What is preferred in an emergency landing: a road or a cornfield?
Really depends on what you are flying, what's growing, what season and what the roads are like. Our Cessnas have used gravel roads a couple of times, either due to problems aloft or at the airport (bad weather). In the Alberta prairies finding a side road to land on is no problem whatsoever. 100 and 200-series Cessnas have fairly narrow fixed gear that can take an amazing amount of abuse, don't know about other types.

A real cornfield, with the corn fully grown, will destroy a light aircraft. The plants are 2-3m high with a hard, heavy log of corn at the top. Hit a couple of thousand of them at 100km/h..... (Skydiving centers in corn country have firm advice for landing in the corn: keep your legs crossed.)

Ripe canola is also nearly 2m high and is a bushy plant interwoven with it's neighbors. You'll probably flip over forward. Wheat is the best choice.