Prunes were shaken from trees rather than picked by hand, then gathered from the ground, hauled to a shed, dipped in boiling water and lye to crack the skin and keep the fruit from swelling, and spread on trays to dry in the sun for a week. In the fall of 1918, an unexpected three-day rainfall caught the county's entire prune crop lying on trays, and the odor of fermenting prunes lingered long after the ruined crop was collected and destroyed. Prunes were eventually dried in dehydrators and graded by size and quality. Sunsweet, a cooperative of prune and apricot growers, developed the tenderized prune by boiling it to make it softer and more palatable, and in the 1960s introduced the pitted prune after an employee invented a mechanized prune pitter. Shortly after World War II, Paul Mariani, Jr. introduced the first commercially sold soft unfallen prunes in transparent packages; although competitors initially scoffed, within five years the transparent moist-pack became the dried-fruit industry's packaging standard. Picking prunes from the ground was hard on the knees and frustrating because after a week spent gathering thousands of fallen prunes, more unfallen prunes had dropped and the work had to begin again.