Crop desiccation is used as a pre-harvest herbicide and harvest aid on cereal crops including wheat and oats and on oil seed rape. As a systemic herbicide it is not a true desiccant as it can take weeks rather than days for the crop to die back after application. In the UK, it began to be applied to wheat crops in the 1980s to control perennial weeds such as common couch which was very effective and meant that sowing of the next crop could occur sooner. Use as a harvest aid in the UK increased after the introduction of strobilurin fungicides which
Crop residue whereas cereal straw would reduce next year's soil supply of available nutrients. Over time, the nutrients fixed by soil microbes and humus are released and available to crops. Nutrients from residue are not fully recovered by crops. Just like fertilizer nutrients, nutrients released from crop residue into the soil are susceptible to losses such as leaching (N and S), denitrification (N), immobilization (N, P, K and S), and fixation (P and K). The efficiency of nutrient uptake by crops from fertilizers or residue release is generally thought to be similar. For example, about 50 percent recovery of N in the