They can be a real problem on farms, where they zero in on the abundance of food. Crows and ravens have a particular liking for grapes, soft fruits, potatoes, nuts and grains. They remove fruit directly from trees, land on trellises which collapse under their weight, and despite their size, can perch directly on stalks of grain, snapping off plants such as wheat and sorghum.
The larger ravens have a reputation for attacking lambs, although many believe they only go for sick animals or those abandoned by their mother. They are frequent visitors to roadsides, where they feast on the carnage of dead wildlife left behind by cars.
They are not always welcome backyard visitors as they have a habit of scaring away the smaller native birds. Planting an understory of spiky shrubs is a good way to give the smaller birds somewhere to hide when the big bully birds show up.