By Garth Donald, Dynagra
So how important is a pre-seed burn off? That question gets asked to me and others in the industry all the time. It can be one of the most important things when it comes to certain weeds and density of weeds.
Let€™s start with a favourite of most farmers in Alberta, foxtail Barley. Since we have lost the use of Sundance we really don€™t have a post emergent solution. And because of zero tillage it can flourish because its root system doesn€™t get cut off by cultivator shovels anymore either. So the only real option is to give it a good shot of glyphosate in the spring. The only issue is you need to have the coverage to get through the old growth and get control of the plants so low water volumes in this case will hurt your control of the weed.
Another favourite is Cleavers. Cleavers can be both at winter and spring annual which make it a very hard plant for staging. I have seen fields where the grower did not do a preburn and when it came to post emergent spraying the winter annual cleavers were in the 10 to 15 whorl stage. So now what do you try and spray this with to try and control this monster? That is what I was saying to myself trying to figure out what to do. We didn€™t kill all of those cleavers and they seeded down to make a real mess for the future. This is when prepass was new to the market and with a little planning we could of had a fighting chance to control them with a post emergent herbicide. There are many more weeds like dandelion, narrow leaf hawk€™s beard, kochia and even flix weed that can be a problem for minimum and zero tillage operations. So this is why we can take advantage of the products that are available to us.
There are many products that we can use for a preseed burn off and they all have some fit in your operation. The big thing I tell my growers is just remember anything with a residual you can€™t plant canola into. So just make sure you know what you are spraying and where so we can have a less stressful spring.
Those are my thoughts,