Flax is a wimp.
That’s why weed and disease control and fertility are key to getting a good yield, says Anastasia Kubinec, Manitoba Agriculture, Food and Rural Initiatives’ (MAFRI) oilseeds specialist.
“Flax hasn’t had the genetic improvement like canola,” she told those attending the 16th annual Crop Diagnostic School organized by MAFRI and University of Manitoba here at the university’s Ian N. Morrison Research Farm July 5.
In one plot with 570 green foxtail plants per square metre, almost none of the flax that had been seeded survived.
A University of Manitoba study conducted in the 1980s showed flax yields were boosted 500 per cent if weeds were controlled instead of allowing them to cover 90 per cent of the ground, Kubinec said.
Buctril M is one herbicide option in flax but shouldn’t be applied 48 hours before or after temperatures hit 28 C or higher. Applying the weed killer under hot, humid conditions can cause flax plants to bend over, Kubinec said.
Treflan can be fall applied to control Group 1-and 2-resistant green foxtail in flax.
Nufarm’s new pre-emergence herbicide Authority controls Group 2-resistant kochia and many other weeds, however there are factors that restrict its use in certain areas. Soil pH, organic matter and texture affect the application rate and in some cases prevent its use.
And there are recropping restrictions, including a 24-month wait from the time Authority has been applied in a field before canola can be seeded.
Pasmo is a disease, similar to septoria in cereals, which reduces flax yields, Kubinec said. It can be controlled by the fungicide Headline, which will boost yields, but also allow flax plants to reach normal maturity, which is around 110 days. Pasmoinfected plants will mature in about 105 days, Kubinec said.
Flax is often planted later in spring and when it is, farmers need to consider the potential for frost in the fall before applying Headline.
“If you get frost on flax the seeds turn black and their value goes way down,” Kubinec said.
“Your yield may not be as good (if you don’t spray a fungicide) but you can actually sell your product for $20 a bushel instead of $5.”
“Ifyougetfroston flax,theseedsturn blackandtheirvalue goeswaydown.”
– ANASTASIA KUBINEC