Fires swept over the prairies any time during practically ten month a year, although the worst were usually in the fall, with the grass standing high and rich in oily seeds. The prairie fires could be set by lightning, by the carelessness of greenhorns in the country, by sparks from the railroads, and the deliberate malice. Once started, the heat of the fire created a high wind that could sweep it over a hundred miles of prairie in an incredibly short time. Settlers soon learned to watch the horizon for the curling smoke rising from prairie grass. At the first sign of this, everyone hurried to the flames with water barrels, gunnysacks, hoes and particularly ploughs to dig furrows so as to prevent the fire from spreading. Even more important was the awareness of the danger ahead of time, early enough so fireguards were ploughed around the homestead, at least around the buildings.