Agriculture and Environment: Wheat

Better Management Practices: Burning Crop Residue

Wheat is grown in many parts of the world with relatively short growing seasons.

As a consequence, the stubble and crop residues do not have much time to decompose. Even when ploughed into the soil, straw can take several years to decompose, especially in climates with short, dry summers and long winters.

Burning wheat stubble
As a consequence, burning is a common practice in many parts of the world where there is an insufficient market for straw. Burning wheat stubble not only destroys valuable organic matter but also causes air pollution and releases carbon dioxide into the environment, therefore becoming an environmental problem.

Finding an alternate use
It is possible, however, to use stubble to improve the soil. If slow decomposition is an issue, it can be inoculated with decomposing microorganisms before it is ploughed under (Panfilo Tabora, personal communication).

As the wheat stubble breaks down it is converted into organic matter in the soil, which then binds with water, fertilisers, and pesticides, reducing the runoff from all of these.

Selling wheat straw
Increasingly, farmers in developed countries are selling their straw to particle and fibreboard manufactures, who use it to make engineered timber. By the early 1990s some wheat producers were making 15-25% of their net income from the sale of straw. At that time they were lamenting the dominance of shorter wheat varieties, which, while more storm- and drought-resistant, produce less straw.