REPORT ON THE KLAMATH MARSH EXPERIMENT. 5 



iiiir the sumnior months, with the liabilitv of a killinu- frost even in 

 siimnier. Preliminary examinations of the drained niarshhmd 

 >hoAved the jiresence of consideral)le quantities of alkaline salts, chiefly 

 carbonates of sodium, magnesium, and calcium. It was believed at 

 first that these salts could be washed out without difficulty in the 

 ordinary processes of irrigation, and the first efl'orts were directed 

 toward getting the raw tule mat into good tilth. Arrangements 

 were nuule for liringing to the reclaimed land a supply of irrigation 

 water from the channel which leads into the swamp from the Klamath 

 River. 



The drainage of the experimental tract had been accomiDlished by 

 cutting through it open ditches about 5 feet deep and 2 feet wide. 

 Three of these ditches were run parallel, about 200 feet apart, con- 

 necting with a head ditch at either end and supplemented by a 

 dredger cut along one side of the tract. This arrangement of ditches, 

 together with a wooden flume by which the irrigation water was 

 brought to the tract, made it possible to try both surface flooding 

 and lateral subirrigation, the latter being accomplished by keeping 

 one ditch full of irrigation water and the adjacent parallel ditch 

 empty. 



It was found that the raw tule mat was very tough and hard to 

 reduce quickly into good tilth. It was successfully plowed by using 

 a very sharp plow. In order to have at least a small piece of land in 

 good tilth, the furrow slice was removed from about 1 acre. After 

 this was done it was found possible to work up the next layer into 

 verv good tilth for a seed bed. 



In the spring of 1910, when the irrigation system had been in- 

 stalled, a number of grain and grass crops, together with a series of 

 vegetable crops, were planted ; a considerable number of the crops 

 being planted both on the land from which the furrow slice had been 

 removed and on the land that had not been plowed the previous sea- 

 son, but instead had been thoroughly cut to pieces with a heavy disk. 

 It was found impracticable to plant crops on the land which had been 

 plowed but from which the furrow slice had not been removed. 

 "When this plowed land had been cut to pieces with the disk and 

 irrigation water was applied in an endeavor to moisten the seed l^ed, 

 most of the pulverized furrow slice Avas floated up and washed about 

 by the irrigation stream, so as to make a uniform wetting impossible. 

 Spring planting on this land was not attempted. 



AMien the drainage of the experimental tract was first undertaken 

 a large number of curbed open wells were dug for the purpose of 

 observing the rate of recession of the ground water. 



"With the beginning of the crop season of 1910 observations were 

 l>egun as to the depth of the water in these open wells, and samples of 

 the water were tested from time to time with the electrolytic bridge 



[Cir. 86] 



