176 CALIFORNIA FRUITS I HOW TO GROW THEM 



which, theoretically, is dry, but which actually, with shallow furrows 

 over an irrigation hardpan, becomes too often saturated over nearly 

 the whole space between the trees. 



Cement Pipes and Flumes for the Furrow System. The use of 



cement in the construction of flumes, pipes and outlets for distribution 

 has advanced so rapidly during recent years that in nearly all districts 

 local cement works can be found, at which irrigation structures and 

 appliances of latest design can be studied. Other devices are first de- 

 scribed and afterwards regularly advertised in our horticultural jour- 

 nals. Analysis of them is beyond the scope of this treatise, but they 

 are none the less important and all who contemplate laying out irriga- 

 tion systems, both large and small, should consider them carefully. 

 It is the function of this work to deal chiefly with home-made appli- 

 ances. 



The Board Flume and the Furrow System. Although in the older 

 regions the cement flume is advancing in popularity, important service 

 will always be rendered by the home-made board flume where suitable 

 lumber is cheap. A detailed account of its construction and operation 

 will be widely useful. The following is contributed by Mr. A. S. 

 Bradford, of Orange county: 



I consider the board flume best because it is in many places cheapest and 

 because it will last fifteen or twenty years in California if made of good soft 

 redwood. The common redwood lumber is generally so, but the so-called flume 

 lumber is hard, generally, and will warp the flume out of shape. Even in the 

 common redwood lumber hard pieces will be found, and these should be avoided. 

 My first flume has been in use nine years and is apparently as good as ever. 



The first thing to be considered is getting a flume put in properly, as this 

 alone will cause much trouble if not done right. A flume should run nearly on 

 a level. It should be placed about two-thirds in the ground at the commence- 

 ment, and as soon as it comes out of the ground to about two-thirds of its 

 height, there should be a drop made of 1, 2, or 3 inches, if necessary, and then 

 carried along as before, so as to keep the entire length of flume practically on a 

 level. 



Sixteen-foot lumber is better than longer, as it is lighter to handle. I prefer 

 8-inch sides with 18-inch bottom, or, in some cases, 10-inch sides with 16-inch 

 bottom. The first section, however, should be about 2 feet wide, narrowed to the 

 size of the flume, so as to control the stream. Collars should be) put around the 

 flume everv 8 feet of distance; that is, one in the center and one to cover the 

 joints at each end. These collars should be 2 by 3 inch stuff on th bottom and 

 sides and 1 by three inches on top. This makes a strong, durable flume. The 

 length of the flume should be divided, so that the stream will decrease as it goes 

 along. The width should be decreased also, say from 16 inches to 14, 12, 10, and 

 8 inches, the sides being the same throughout or reduced so as to have 10-inch 

 sides on the 16-inch bottom and 8-inch sides on the rest, nailed to the side of the 

 bottom, making 7 inches depth inside. Two-inch holes should be about 30 inches 

 apart and 2-inch gates placed on the inside instead of outside, as they will col- 

 lect less trash, the hole through the wood, if uncovered, making a ''lodgment for 

 leaves, etc. In the narrow and flat flume it is much easier to fix the gates. 



From 8 to 9 furrows for trees set 24 feet apart is sufficient. The streams 

 should be run from one-eighth to one-half the capacity of the holes in the flume, 

 according to the soil and fall of ground. I commence the stream small and 

 increase it if necessary later on. The streams should be kept as near together 

 as possible, and when the end is reached the gate should be nearly closed down, 

 so as to allow the stream to just trickle to the end. In this manner the soil will 

 become thoroughly wet from one end to the other. The streams should be run 

 very slowly on most of our soils. A great many failures have been made on 



