South America Calling

Hot and dry conditions, with no rainfall and temperatures over 40 degrees Celsius (104 degrees Fahrenheit) have been common during the last several months in central Brazil. True to the dry season, soil moisture has been wiped out of most areas. Rain has not fallen in most of these areas since April and producers are eagerly awaiting the start of the wet season rainfall to begin their soybean planting. They may not have to wait long.

But it has been a tough wait for producers there, as the lack of any rainfall in four or five months has led to terrible reductions in soil moisture, ground water, and river levels and increases in wildfires, heat and drought. The states of Mato Grosso, Goias, and Minas Gerais, which account for about half of the corn and 40% of the soybean production in Brazil remain in historic drought. Typically, these areas see a little rainfall from fronts moving north from Argentina and Paraguay in August or September, before wet season rains return in the final days of September. But this year there has been none. Many fronts have passed through southern Brazil and Paraguay but have fizzled out with their rain farther south. And the states of Parana, Mato Grosso do Sul, and Sao Paulo have only recently been on the receiving end of some better rainfall where first-crop soybean planting has only just begun.

Producers farther north in central Brazil will wait for soil moisture to start building up before significant planting of soybeans will commence, trying to avoid a situation where a quick 25-50 millimeters (1-2 inches) of precipitation would be enough for seeds to germinate, but not enough for them to find proper rooting.

The risk of a burned-up crop due to continued high heat and no subsoil moisture is too great of a risk to take, even if it means planting later than producers would like. They need wet season rains to start and be consistent, building up subsoil moisture, before they plant in earnest.

Consistency is not usually the case in central Brazil early on in the season. While the rains typically start filling in the last few days of September, they are usually spotty with increasing coverage and intensity through October before being rather consistent and reliable November through March. Usually, these rains start near the Amazon, and Mato Grosso in particular, and work their way eastward across the remainder of the country. Some areas in Goias, Minas Gerais, and Bahia sometimes wait well into October before the rains finally arrive, then have to wait longer for them to be consistent.

Mother Nature is going to do her best to ease the troubles of producers. At least, that is what is being forecast. Both the European ECMWF and American GFS models are pointing to spotty showers beginning in Mato Grosso on Sept. 26-27, exactly on the long-term average start date. Longer range versions of both models have showers being spotty the following several days, but then increasing Oct. 1, including across eastern areas of the region. The first 25-50 mm may come in early October and then increase from there. But these rains still need to fall, and producers will have to evaluate if they can plant their soybeans on time or wait until topsoils have enough water to reduce the risk of planting into the drought.

Delays to planting of the first-crop soybeans usually are not an issue for that crop. Consistent and heavy rainfall during the growing season, including the fill period in January, are more than enough to sustain and build a good soybean crop, no matter the planting date. The issue comes for the safrinha (second season) corn and cotton crops, which are planted in late January and February, immediately after the soybean harvest. Producers try to get corn through pollination before the wet season rains shut down in late April or early May.

If that occurs, then a decent corn crop can be made using the built-up soil moisture from the wet season to finish filling out the crop. If the wet season rains end early, which is a real concern during a building La Nina in the Pacific Ocean (cooler-than-normal sea-surface temperatures), then a late-planted corn or cotton crop can really suffer.

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John Baranick can be reached at john.baranick@dtn.com

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