The advantages of fall sowing are many. As stated, successful germination is favored by the presence of an abundance of fertility, especially of nitrates, in the soil. In summer-fallowed land nitrates are always found in abundance in the fall, ready to stimulate the seed into rapid germination and the young plants into vigorous growth. During the late fall and winter months the nitrates disappear, at least in part, anti from the point of view of fertility the spring is not so desirable as the fall for germination. More important, grain sown in the fall under favorable conditions will establish a good root system which is ready for use and in action in the early spring as soon as the temperature is right and long before the farmer can go out on the ground with his implements. As a result, the crop has the use of the early spring moisture, which under the conditions of spring sowing is evaporated into the air. Where the natural precipitation is light and the amount of water stored in the soil is not large, the gain resulting from the use of the early spring moisture. often decides the question in favor of fall sowing. The disadvantages of fall sowing are also many. The uncertainty of the fall rains must first be considered. In ordinary practice, seed sown in the fall does not germinate until a rain comes, unless indeed sowing is done immediately after a rain. The fall rains are uncertain as to quantity. In many cases they are so light that they suffice only to start germination and not to complete it and give the plants the proper start. Such incomplete germination frequently causes the total loss of the crop. Even if the stand of the fall crop is satisfactory, there is always the danger of winter-killing to be reckoned with. The real cause of winter-killing is not yet clearly understood, though it seems that repeated thawing and freezing, drying winter winds, accompanied by dry cold or protracted periods of intense cold, destroy the vitality of the seed and young root system. Continuous but moderate cold is not ordinarily very injurious. The liability to winter-killing is, therefore, very much greater wherever the winters are open than in places where the snow covers the ground the larger part of the winter. It is also to be kept in mind that some varieties are very resistant to winter-killing, while others require well-covered winters. Fall sowing is preferable wherever the bulk of the precipitation comes in winter and spring and where the winters are covered for some time with snow and the summers are dry. Under such conditions it is very important that the crop make use of the moisture stored in the soil in the early spring. Wherever the precipitation comes largely in late spring and summer, the arguments in favor of fall sowing are not so strong, and in such localities spring sowing is often more desirable than fall sowing. In the Great Plains district, therefore, spring sowing is usually recommended, though fall-sown crops nearly