1.- There wasn't sufficient workforce in the British countryside at the outbreak of WWII because every young men were leaving their works to join the armed forces, and the remaining young men were keaving to work in factories because there was a more profitable work. All of this caused a big need of workers.
2.- The first reaction of farmers to the WLA (Women's Land Army) was with suspicion and scorn. Because working in the countryside was considered not a place for a young woman.
4.- During this period of time many women lied of their age, to escape the city poverty, get a medical cursory, and work in the fields.