Having been through the blood bath of the early 80's would like to make a few comments based on my personal experience.  

In addition to high interest rates one of the bigger issues causing the early 80's meltdown was the amount of short and intermediate term debt many farmers were carrying.  Back then the Production Credit Association (PCA) was the source of short and intermediate term money and the Federal Land Bank was the long term lender for real estate,  They were 2 separate entities operating under the Farm Credit System umbrella.  

In the late 70's the PCA was aggressively lending money with extremely lax lending regulations.  Lots of money was loaned on equipment along with pork and dairy start up and/or expansion.  When high interest rates hit the resulting impact on short and intermediate term loans created a cash flow crisis for farmers carrying significant debt.  One of the major things I, and many others, learned from this is keep a tight reign on this kind of debt.  When things tighten up, such as they are beginning to now, it is measy to get underwater on equipment loans when the value of the equipment is significantly less than the amount owed. Liquidation becomes a painful process if it is needed to improve cashflows.