparia (L,) Schrader (family: Chenopodiaceae), and how growers can close the ecological niche of K. scoparia in prairie cropland. The predictability of the spring emergence period of K. scoparia is a potentially exploitable attribute that may be applied to weed management. The emergence timing of K. scoparia was monitored, during the spring and summer of 2005 and 2006, in 12 fields (including high and low disturbance fields, a no-till alfalfa field and fields seeded to barley, beans, canola, corn, and wheat) in southern Manitoba, Canada. K. scoparia begins to emerge prolifically at only 50 cumulative growing degree days (GDD T base 0 C) and K. scoparia continues to emerge throughout the growing season into late summer. Soil samples taken in the fall from quadrats in which emergence was monitored reveal a very limited K. scoparia seedbank. This data supports other research which shows that K. scoparia seeds have little or no dormancy and a limited ability to persist in a seedbank. The effects of seeding depth (2, 10, 20, 40, and 80 mm) on emergence was observed, under controlled growth room conditions. K. scoparia seeds placed at the soil surface (2 mm) had the greatest emergence. Seeding depth reduced K. scoparia emergence significantly. The results from this study show that K. scoparia is a very early emerging seed-limited weed species with seed that cannot emerge from great depths. This information will facilitate K. scoparia control timing decisions and management for farmers and the data from this study can be used to create an emergence model for K. scoparia.
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 | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 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".