Furthermore, the Germans showed a long-term tendency to keep the farm in the family and to avoid having their children move to towns. For example, they generally preferred oxen to horses for plowing. The Scots Irish built their livelihoods on some farming but more herding (of hogs and cattle). In the American colonies, the Scots-Irish focused on mixed farming. Using this technique, they grew corn for human consumption and for livestock feed, especially for hogs. Many improvement-minded farmers of different backgrounds began using new agricultural practices to increase their output. During the 1750s, these agricultural innovators replaced the hand sickles and scythes used to harvest hay, wheat, and barley with the cradle scythe, a tool with wooden fingers that arranged the stalks of grain for easy collection. This tool was able to triple the amount of work done by a farmer in one day. A few scientifically informed farmers (mostly wealthy planters like George Washington) began fertilizing their fields with dung and lime and rotating their crops to keep the soil fertile.