Cashew are more labor intensive, grow in tropical climates.A tree of 40-50' yields only about 10lbs.
"Cashew nut processing
Extracting cashew nuts from their tough outer shells is a laborious and dangerous job - the outer shell contains a burning 'milk'.
The traditional way of extracting them has been by cracking them by hand, with a hammer and punch, wearing protective gloves.
ITDG has recently been working with local manufacturers to develop a machine that can shell the nuts without damaging them."
Faqs
http://www.originalnuthouse.com/facts/cashewfacts.
htm