or twenty-eight bushels to the acre; or, if he will give it extra care in plowing and planting, he may increase that return to forty, fifty, sixty, or even seventy bushels to the acre. His oats will yield from forty to eighty bushels; barley, thirty to sixty; potatoes from one hundred to three hundred, and cabbage ten to twenty tons to the acre. The largest crops mentioned have been exceeded-some of them 100 per cent."

We have seen that Horace Greeley took this all in, and on his return to New York, wrote in The Tribune that if all the lands of Union Colony should be plowed the coming winter, he believed that they would yield an average of forty bushels to the acre. Now how much of the above have we found to be fact and how much fiction?

I think that farmers at large in the colony will agree with me when I say, that the average of wheat on new breaking has not exceeded fifteen bushels, and on old ground twenty bushels for the twenty years we have been cropping; that the average of oats on upland, not manured, has not been over thirty bushels, and that of barley, twenty bushels. The year just past has given, in my opinion, the largest average of any year since the colony settled here, and may be close to thirty bushels. But for the two years before, the average was below fifteen bushels.

That our grain crop of last year was the largest we have raised, would seem to prove the opinion advanced when we came here, that "irrigated land never wears out." But this is not really the case. The water supply being so deficient in 1887-1888, the soil did not yield nearly its average crop, and there was a stored-up fertility which became available when we had a year of seasonable rains and plenty of water for irrigation, during the small grain season. It was in a manner, and in some places completely so, a summer fallowing of the land. Our experience is that continual cropping, without returning anything to the soil, gradually exhausts it, and especially, if grain crop follows grain crop. This practice has long been abandoned on the lands of Union Colony. The rotation has been wheat and potatoes, where the latter do well. It was found that much larger crops of wheat could be grown after potatoes than after corn. The latter crop is used in rotation, where potatoes do not do well. This land is usually heavier than that adapted to the potato, and hence does not show signs of exhaustion so soon as if the same rotation were followed on the lighter soils. But following up any of these rotations for a number of years, and the observing farmer can see a diminution of yield. From the nature of things, this must be so, if the water of irrigation does not contain a sufficient amount of the important elements, needed

by agricultural crops, to restore year by year what is removed by these crops. If we keep drawing constantly from our bank account, without making fresh deposits, its depletion must come sooner or later, however large it was on the start. To be sure, there are certain elements in the soil needed by crops that are practically inexhaustible, while others are supplied by water and air in unlimited abundance. In nearly all cases the question is narrowed down to this, "Is there enough phosphoric acid, potash and nitrogen in the soil to supply the yearly drain of these substances?' These are in quite limited quantities in all soils, but vary in their relative proportions. Perhaps the most important of them-phosphoric acid-may be present in large quantities, but in a state that renders it slowly soluble, and hence may keep up the needed supply for centuries. Plenty of water would increase the quantity dissolved, and would increase the yearly supply for the successive crops. But, if this or the other elements are in a state easily soluble, a large application of water will carry them off in the under-drainage. Hence, it is found that, in some countries, irrigation only enables a soil to exhaust itself more rapidly. Porous soils, with gravelly subsoils, needing two or three times the quantity of water that soils with compact clay subsoils need, it will be seen, must soon exhaust themselves if the waters of irrigation do not contain the three indispensable constituents above named. The lands of Union Colony vary exceedingly in this respect. Take the soil of Lone Tree Valley, or that of Black Hollow, such is the nature of the subsoil that but very little of the water of irrigation can get through, and the body of the soil is so deep that for a long time it must remain practically inexhaustible, provided that it is not unusually deficient in one or more of the constituents referred to. Take, on the other hand, most of the land under Number Three, especially on the "delta,” and we have the other extreme. This is mostly new soil, deposited from a wash from the upper bench lands, which here deposited mostly gravel and sand, its finer particles being carried off into and down the Poudre. Close beneath, in most cases, is coarse gravel. The duty of water on such land is not more than one-third of that on the lands before mentioned. This is the character in general of all second bench land, such as that of the Big Bend of the Platte or that on the same stream below the Plumb bridge. On such land alfalfa needs three heavy irrigations for three cuttings, while on land with a deep, close subsoil, one irrigation will make three good, heavy cuttings. So, when we speak of the duty of water, it is important to know the character of the soil, as this may make it vary from one to three under the same management. Then, again, over the river, we have soils of

light, sandy loam, with compact clay subsoils from twenty to fifty feet deep, before reaching the gravel. These soils require but little water, and the irrigation of them cannot produce any rapid depletion of the elements of fertility. But, upon the immediate surface, these soils are not so plentiful in nitrogen, which is mostly found in humus. Hence, we find that oats and corn exhaust these soils, and upon them potatoes and wheat have been the principal crops. But, one year with another, it is found that the average is falling off, and farmers are hauling manure, in some cases, great distances, to restore the lost fertility. Others are keeping more stock on the farm, especially horses, for breeding purposes, to get a home supply of manure. The extensive production of alfalfa has enabled our farmers to do this, and is working a revolution in our methods of farming. Not only does it afford the means of making large quantities of manure, but it is found that, when turned under, it is even a better fertilizer than red clover. M. J. Hogarty, last season, had a large field turned over and planted to potatoes, one part being clover sod and the other alfalfa. He informs me that the yield on the alfalfa was two to one of that on the clover. J. Max. Clark had a piece of alfalfa turned over last spring also, and had it planted to potatoes, while he planted an adjacent piece heavily manured with stable manure, and the alfalfa sod surpassed the manured land two to one.

The reason that alfalfa increases the available fertility is this: Its roots penetrate the soil, when grown for a number of years, some fifteen feet deep, if the subsoil is favorable, as it is on the natural potato land we have spoken of. It draws on all this body of soil for the production of its immense top growth of stems and leaves. These latter fall in great abundance on the soil at each successive cutting, and are rotted on it by the succeeding irrigations. Then, again, there is a great quantity of thick roots, covered with bunches of spreading stubble, the remains of successive cuttings. That all this material is rich in nitrogen there can be no doubt. Alfalfa belongs to the leguminous family of plants, all of which, but the clovers in the most marked degree, have the property of appropriating large quantities of nitrogen from the air, if not directly through their leaves, which is doubtful, then through their roots. This is proved by the fact that soils poor in nitrogen will produce plants of this family better than any other; that these plants are themselves, both in stem, leaves and seeds, rich in nitrogen; and that when they have been grown for a succession of years on land poor in nitrogen, it becomes richer in this element. Hence, it is to be inferred, that the chief advantage to the soil derived from this plant is nitrogen. But, in addition to this, it no