IRRIGATION INVESTIGATIONS ON CACHK CREEK. 161 



iat-ly fittwl for the production of early fruits and vegetables. About one-half of the 

 area of thi^: valley is a stiff clay or adobe. This is more difficult to work, and under 

 irrigation requires drainage and the exercise of care and judgment in the use of water 

 to get the best results. At present, except at the upper end of the valley, where a 

 good deal of fruit is produced, most of the valley and the smoother hill slopes are 

 given over to wheat. The valie}- being narrow, water used for irrigation can not be 

 taken far from the stream, and a large part of the water diverted must return in the 

 form of seepage. This would be especially true of the water used in winter irriga- 

 tion, which would return gradually during the following summer. It is a conunon 

 experience in other localities that the use of water in the upper reaches of a valley 

 like the Ca^^ay results after a little time in an increase of the summer flow of the 

 stream below. It takes a little time to establish the new regime, but there is no 

 doubt that a liberal use of water in the winter and early spring in Capay Valley will 

 improve Cache Creek as an irrigating stream. 



Cache Creek in times of flood brings large quantities of sediment from the hills. 

 Since the country has been settled and the hills pastured the volume of such material 

 brought down is much increased. Some of it is deposited in the upper vallev. and 

 much of the best fruit and alfalfa land of this section is built up of this deposit, but 

 the larger part of this material is carried out into the lower valley, where, because of 

 the change of grade and consequent slower velocit}' of the stream, it is dropped. 

 The bed of the stream is gradually being filled up with this wash. The coarser 

 material is deposited where the grade first flattens, and the lighter sediment is carried 

 on below. The gravel beds in which the stream sinks near Capaj- are the accumula- 

 tions of the coarser material. During floods, when the river gets outside its banks, 

 the suspended material is dejKJsited on the submerged lands nearest the stream. The 

 creek has thus built up along its banks a ridge of this sedimentary matter. The 

 material transported when the stream does not escape from its banks and such as is 

 carried in the main current in the greater floods is deposited on the west side of the 

 great Saci-amento Slough. There is a strip of this material several miles wide 

 extending from above Blacks Station, in the northern part of Yolo County, to Putah 

 Creek, in the southern part, a distance of about 18 miles. The avei-age width of 

 this strip is about 6 miles. The location and extent of this deposit is shown on 

 the map (PI. XI, p. 156). There is no finer agricultural soil than this sedimentary 

 deposit. It is mellow, warm, and fertile, with good drainage, jet holding a reserve 

 of moisture to resist drought. It is ideal grain, alfalfa, and fruit land. You may 

 find growing on this soil wheat, barley, oats, corn, alfalfa, all the vegetables of a 

 tempei-ate and subti-opical climate, apples, apricots, nectarines, plums, pears, prunes, 

 oranges, lemons, limes, figs, pomegranates, grapes (table, wine, and raisin), olives, 

 almonds, English walnufs, berries of all kinds, and melons. Some of these lands 

 are better adapted to particular crops than others, jet I venture to say that there 

 are 80-acre ti-acts of this sedimentarj- soil in this valley on which everything that 

 has been named is now produced, and I am not sure but that within a single block 

 in the town of Woodland most of these fruits and vegetables can be found growing. 

 There is of this choice land in Yolo County approximately 50,000 acres in one body 

 which may fairh' be considered as Cache Creek's contribution to this deposit, and 



23856— No. 100—01^—11 



