CALIFORNIA FRUITS: HOW TO GROW THKM 



evaporation of moisture during our long, dry summer. For this 

 reason we can not use many plants which are used for green- 

 manuring in humid climates. Crimson clover, cow peas, etc., do 

 not make good winter growth unless the temperature is relatively 

 high and frosts few and light. They make exuberant growth for 

 a time in the spring when heat is adequate and moisture abundant, 

 but at that time it is too" late to grow crops for plowing under 

 because the soil is too dry for their decay and their presence tends 

 otherwise to the loss of moisture and makes it very difficult to 

 secure a good surface tilth. The greatest care must be had not 

 to alfow a growth either of cover crop or of weeds to stand too 

 long or its covering will do more harm than good. Hardy legumes 

 are therefore the desideratum both for winter forage and green- 

 manuring. The common "burr clover" (Medicago denticulatd) is 

 proving very satisfactory in some parts of the State, the "Canadian 

 field pea," the winter vetch, the hairy vetch and fenugreek are 

 coming into quite wide use in orchards in different parts of the 

 State. Which plant is best in any locality must be determined 

 by its local behavior. In some places native lupines make a good 

 natural cover crop. 



A Matter of Local Study. The recourse to cover crops in 

 the orchard or vineyard should be approached with a disposition 

 to careful study and experiment. Unless it is done in the right 

 way it is likely to be disappointing and the right way involves 

 both the selection of the best legumes and the best ways to grow 

 them. Scant growth, cloddy soil, loss of moisture and condemna- 

 tion of the practice are likely to result from ill-considered methods. 

 On the other hand, success with cover crops results in such numer- 

 ous and important advantages that the wide introduction of them 

 must be looked upon as one of the most important advances in 

 California horticulture during the last decade. One of the most 

 careful students of cover crops in all their bearings is Mr. L. L. 

 Palmer of North Pomona, who in a recent public address cited 

 ten different reasons for growing cover crops (legumes) in the 

 orchard : 



1. They provide humus in the soil, by which the inert fer- 

 tilization materials of the soil are made available. 



2. They make it possible to obtain results from the use of the 

 cheaper forms of phosphate, such as Thomas Slag and other unacid- 

 ulated phosphates. 



3. They store up nitrpgen from the air, and therefore act as 

 a direct nitrogenous fertilizer. 



4. They improve vastly the mechanical condition of the soil, 

 making it easily possible to secure the best cultivation. 



5. They put the soil in a condition to retain moisture. 





