He saw demand falling or what? What did he swap to?

He saw demand falling, exports falling due to the strong dollar and increased productivity in international farming, mismanagement at the canneries with executives cashing out using leveraged buyouts and saddling the companies with unsustainable debt, and trouble finding enough labor (peaches are harvested by hand, almost entirely by migrant workers from Mexico because no native Californian is willing to climb up and down ladders all day in 110 degree heat and 100% humidity, and it's hard to ensure legality).

He switched to almonds and walnuts, which are less labor intensive and have better management on the processing side. But they are an export-heavy market and have also been hammered by the strong dollar. Inflation-adjusted crop prices are near all time lows while costs are at all-time highs. Farming is a hard business!