Following World War II more trees began to be planted in plantations. Other changes were taking place as well, in the late 1940s and early 1950s farmers began to shear trees in response to customer demand for denser trees. During the 1960s the market for Christmas trees in the United States began to change. The number of part-time growers declined, while some part-time growers ceased operations others expanded their operations and became full-time Christmas tree farmers. Expansion occurred in all major U.S. Christmas tree growing regions, Michigan, the Pacific Northwest and North Carolina.