486 REPORT OF THE COMMISSIONER OF AGRICULTURE. 
become visible on the surface during the dry season, as a white crust or 
efflorescence. They are of course found chiefly in low, level regions, 
such as the Great Valley, and the plains to seaward of the Coast Range; 
sometimes in continuous tracts of many thousands of acres, sometimes 
in spots so interspersed with non-alkaline land as to render it impossible 
to till one kind without the other. The nature and amount of salts in 
these soils is of course very variable. Near the coast the “alkali” is 
often little more than common salt, and can be relieved only by drainage 
or appropriate culture. At times we find chiefly magnesian salts, when 
liming will relieve the trouble. But in the Great Valley the name 
“alkali” is in most cases justified by the nature of the salt, which almost 
always contains more or less carbonate of soda, and sometimes potassa. 
The presence of these substances, even to the extent of afourth of one per 
cent., while it may do but little harm during the wet season, results in 
their accumulation at the surface whenever the rains cease, and the cor- 
rosion of the root-crown, stunting, and final death of the plants. But 
when stronger, as is too often the case, the seed is killed during germi- 
nation. Moreover, land so afflicted cannot be brought to good tilth by 
even the most thorough tillage. Fortunately, avery effectual and cheap 
neutralizer of this, the true “ alkali,” is available in the form of gypsum, 
which transforms the caustic carbonatesinto innocent sulphates. Wher- 
ever the amount of alkali present is not excessive, the use of gypsum 
relieves all difficulties arising from the presence of the former. More: 
over, analysis shows that in many cases large amounts of important 
mineral plant-food, such as potash, phosphates, and nitrates, accompany 
the injurious substances; so that when the latter are neutralized, the 
previously useless soil may be expected to possess extraordinary and last- 
ing fertility. Abundant deposits of gypsum have been shown to exist 
in many portions of the State since attention has been directed to its 
importance in this connection. 
On the eastern affluents of the Sacramento River, the American, Bear, 
Yuba, Feather, and other streams heading in the region where hydraulic 
mining is practiced, a new kind of soil is now being formed out of the 
materials carried down from the gold-bearing gravels. The enormous 
masses of detritus washed into the streams, filling their upper valleys to 
the height of 60 feet and more with bowlders and gravel, while a muddy 
flood of the finer materials overruns the valley lands in their lower 
course, have given rise to a great deal of complaint on the part of 
farmers; and the “mining débris question” has been the subject of 
numerous lawsuits, and of much angry debate in the legislative halls. 
In some cases the lands so overrun are definitively rvined ; in others the 
new soil formed is of fair quality in itself, butas yet unthrifty; in many, 
the best quality of black adobe is covered many feet deep with an un- 
productive “slum.” By the same agency, the beds of the Sacramento 
and its tributaries have become filled to such an extent as to greatly 
obstruct navigation and to cause much more frequent overflows, whose 
deposit, however, appears to improve, in general, the heavy lands of the 
plain, as well as the tules. It is difficult to foresee a solution of this 
question that would be satisfactory to all parties concerned; the more 
as the navigation of the bay itself is beginning to suffer from the accu- 
mulation of deposit, the reddish sediment-bearing waters of the Sacra- 
mento being always distinguishable in front of the city from the blue 
water brought in by the tides. 
NATURAL PASTURES. 
The most obvious agricultural consequence of the climatic features pre- 
viously outlined is that meadows and permanent grass pastures, and: 
