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 trees for highway planting with excellent results. A careful investigation shows, however, that many of these seedling trees are maturing crops ranging up to eight hundred pounds. Quite a number have been reported yielding three hundred and fifty to six hundred pounds.

"I have experimental plantings aggregating about seven acres, some of which are four years old, budded and beginning to bear. My experience in bringing them on is what makes me interested in the proposed economic unit."

A particular tract of land that was yielding less than one-half ton of barley to the acre on the California continuous-soil-rubber-gully-washing system has been planted with carob. These pioneer planters are figuring on three tons to the acre. In the absence of all acreage data they would do well to divide this in two. In considering yields it should be remembered that the carob is a legume furnishing its own nitrogen, and nitrogen shortage is one of the great troubles of California agriculture, as it is of most other agricultures.

The conservationist should note that since the carob tree lends itself admirably to the small reservoir system of water conservation described on page 262, we may expect two checks on erosion—one with its roots and one with its field reservoirs. This latter might be one of its greatest advantages to the state through increase of water supply (page 289).

A very important Yankee discovery in connection with the carob is a greatly improved system of transplanting the trees. The young carob, like most trees of arid lands, has a root several times as long as the top. Thus it survives drought. But transplanting becomes a problem in a climate of 100° F, in summer, where there is no rain from April until October or November, and then only twelve to twenty inches in a season of winter rain. Planting the little seeds in place is slow and difficult, and the rabbits eat the leaves of seedlings if