Canola Stand Issues and Reseeding Decisions
Emerging canola fields can suffer damage from:
· Frost
· Wind
· Hail
· Seedling diseases
· Insects
If your plant stand is lower than expected, you may be asking: should you re-seed any part of your field? Use the questions below to decide.
1. Assess how many plants are left.
To start, aim for a minimum of 4 plants/ft2 before the 4-leaf stage. Canola can compensate and still branch out/fill in the canopy at this density. When plant density drops below 4 plants/ft2, weeds can outcompete, the canopy may not close properly, and the crop can be more vulnerable to heat and dry conditions during flowering.
2. Determine the cause of the damage.
· Is the damage from one event, like a strong wind or frost?
· Is it likely an ongoing issue, such as seedling disease, too much moisture, or possible herbicide damage?
· Is the re-seeded field going to be susceptible to the same damage?
If an on-going issue, re-seeding back to canola is likely not the wisest decision.
· Also, how bad is the damage? Are the remaining plants going to be able to grow through the damage with time? Is the growing point still healthy?
If the growing point is healthy, crop development may be delayed. However, the crop will still bloom, mature and be harvested sooner than if the area is re-seeded.
3. If you were to re-seed – what soil moisture are you seeding into?
Soil moisture is key for the re-seeded crop. It helps ensure quick and even germination and emergence. If the seedbed is dry, seed and seedlings can become stranded, resulting in slow or patchy emergence. If soil moisture is excessive, replanting may not be possible as fields cannot be travelled on. In both situations, if the existing stand still has the 4 plants/ft2 and can grow through the damage, it may be wise to leave the existing stand.
So, When Should I Re-Seed?
If 1) the plant population is low, 2) the damage has stopped and 3) there is enough soil moisture, then re-seeding makes sense.
If you are going to re-seed, remember to consider:
If you have an insurance contract with MASC, you will need to contact an adjustor to come and assess the field to make sure you are eligible for the re-seed indemnity. For MASC purposes and your own knowledge, a ‘check’ strip must stay in the original plant stand and condition in a representative area of the field. An area of 10 feet wide and the full length of the field, or as advised by the MASC agent. This check strip helps you decide whether to re-seed for future and/or similar situations.