I was going to say I grew sugar beets for yeast culture and ethanol production as well as canola for lubricants and green diesel. Every climate has something you can grow for fuel and machinery lubricant. Yeilds will obviously vary depending on experience, land, climate, etc. some good resources are JTF Biofuel Library and Energy.gov

It’s also worth noting Syngas production in some sort of gasifier with almost anything is a super easy way to produce fuel too.