The key insight Silicon Valley lacks about agriculture is that there is little potential for a big win. Major improvements mean 10% of something, not 10x. US agriculture is already highly efficient. On the down side, there's potential for a big loss if you screw up.
This is actually the big insight big time agriculture lacks about agriculture. They are obsessed with volumes and consider their farms to be large spread out factories making commodities and the tons of commodities produced to be the only metric that matters. There are big wins to be had in making better food -- both healthier and better tasting. Most food in America tastes kind of bad and is very bad for you, so the…
You can turn almost any flat land into arable land given enough effort.
Terraced farming cannot be mechanised economically because you need very small combines that need to be transported up or down and building the terrace with excavators etc disrupts the soil which means you have to build it up which means hardly any productivity in the first decade. You got a huge equipment, logistics and construction problem which requires massive amounts of upfront capital for basically no cash flow during the most important years. We would need huge advances in agricultural robotics for this to be cost effective.