We have abundant experience to show that forty or fifty colonies of bees, take the seasons as they average, are all that a single place will sustain to the greatest advantage. Then, how significant the fact, that when the season is the best, full three times that number of colonies will find ample resources to keep all employed. So this subject of artificial pasturage becomes one well worthy close study and observation. The subject, too, is a very important one in reference to the location of the apiary. It is well to remember in this connection, that two or three miles should be regarded as the limit of profitable gathering. That is, apiaries of from fifty to one hundred or more colonies, should not be nearer than four or five miles of each other. [Illustration: Fig. 74.-_Willow._] APRIL PLANTS. As we have already seen, the apiarist does not secure the best results, even in the early spring, except the bees are encouraged by the increase of their stores of pollen and honey; hence, in case we do not practice stimulative feeding--and many will not--it becomes very desirable to have some early bloom. Happily, in all sections of the United States our desires are not in vain. Early in spring there are many scattering wild flowers, as the blood-root (_Sanguinaria canadensis_), liver-leaf (_Hepatica acutiloba_), and various others of the crowfoot family, as also many species of cress, which belong to the mustard family, etc., all of which are valuable and important. The maples (Fig. 73), which are all valuable honey plants, also contribute to the early stores. Especially valuable are the silver maples (_Acer dasycarpum_), and the red or soft maples (_Acer rubrum_), as they bloom so very early, long before the leaves appear. The bees work on these, here in Michigan, the first week of April, and often in March. They are also magnificent shade trees, especially those that have the weeping habit. Their early bloom is very pleasing, their summer form and foliage beautiful, while their flaming tints in autumn are indescribable. The foreign maples, sycamore, _Acer pseudo-platanus_, and Norway, _Acer platanoides_, are also very beautiful. Whether superior to ours as honey plants, I am unable to say. The willows, too (Fig. 74), rival the maples in the early period of bloom. Some are very early, blossoming in March, while others, like the white willow (_Salix alba_) (Fig. 74), bloom in May. The flowers on one tree or bush of the willow are all pistillate, that is, have pistils, but no stamens, while on others they are all staminate, having no pistils. On the former, they can gather only honey, on the latter only pollen. That the willow furnishes both honey and pollen is attested by the fact that I saw both kinds of trees, the pistillate and the staminate, thronged with bees the past season. The willow, too, from its elegant form and silvery foliage, is one of our finest shade trees. [Illustration: Fig. 15.--_Judas Tree_]