On Sunday, Audrey Panitch Levin was at home in Philadelphia. On Wednesday, she was picking sweet potatoes in central Israel, part of an army of volunteers who have rushed to the nation's farms that are struggling with an acute labour shortage following Hamas' Oct. 7 cross-border attack. Israel's farms, most of which are in the centre and south of the country, traditionally rely on thousands of Thai and Palestinian workers to till the land and bring in the crops.