1Brandon, MB; 2Melfort, SK
Excessive crop residue accumulation at the surface of the field is a common concern of producers in the Parkland region of western Canada. The concern is that excessive amounts of accumulated surface crop residue will adversely affect seed germination and crop emergence due to excessively cold soil conditions. This research was conducted to compare the rate of decomposition for wheat, barley, canola, flax and pea residue in barley and canola crop canopies.
Decomposition of spring wheat, barley, canola, flax and field pea straw was measured from residue placed at the soil surface in cereal and broadleaf crop canopies at Melfort and Tisdale, Saskatchewan. The decomposition rate of crop residue in barley and canola canopies were the same. However, the initial nitrogen content of the straw type had a large effect on decomposition rate. Those crop residues with high N content decomposed the fastest.
The effect of residue decomposition rate and tillage were simulated in a conventional and zero tillage rotation of canola - pea - flax - barley to provide estimates of the annual changes that would be expected from such a rotation over a period of years.