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
Cover crop ("Sinapis alba") and radish ("Raphanus sativus"). They can be grown after a main (cereal) crop and trap nematodes, for example the beet cyst nematode and Columbian root knot nematode. When grown, nematodes hatch and are attracted to the roots. After entering the roots they cannot reproduce in the root due to a hypersensitive resistance reaction of the plant. Hence the nematode population is greatly reduced, by 70-99%, depending on species and cultivation time. Other cover crops are used to attract natural predators of pests by providing elements of their habitat. This is a form of biological control known as habitat