In the Great Central Valley irrigated alfalfa is the chief source of surplus, but there are many other honey plants which yield a large amount of nectar. In the southwestern counties of Santa Barbara, Ventura, Los Angeles, and San Diego, and in the western portions of San Bernardino and Riverside counties, beekeeping reaches its highest development in California. The principal honey plants are the orange, mountain sages, Lima bean, and wild buckwheat. In 1900, the Imperial Valley was a hot sandy desert, but twenty years later there were nearly 200,000 acres of irrigated alfalfa and cotton in this valley a hundred feet below sea level. The honey flow is very reliable and there are few unoccupied bee ranges.

During the past 20 years the number of colonies of bees on farms has rapidly grown smaller, largely as the result of brood diseases. There are many localities in which practically all of the small yards have been destroyed. Commercial beekeepers have welcomed the disappearance of the farmer beekeeper and bought up many small yards. The farmer beekeeper almost uniformly neglects his bees, and his few colonies become centers for widely spreading American and European foul brood. Their destruction has been a great benefit to the honey producer; but it has been the cause of an almost incalculable loss to agriculture. For the proper pollination of fruits of all kinds, of many vegetables, flowers, buckwheat, and many fodder plants, there ought to be at least a few colonies of bees on every farm. A few large apiaries can not and do not perform the work of pollination equally well. For example, during the period of fruit bloom there is often much rainy and cloudy weather; and unless there are colonies of bees actually in the orchards much of the bloom will not be pollinated. Reese has estimated that in West Virginia alone the loss from this cause amounts to a million dollars annually. The dependence of the farmer and fruit-grower on a large number of small apiaries is very generally recognized; and it is very desirable that there should be an increase in the number of colonies of bees on farms under a system of inspection which shall assure that they receive proper care.

The natural or physical units into which the United States and the several states have been divided in Part IV are based largely on an article entitled “Physiographic Divisions of the United States,” by Nevin M. Fenneman, Annals of Association of American Geographers, Vol. VI, pp. 19-98, 1917. Following the request of members of the United States Geological Survey, the Bureau of Forestry, the division of Pomology, and many geographers, the Association of American Geographers appointed a committee to devise a systematic division of the United States This committee consisted of five eminent geographers and geologists, who were assisted by a number of geologists selected because of special familiarity with various parts of the United States. The results of this committee’s work are incorporated in the article mentioned above. There is little reason to doubt that the divisions here given will continue in the main to be recognized as valid. The boundaries of most of the regions coincide with geological lines; and the regions differ to a great extent, as has already been pointed out, in elevation, topography, vegetation, and geological history.

While the United States census figures for 1900, 1910, and 1920, relating to bees and honey, have been carefully considered in the preparation of the following descriptions of the different states, they have been quoted only occasionally. The census reports on beekeeping are restricted to farms of three acres or more, producing $250 worth of agricultural products. But a great number of commercial beekeepers and many small honey producers live in cities and towns and own comparatively little land. It is estimated that, in the eastern portions of Massachusetts, New York, and Pennsylvania, where there are many large cities, not more than one-third of the beekeepers are included in the census figures. In California, again, which has doubtless a larger number of beekeepers and produces a greater