THE IRRIGATION AGE. 



45 



fall off, and a discovery by the Department of Agri- 

 culture proved that a wilt or fungus disease was 

 responsible for the depreciation of the crop. Those 

 people have gotten all their lands infested with this 

 disease. They also have scab disease thoroughly 

 distributed on these lands, and their work, now, is 

 to get those lands back to their former condition by 

 some rotation or other treatment. 



"A new district in Southern Nevada which has 

 only been opened for agriculture a few years, has 

 been infested with a serious disease. They have 

 brought in potatoes from other districts without any 

 particular attention being paid to disease infection. 

 The result is their lands have been infested with 

 eel worms, a minute worm which causes knots on 

 the roots of the plants and causes rough potatoes. 

 When you get the eel worm into irrigated lands, it 

 is extremely difficult to get it out. 



"What have we to face here? There are, af- 

 fecting potatoes in the United States, at least a. 

 dozen different diseases sufficiently serious to re- 

 quire the careful attention of one section or another. 

 Some of them will never occur here. The late blight, 

 or rust, of New York, Maine and Michigan, will 

 never occur in the Snake River Valley, because it 

 only thrives in a humid climate. There are three 

 diseases, however, of sufficient importance to bring 

 before you, which we found in your fields today. 



''The most common trouble, here, in the irri- 

 gated districts, is sun blight. This disease causes 

 brown spots on the roots, especially on the part of 

 the stem just below the surface, and also a forma- 

 tion on the stem just below the surface, and also a 

 formation on the stem of aerial tubers. This, how- 

 ever, does not always produce this effect. It fre- 

 quently takes the underground root, in which case, 

 quite often, the potatoes are cut off and fail to grow. 

 This you will find very common in your fields here. 



"The second form you will see on a great many 

 of your potatoes, small black patches which stick 

 very closely to the skin, but may be rubbed off with 

 the finger nail. 



"The third form you will find in the nature of 

 a white covering on the green stem which is below 

 the soil surrounding the plant. This disease, so 

 far as we know, may be due to the character of 

 soil, to the water supplied, and to other factors 

 which are not fully known to us, but it can be con- 

 trolled by the manner of irrigation, so you will have 

 at all times not too much water applied, but keep 

 the soil open to the admission of air, and atten- 

 tion paid to the building up of the humus side of the 

 soil. This disease will be much more serious than 

 any other disease you will have here. 



"All districts suffer more or less with scab. This 

 disease, in the East, is controlled by attention to two 

 factors: First, that the seed shall be treated in 

 formaldehyde to destroy infection before planting. 

 Do not plant potatoes without treating them. Re- 

 member, also, that the disease is also carried in 

 manure, and I think it very questionable whether to 

 apply fresh manure on a potato crop. 



"The disease, for example, found in Greeley, 

 Colorado, I am confident, in the end, will be con- 

 trolled, not by any expensive treatment, but by the 



method of seed selection. A great deal of attention 

 should be paid to the introduction, right here, of 

 new varieties of potatoes thoroughly adapted to 

 your local conditions. 1 believe, when you have 

 done potato breeding here and have such varieties 

 that the tendency towards diseases, which are found 

 in most of the western districts, will largely disap- 

 pear. I believe that by breeding and seed selection 

 you can keep your diseases under control, with the 

 exception of wilt and scab, which are largely due to 

 fungus infection." 



Dr. Corbett's remarks were confined to seed 

 selection and to the importance of every potato 

 grower starting to grow his own seed, selecting the 

 best seed according to the ideal type being pro- 

 duced. 



Mr. Eugene Grubb was then called upon to 

 speak, and his remarks were, in part, as follows : 

 "Just a few points of observation today that will be 

 well for you to consider: All over Europe the first 

 essential for growing potatoes is drainage, and 

 deep trenching on the North Side Tract is good 

 drainage. We have found in Colorado that potatoes 

 deeply trenched and highly ridged ; potatoes grown 

 in cool, porous soil, were free from disease, because 

 all of the low, flat hills, which were excessively irri- 

 gated and caused the soil to be waterlogged, is 

 where the rough potatoes were found. Deep tillage, 

 deep trenching, frequent, but light waterings and 

 short irrigation rows are producing the best results 

 in Colorado. 



"Among other things, get your potatoes started 

 strong and vigorous, and that means large seed 

 pieces. Talking whole seed to people without ex- 

 perience is dangerous, but all over Europe, abso- 

 lutely without exception, I found no successful po- 

 tato grower but what used whole seed. 



"I wish we could demonstrate more fully to you 

 the need of less water. The potatoes that have been 

 going to Chicago and Pittsburgh from this section 

 have excelled in price the potatoes grown from any 

 other section on account of the quality, but if you 

 continue this profuse irrigation, you will soon lower 

 the quality of your potatoes and bar you from reach- 

 ing the markets at any distance from you. The 

 tuber does not take up any moisture. All that is 

 necessary is to furnish water to the feeder roots. 



"Many fields we have been in today we found 

 potatoes which were sunburned because they were 

 not covered up sufficiently. When you trench deep 

 you throw the soil on top of the hill. It covers the 

 tubers and keeps them from being sunburned. 



"In Wisconsin, Minnesota and Dakota I find 

 no farm storage. The potatoes that should be 

 marketed during six to eight months are thrown on 

 the market in a short space of time. The markets 

 have not storage facilities and you break and panic 

 the market. With storage on the farm, shipments 

 can be made from September until the middle of 

 June, and you will not always be at the mercy of 

 the potato broker. There should be some method 

 made here for the storage on the farm where you 

 can sort and grade your potatoes in the cellar in 

 the winter months, and not at the busy time, and 

 I think it not impossible that much of your troubles 



