The lessons to be learned from La Niña

Sunday, December 4, 2011

It will be a long time before we see a La Niña as strong as last spring, but we do have some of the same problems every spring that mimic those of 2011

by PAT LYNCH

Ontario producers did a great job in coping with this spring's wet weather. Many thought it was just an unusual spring and adjusted. 

But it was not just an unusual spring. Spring 2011 endured the strongest La Niña effect since 1919. La Niña, which is caused by a change in the trade wind circulation, was responsible for the extra rain in Australia last year, seriously affecting the wheat harvest. It was also responsible for starting the drought in Texas and the extreme weather through the southeastern United States this spring.

The weather forecasters told us we would have a strong La Niña and a wet spring season along the Eastern Seaboard and Ontario. If you knew it was coming, would you have done things differently? 

Looking back at spring 2011 gives an opportunity to review your whole operation to find its weak points. It will be a long time before we see a La Niña this strong, but we do have some of the same problems every spring that mimic planting problems from 2011.

Some producers were able to plant more quickly than others. Quick early planting is the key to good crop production in Ontario. Every spring "he who plants first, wins" – usually.

There were acres planted on heavy soil that had to be replanted. For the rest, planting early pays off.

To get corn in more quickly, look at your whole operation. Figure out how many hours it takes you to plant. In most years, you have 100 hours to prepare the soil, get manure out and plant without a yield loss. We did not have that this year. Many producers had zero hours of available planting time.

There was no big difference between soy stubble worked in fall 2010 versus ground not worked. I think that, on heavy soils, if you do some tillage in the fall on soy stubble, it will plant earlier. On lighter soils, it is best to leave soy stubble alone in the fall.

Corn ground worked with minimum tillage tools in fall 2010 was ready to plant earlier into soys than ground that was not worked. Ground worked with an older chisel plow or mould board plow took at least one more spring pass than ground worked with the reduced tillage systems.

A major problem this spring was weeds or volunteer wheat growing on land that was to be spring-planted. These plants kept the soil colder and wetter, resulting in poorer seedbeds. Sometimes, growers tried to work them down, but they came back as cultivator escape weeds. By the time they were sprayed, they were big and both hard and expensive to control.

This is one thing we could have done better this spring. Those weeds could have been sprayed earlier when the ground was too wet to do anything else.

Growers lost wheat yield by not getting nitrogen on soon enough, while those who applied nitrogen the previous fall were not affected. If you did not apply nitrogen to your wheat in fall 2011, make sure you get it on early.

There was a lot of tension this spring trying to kill weeds and spray a fungicide on wheat. At harvest, it was obvious that applying a fungicide helped yield more often than controlling weeds. Interesting that it was a weather pattern in the early 1970s that triggered a short-term increase in commodity prices. This may have happened again. BF

Consulting agronomist Pat Lynch, CCA (ON), formerly worked with the Ontario agriculture ministry and with Cargill.