There is no sharp line of demarcation between market gardening and trucking or farm gardening. According to common usage trucking means the growing of vegetables on an extensive field scale. The operations may be near enough to market to transport the products by wagon, or removed hundreds of miles, in which case trains or boats are used in transportation. The land is seldom worth more than $300 an acre and usually much less. Such crops as cabbage, tomato, celery, sweet potato, sweet corn and other vegetables are grown and cultivated with horse implements. In some important trucking regions, as at Norfolk, Va., wheel hoe crops, including spinach and kale, are largely grown and shipped to market. Both market gardening and truck farming are often seen on the same farm. In some regions the farm gardening or trucking operations are restricted mainly to one or two crops; for example, the growing of late cabbage in western New York; tomatoes in Caroline county, Md.; celery and lettuce in Tioga county, Pa.; muskmelons at Rockyford, Col.; and sweet potatoes in certain sections of New Jersey.