184 AGRICULTURAL REPORT. 



flow. The surplus waters of the great river-floods also deluge these 

 tracts, keepiug thoiu .submerged during several mouths audmaintaiuing 

 a wet aud swampy couditiou duriug tlic remainder of the year. 



These overflowed areas arc called "tules," au ludiau word signifying 

 a coarse, reedy grass, which grows luxuriautly upon the wet soil, and 

 which is now used to designate the lands themselves. These tules 

 border the rivers aud their larger tributaries for a very large portion 

 of their respective courses. In the upper part of each valley their 

 edges are from half to three-quarters of a mile from the rivers,"but to- 

 ward their mouths this intervening space becomes narrower. The 

 banks decline iu height and the rivers cut numerous channels, called 

 sloughs, through the tules, forming a great number of islands of various 

 sizes, and separated mostly by navigable streams. This multiplication 

 of channels gives a greater sco])e for the periodical high waters than do 

 the narrower upper portions of the valleys, and hence the floods are 

 more easily controlled. This renders the process of reclamation in the 

 fresli-water tide-lands easier and less expensive than in the regions 

 above, where, as yet, but little has been done in that way. 



The characters of the two rivers, the Sacramento aud the San Joa- 

 quin, present some marked differences, which are illustrated by corre- 

 sponding differences iu the lands on their banks. The Sacramento is a 

 more violent stream. Its large txibutaries head high up among the 

 Sierras and bring large bodies of water from the melting snows, which, 

 are precipitated more suddenly than the floods of the San Joaquin. The 

 Sacramento has also a smaller number of channels through whicli to 

 discharge its surplus waters. To relieve this diificulty it has been pro- 

 posed to cut an artificial channel from Cache Slough, through, the Monte- 

 zuma Hills, to one of the streams farther west, emptying into Suisun 

 Bay. It has been estimated that this channel will be but seven miles 

 long, with a declivity ranging from 2 to 14 feet per mile. The tributa- 

 ries of the Sacramento have also been the theater of a more extensive 

 mining enterprise, the debris of which, discharged into the river, have 

 given a specific character to the sediment it deposits upon the lowlands. 



The islands of the Sacramento are generally basin-shaped, their inte- 

 rior parts being depressed below their edges. Their banks, like those 

 of the riparian tules higher up, are studded Avith willow, alder, sycarnore, 

 live-oak, and other large timber, interspersed with a copious under- 

 growth of shrubs and vines. The centers of these islands are covered 

 with tules of a very tall and luxuriant growth. The islands of the San 

 Joaquin do not exhibit so decided a tendency to this basin-like forma- 

 tion. Their edges are not so elevated, nor are they so covered with 

 vegetation, while iu their interior parts the tule is thinner and shorter. 

 "Willows here grow in bunches, and diff'erent kinds of coarse grass are 

 found successfully maintaining them selves against the aggressive tules. 

 The surface-soil of the Sacramento islands is, to a great extent, com- 

 posed of clay, or a late deposit of yellow sediment, with a substratum 

 of almost pure organic matter in au advanced stage of decomposition. 

 In the islands of the San Joaquin, this organic matter is seen almost 

 entirely uncovered by later deposits. 



The tules of the islands and banks of these two great rivers, though 

 exhibiting these very perceptible differences, present points of general 

 resemblance indicating a common origin. They first appear above the 

 Straits of Carquinez, w^hich connects San Pablo Bay with Suisun, and 

 assume a more marked character as the water becomes less and less 

 brackish. Above the mouth of the rivers the alluvial clay-soil of the 

 salt-marsh, impregnated with alkali, gives place to the fresh- water tule- 

 soil, composed of decayed roots and grasses and other organic matter 



