September 1 is the farm lease deadline
Iowa Code § 562.6 says a farm tenancy continues beyond its agreed term into the following crop year, on the same terms, unless written notice of termination is served in the manner set by § 562.7 — and then the tenancy ends March 1 following. Section 562.7 gives three methods, each keyed to the same date: delivery with signed acceptance on or before September 1, personal service or publication on or before September 1, or certified mail deposited before September 1. Miss it and you have leased the ground for another year. The statute excepts a mere cropper and a tenancy under forty acres where an animal feeding operation is the primary use.