Wednesday, August 24, 2011

Wet, wet, wet

It's been very wet so far this year. We have had just under 500mm for the year to date, which makes it the wettest January-August since 1981. None of this rain has fallen in really big falls, just enough to keep things wet. As a consequece we have only sown about 10% of our winter crops, and they are struggling a bit. So it will be spring and summer crops this year.

I had the opportunity last week to look at a few crops south and east of my farm at Toogabbie. My view is that all the crops on the lighter sandy soils were doing well, but still suffering from the wet. They were showing Nitrogen and potash deficiencies, but should recover well with a bit of fertiliser. On the heavier loamy soils, crops that were sown early for grazing appeared to be growing well, but anything sown after the start of May was suffering.

What to plant?

Canola, Barley and Wheat are still worthwhile options as an early spring sown crop. In November 2009, we had a hot dry spring that absolutely hounded our crops. These are the type of conditions that we fear with a spring sowing. The hybrid canola seemed to handle it the best, followed by the barley. The winter wheat didn't like the heat at all, most likely because it was filling grain when it was over 30 degrees for a week. As we can't plant winter wheat now, we have bought some quick maturing spring wheat seed. I'd still like to see all these planted before mid September, (Late August would be better!) I think that 4t/ha is still possible for cereals and 2 t/ha for canola, however 75% of those yields would be more realistic. 50% would be roughly break even.

Maize and Sorghum have been discussed elsewhere in this blog. The only negative aspect of maize is the cost of the seed and the ability to dry grain. Sorghum is much later maturing for us, which presents drying problems and limits double crop options. Maize yields of up to 7 t/ha have been achieved in our trials. 5 t/ha would be a realistic target.

Safflower is a crop that may be a good option. In South West Victoria and S.E. South Australia, safflower is planted in paddocks that have been too wet to plant winter crops. Safflower is heat and drought tolerant (compared to wheat, barley and canola) and will also open up compacted soil. One bloke I met grows canola after safflower to achieve two years of grass control. In a wet year his canola yields much better after the safflower, however it can yield less in a dry year. 2 t/ha would be a target yield.

Sunflowers would be a really good option if it weren't for cockatoos. Another negative aspect is that broadleaf weed control options are limited, this also applies to safflower A good point is that they can be planted almost anytime in the spring, and still be harvested without having to be dried. A target yield would be 2 t/ha.

Field peas and Chickpeas are all potential options. Chickpeas don't like waterlogging or acid soils, but should otherwise yield as well as field peas and being worth more would be my preference in the right paddock. I think the best fit for chickpeas is planted in a maize stubble in mid-late winter. In a situation like this there would usually be no water logging problems, however this year my maize crop had a full profile of moisture at harvest time! Chickpeas could yield up to 3 t/ha.

Mungbeans are a possibility, planted perhaps in November. Broadleaf weed control is a issue. I have done some very small trials and reckon we can grow 1 t/ha.


Some cosiderations:
  • What if it turns dry next year? Double cropping after summer crops may not be possible.
  • What if we get a hot dry summer? Sorghum may significantly outyield maize.
  • What if we get a dry spring? Wheat, barley and canola will suffer.
  • What if it keeps raining? Crops grow well, a spread of maturity helps us battle through harvest and we double crop the summer crop stubbles.
It is importat to spread our risk. Wheat, barley and canola are the proven crops, and will top the list. Maize is the preferred summer crop. Sunflowers and safflower might be a good option in the right paddock, especially since they will be harvested when other crops aren't. A paddock of sorghum might be worthwhile. If I was going to take a punt on a legume it would be chickpeas. Mungbeans might go in a small trial somewhere.

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