Harvest options for multi-stage crops

August 9, 2018 – Issue 19

Non-uniform maturation is a common issue at harvest. This issue may be more pronounced in those areas that experienced abnormally dry conditions and intense flea beetle pressure this spring. Swathing remains the best and least risky option to manage uneven maturity.

Those set on straight cutting have three product options to consider as pre-harvest aids: diquat, saflufenacil (Heat LQ) and glyphosate.

Diquat has the latest application timing of 90% brown seed, which is when 90% of the seeds on the entire plant (not just the main stem) have changed colour. This product may run the biggest quality risk if applied too early, so it should not be used on crops with extreme variation in maturity. Reglone Ion from Syngenta is supported on shatter-tolerant canola only.

Saflufenacil has a labelled application rate of 60-75% brown seed, although BASF literature indicates 75% seed colour change (meaning 75% of the seeds on the main stem have a degree of colour change). Talk to your rep about the application timing they support. With an earlier application timing and both contact and systemic activity, this product is better suited than diquat to manage variable maturity.

Glyphosate has the earliest application timing of all of the products (labelled at when the crop has less than 30% moisture. Time this application around when you typically would swath (60% SCC). Having an earlier application window and strictly systemic, slow acting mode of action, this product is a good option for managing variable maturity in non glyphosate tolerant canola.

Leaving the crop standing to let the least-mature areas reach an acceptable moisture can also be a viable option with a pod-shatter tolerant variety. Shattering of the more mature areas isn’t as big of a concern with these varieties. Green plant material is likely to be present at the time of harvest and this can have an impact on harvest efficiencies.

Further reading:

PAMI Research Report “Straight Cutting Canola in Manitoba: A Comparison of Pre Harvest Aids”
PAMI Straight Cut Guidebook

Canola Watch