TALKS WITH PRACTICAL IRRIGATORS. 



POTATOES BY IRRIGATION. 



BY J. W. GREGORY. 



PROBABLY no other crop grown under irriga- 

 tion is of more importance, all things consid- 

 ered, than the Irish potato. It enters largely, 

 invariably and in a multitude of forms into all bills 

 of fare, whether upon the home table, at the hotel or 

 restaurant. The portability and keeping qualities of 

 the crop render it available the year round and make 

 it possible to ship the tubers to the antipodes to find a 

 demand and a paying market. Hence any region of 

 country that is sure to produce a fair crop of Irish 

 potatoes of good quality, may very properly be con- 

 sidered a good and safe farming country. 



Few, if any, of the crops grown by irrigation have 

 led the producer a livelier pace to find out what to 

 do and how to do it, to make sure of a good yield and 

 a sound, merchantable product. There has been 

 constant inquiry as to precise methods to be followed 

 in growing potatoes by irrigation, and " established '' 

 rules and methods have been subject to constant dis- 

 establishment and change. Gradually some things 

 have been found out, with reasonable certainty, 

 about growing potatoes by irrigation, and the follow- 

 ing paper upon the subject by a contributor to the 

 Greeley, Colo., Tribune, will be found of interest and 

 value. At Greeley potato-growing is the chief in- 

 dustry and a great success, and the potatoes are of 

 the finest quality. The writer in question says : 

 There was a time when the opinion generally pre- 

 vailed among the Greeley farmers that very little 

 water was needed in successful potato culture; no 

 such idea prevails to any extent now. The original 

 belief, or impression, arose from two sources. Old 

 settlers who had grown potatoes on the alluvial mar- 

 gins of the rivers before upland irrigation was prac- 

 ticed to any extent in Colorado, had been in the 

 habit of selecting choice places for this crop, where 

 the undersoil was always damp and little artificial 

 irrigation was required; they told us potatoes needed 

 very little water. Next, in a majority of our upland 

 soils, in the raw, unmatured state, it was found that 

 either early irrigation for potatoes or corn, or even 

 later irrigation in excess, resulted in the first in- 

 stance almost invariably in stunting the growth of 

 the vine, which turned yellow and sickly after the 

 application of the water; and in the second instance 

 often checked instead of stimulated the growth of the 

 tuber, and resulted in ill-formed potatoes and a small 

 yield. Now we have ascertained that all this is the 

 result of a condition of the soil; a cold mineral soil 

 almost destitute of. decayed vegetable matter, and 

 having little soluble material in it for plant food, 

 soddens down like a mass of plaster when water is 

 applied, and plants, especially corn and potatoes, 

 cannot assimilate much water to advantage when 

 planted in such land. Constant stirring of the soil 

 of course benefits the crop under such circumstances, 

 but with a lean soil, whether of a sandy or clayey na- 



ture, no one could tell before we resorted to heavy 

 manuring of our lands, whether a very early irriga- 

 tion rendered necessary from the absence of the 

 usual spring rains, would benefit or injure the potato- 

 crop. Experience and practice are entirely different 

 now. As we began to apply manure in quantities to- 

 our lands in order, primarily, to increase their fer- 

 tility and the resulting yield, we made the discovery: 

 first, that the plants needed more water or the ma- 

 nure would burn them ; and next, that with richer soil 

 and more plant food, rendered soluble and available 

 with water and cultivation, both potatoes and corn 

 could stand more water and earlier in the season, not 

 only without injury but with material and perceptible 

 benefit. 



MORE WATER USED. 



So now we use twice the water we used to think 

 either safe or necessary. At one time in the history 

 of potato farming near Greeley, we, all of us, figured 

 that if it became necessary to irrigate potatoes to 

 bring them up, the chances were just about even be- 

 tween total failure if we did not put on the water and 

 a practically total failure if we did. Now, the mo- 

 ment we get done planting, if the ground is too dry 

 to bring the potatoes up, and if the prospect of co- 

 pious rainfall is not extremely favorable, no one fears 

 and very few hesitate to furrow out the ground and 

 put on the water at once; and if the seed is in fair 

 condition it is the uniform experience that the young 

 plants will push themselves through the earth in an 

 astonishingly short time, and grow with vigor after 

 they come up. 



We used to believe that two irrigations were suffi- 

 cient under ordinary circumstances, as to rainfall, to 

 mature an average crop of potatoes. Three irriga- 

 tions under the conditions of extreme drouth were 

 considered ample; now we know better and we have 

 not learned what we know about the matter from 

 agricultural reports or treatises on irrigation from a 

 scientific standpoint by civil engineers. All these 

 sources of information have combined to instruct 

 us in the pleasant but fictitious theory that as the 

 country got older and the desert became subdued to 

 cultivation, less water would be required; whereas the 

 facts are that as the country gets older and improved 

 methods of cultivation supersede the first primitive 

 efforts; as the soil is enriched by liberal coatings of 

 manure, or by the turning under of masses of alfalfa, 

 rich nitrogen and other plant foods, more and more 

 water is required to produce the best results. We 

 irrigate our potatoes from four to eight times now 

 and we know from experience, and not from theory, 

 that if we could run the water down our potato rows 

 once every week from the time it first became neces- 

 sary or advisable to apply the water, until the growth 

 of both tuber and vine was completed, the results 

 would be all the better; only provided that the soil is 

 well drained and thoroughly enriched with manure 

 or alfalfa and that cultivation is thorough. 



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