Dad gum farmers plant high corn right up to our runways at four of the local R/C fields.
So I use the Walston Retrieval Systems set up which includes a mini transmitter in your plane and a direction finder receiver that i keep in the truck.
This garantees that i will never have my plane land out in the corn. I've had the Walston for 3 yrs and have not had a reason to go into the corn jungle.
http://www.walstonretrieval.com/main.htm