From Canola Council of Canada
Canola growers are encouraged to walk their fields a couple times a week — or more — until plants are firmly established and growing strong.
Small and vulnerable canola plants face many threats during their first three weeks. The crop may need your protection to get through these stages with its top-end yield potential intact.
Walk the fields a few times a week until the first few true leaves appear and the plants are growing rapidly. After that you may only need to scout once a week.
Start with a walk through the field taking a broad view for obvious emergence issues. Check that plants are green and healthy. If the plant stand has low emergence, uneven plant development, bald patches or unthrifty plants, this is when you start looking for clues as to why.
With flea beetles, the cause of damage is clear. But for uneven emergence, patchy growth and unthrifty plants, the cause can be difficult to pinpoint. Get a second opinion when necessary. You need to know what caused a problem before you can take effective corrective action.
Here are a few things to look for:
Differences row by row. Are some rows good and others thin? Or does it seems like strips of rows are poor while the rest are OK? These are likely the result of drill malfunction, or seeding too fast, with rear openers burying the front rows too deep. Check for seed depth and placement. Identifying these issues now will help to improve drill performance for next year.
Low emergence overall. If low emergence is fairly general throughout the field, seed may have been placed too deep, seeding rate may have been too low or seed quality was compromised. Large seed size combined with lower seeding rate and low seedling survival can result in thin stands. Consider this for next year.
Uneven growth staging. Large plants interspersed with late-emerging small plants can result from inconsistent seed depth from seed to seed. High fan speed on the drill may have caused seed bounce, which results in inconsistent seed placement. Worn openers and uneven residue cover are other possible factors.
More things to look for tomorrow.