ceras). The poplars yield large quantities of pollen, which is eagerly gathered by bees.
The more important nectar-yielding plants are as follows: Willow (Salix amygdaloides), box elder (Acer Negundo), Plum (Prunus americana), dandelion (Taraxicum officinale), apple (Pyrus Malus), mountain maple (Acer glabrum), rattle-weed or loco (Astragalus caryocarpus), wild gooseberry (Ribes irriguum), choke cherry (Prunus virginiana), figwort (Scrophularia marylandica), white clover (Tri-folium repens), alfalfa (Medicago sativa), yellow sweet clover (Melilotus officinalis), raspberry (Rubus deliciosa), salmon berry (Rubus parviflorus), black locust (Robinia Pseudo-Acacia), Red gaura (Gaura coccinea), purple gilia (Gilia pungens), honey locust (Gleditsia triacanthos), deer’s tongue (Frasera speciosa), Rocky Mountain Bee Plant (Cleome serrulata), sunflower (Helianthus annuus), white sweet clover (Melilotus alba), red mallow (Malvastrum coccineum), rabbit brush (Chrysothamnus pumilus), oreocarya (Oreocarya virgata), rosinweed (Grindelia squarrosa).
The wild bloom is of much value in building up the colonies in spring and should be familiar to every beekeeper. The Rocky Mountain bee plant is the source of only a small amount of surplus to-day, but in localities it is still important both in the eastern and western counties. In the foothills no shrub yields more nectar than the choke cherry. Rattleweed, raspberry, and mallow are freely visited by honeybees. White sweet clover is rapidly becoming more common, as it will thrive on land not adapted to growing alfalfa. It is believed that sweet clover will play an important part in the development of dry farming. There is a wealth of wild flowers in Colorado, many of which are to some extent visited by honeybees, but as a whole they are of little value to bee culture.
Total area, 122,634 square miles. The eastern part of the state belongs to the Great Plains; the north-central portion is occupied by the Rocky Mountains; and the western and southern portions are desert plains diversified by short mountain ranges with many intervening valleys, mesas, and lava beds. Of the 70,000,000 acres, approximately 2,000,000 acres are irrigable. Agriculture and beekeeping are mainly restricted to the valleys of the Rio Grande, Pecos, Canadian, and San Juan rivers and their tributaries. The soils in the river valleys are fertile sandy and heavy loams, which have been derived from the rocks of the neighboring hills. In the desert plains the soils are composed largely of gravel and sand. The higher mountain ranges and plateaus are forested with pine, fir, cedar, and oak. On the arid plains northward sagebrush and greasewood are abundant, and southward cactus and yucca. The only trees common along the rivers in the valleys are willows and cottonwood.
In 1920, 538,000 acres were under irrigation, and 66,000 acres were available for settlement. Irrigation is practiced mainly in four sections of the state. In the north-central portion, in the Rocky Mountain region, in the counties of Colfax, Mora, Taos, Rio Arriba and San Miguel, there are 206,000 acres irrigated from the Canadian and Rio Grande rivers and their tributaries. The annual rainfall in this section is from, 18 to 20 inches. In the southeast section, in Chaves and Eddy counties, 93,000 acres are irrigated from the Pecos River and its tributaries. In the Pecos Valley the annual rainfall is 15 inches. At times the river carries large floods, and at other times the water is mostly lost in the sands and by evaporation. In the south-central portion of the state in the Rio Grande Valley, in Dona Ana and Sierra Counties, there are 40,000 acres under irrigation. The average annual rainfall is less than six inches. On the high plateaus in the western part of New