RESULTS OF TESTS WITH VARIOUS LEGUMES. 25 
RESULTS OF GREEN MANURING IN CALIFORNIA. 
There have been no definite tests made in California to determine 
the results in an increased yield of fruit or improved quality of the 
same from the use of green manures. The only evidence available 
is that of general observation and the experience of the orchardists. 
While orchardists differ to some extent in conclusions, they gener- 
ally are favorable to the practice, as its continued and growing use 
attests. Careful observations also show the beneficial results of 
ereen-manure crops in a more thrifty appearance of the trees, an 
improved condition of the soil, and a better quality of the fruit. 
The belief is quite general that the yield, also, is increased. Orchards 
in which a few years ago there were unthrifty trees with yellowish- 
colored leaves now, after several years’ use of green-manure crops, 
show a decided improvement in color and general appearance. The 
work of the California experiment station has demonstrated that 
eummosis of citrus trees is brought on by unfavorable soil conditions 
and that in remedying such conditions green manures serve a very 
useful purpose.“ Orchards in which green manures have been used 
for a long time are but little affected by this disease. 
The improved condition of the soil when green manures have been 
used for some time has been readily noticeable to those handling an 
orchard. The heavier soils have become quite open and friable and 
the sandier soils more loamy. Beneficial results in the conserving 
of rainfall and the prevention of washing of the soil have also been 
very apparent. Most soils that wash badly do so because they are 
deficient in organic matter. Green manuring, by the improvement 
of the mechanical condition of the soil, not only prevents washing, 
but the presence of the growing crop on the land prevents gullying 
during the rainy season. This is of particular importance on sloping 
lands. 
RESULTS OF TESTS WITH VARIOUS LEGUMES. 
From the fact that the addition of humus to the soil is one of the 
main objects in using a green manure, it necessarily follows that, 
other things being equal, the crop producing the heaviest vegetative 
growth is the most desirable. To determine the comparative 
amount of vegetative growth made by various crops the green weight 
per acre has been determined, as shown in Tables I, I, and III. 
However, these figures can be taken only as indicating in a general 
way the amount of organic matter returned to the soil, as no correc- 
tions were made for the varying moisture content of the different 
crops. 
@ Bulletin 200, California Agricultural Experiment Station. 1908. 
190 
