Biodiversity is being encouraged by the adoption of conservation tillage practices, especially no-till farming. Spraying with a non-selective herbicide like paraquat means that weeds can be controlled without the need to plow.
Birds, in particular, are benefiting when fields are not plowed or only lightly cultivated in conservation tillage systems. Leaving stubble and chaff from the previous crop on the soil surface, and undisturbed no-till soil, provides habitats for invertebrates and small wildlife. Whether bird species feed on spilled grain and weed seeds, insects or small mammals, greater numbers are often evident.
One bird species now thriving in no-till fields in the intensive soybean growing areas to the north and south of Sao Paulo in Brazil is the burrowing owl (Athene cunicularia).
Found throughout much of North and South America, as their name implies, burrowing owls nest and roost in holes in the ground, perhaps dug by prairie dogs, for instance. During a recent ecological survey of fields in rural areas around the cities of Londrina and Uberlandia, burrowing owls and their homes were seen in many over-wintered no-till fields.
Originally a native of prairie grasslands, cultivation has meant that the birds have had to adapt to living within cropping systems. Plowing obviously destroys burrows, so in conventionally tilled fields the owls’ habitat is confined to the field margins. This may be a major reason for contraction in their range. No-till, however, means that the owls can thrive throughout fields.
Elsewhere in the world birds are taking advantage of conservation tillage practices. In Douglas County, Illinois, USA, golden plovers stop to rest and feed during their long migration from the Argentine pampas to their summer home on the shores of the Arctic Ocean.1 Ornithologists from the University of Illinois have noticed that the thousands of plovers which arrive over a few weeks in April and May seem to fit in well with the intensive corn and soybean farming in the area. In particular, birds seem to benefit from the no-till corn stubble waiting to be sown with the next crop.
1. No-till farmer.com. No-Till Fields Home For Migrating Birds