180 AGEICULTUEAL REPORT. 



tlic correspou deuce of this Department, a crop of 80 bushels per acre 

 required an expenditure of only 30 pounds of seed per acre. After har- 

 vesting the first crop of wheat the waste grain left upon the ground, on 

 being irrigated, brings forth a crop of wheat-hay in sixty or eighty days. 

 This system of cultivation is yet in its infancy. AVhat results may yet 

 spring from it must, of course, be matter of mere conjecture. Appa- 

 rently, however, it justilies its departure from the old methods by its 

 common-sense adaptation to circumstances, as well as by its wonderful 

 success. 



The mode of reclaiming swamp-lands is by throwing up levees to keep 

 out the tides and river-floods. Self-acting gates permit the escape of 

 the water in one direction, while they prevent its return. The earth 

 from which this embankment is constructed is taken from a ditch which 

 is generally dug inside of the dike. Small sloughs or creeks are dammed 

 in order to escape the expense of leveeing their banks. The drainage- 

 gates are placed at the mouths of these sloughs, and serve also for the 

 admission of water for irrigation during the growing season. This work 

 was at first done by Chinamen, but several ditching-machines have been 

 tried, some of them with substantial success. The cost of embankment 

 varied from 10 to 25 cents per cubic yard. 



The views of the parties who inaugurated the system of tule reclama- 

 tion were too limited to embrace the conditions of final success. It was 

 discovered that a dike that would be sufficient for the reclamation of 

 the salt-marshes upon the bay, where the rise occasioned by river-floods 

 is limited, would be wholly inadequate to resist the sudden and enor- 

 mous i^ressure of inundation in the river- valleys during the rainy season, 

 especially in those years in which the annual rain-fall reaches its period- 

 ical maximum. The climate of California exhibits a remarkably wide 

 range of hyetal conditions, which, as yet, are very imperfectly under- 

 stood. During the twenty-three years ending with 1871 the annual 

 rain-fall at San Francisco varied from 7.G0 inches, in 1850, to 49.27 inches, 

 in 18G1. The distribution of this rain-fall through the season is also 

 very irregular, sometimes producing the most devastating floods. A 

 system of reclamation works in such a region should be constructed with 

 reference to the extreme pressure that is likely to be brought against 

 them. The spring floods of 1872 were very destructive of these works, 

 overflowing lands supposed to be sufficiently i)rotected, and sweeping 

 away crops and improvements. In some cases, it is said, the embank- 

 ments were so unscientifically constructed as to force the waters upon 

 lands that had not previously been overflowed. Persons anxious to 

 secure as large an area as possible of new land encroached upon the 

 channels, and thus raised the water-level above what it would otherwise 

 have been. 



These untoward 'results indicated the necessit^f of a more liberal ex- 

 penditure and of more efficient construction. Large associations of 

 capitalists have entered the field, j^urchasing and reclaiming overflowed 

 lands in some cases for the purpose of selling them to individual culti- 

 vators, and in other cases to cultivate them themselves. It is stated in 

 our correspondence that the reclamation works constructed during 1872 

 were higher and stronger than those previously existing. At the close 

 of the year 1872, about 70,000 acres of fresh- water tide-lands had been 

 inclosed by levees, an<l furnished with self pxting tide-gates. Some of 

 these works were constructed upon the later models; others were en- 

 larged and brought to a state of efficiency that was esteemed ample to 

 resist extraordinary floods. The cost of these levees varied from $5 to 

 $15 j)er acre, according to the height and strength of the embankment, 



