Net returns per acre are shrinking for many almond growers in the northern San Joaquin Valley.

"We're still seeing land prices going up and all other expenses going up."

Karen Klonsky is an agricultural economist at UC Davis. She says some of those other rising expenses include labor, irrigation, fertilizer…and bees.

"Almonds certainly are dependent on renting of hives and of course the cost of hives has gone up dramatically over the years as beekeepers are having trouble maintaining the health of their hives."

Almond growers typically spend about $280 an acre to rent bee hives which represents 10% of their production cost.

Federal statistics show that the addition of new almond acreage is beginning to slowdown in California. About 13,000 new acres were planted last year - the smallest amount in nearly 20 years.