MANURES AND HUMUS IN SOIL. 153 
‘‘Why, here is the best indication yet of whether 
alfalfa will thrive in a field. If the black birds fol- 
low the plowman it is sure to grow; if no black birds 
come let him beware how he sows alfalfa.’’ It is 
indeed a true indication for all eastern soils; there 
may be lands in the South and West where the earth 
worm is not a sure indication. Earth worms thrive 
only where there is humus in the land. They do a 
most useful work in opening the soil by means of 
their tunnels to let in air and let out water. They 
bury up vegetable matter and promote bacterial 
life. Where earth worms are the soil is evidently 
drained, although it may not be drained deep 
enough. 
Alfalfa Loves Rich Soils—The plain truth is that 
thousands of men all over the eastern states of 
America have tried to grow alfalfa on land too poor 
for it. Alfalfa loves fertile soil. In turn it adds 
greatly to the fertility of any land on which it grows. 
It is an energetic soil enricher, but it will not en- 
rich poor soils. That may be a pity, but it is after 
all in the order of Nature. ‘‘To him who hath shall 
be given.’’ One must have fertility in order to trap 
more fertility. No other available plant will gather 
so much fertility as the alfalfa plant. <A field of it 
will gather nitrogen largely, the hay may be fed, 
the manure saved, another field enriched and sown 
to alfalfa and thus the fertility will spread from the 
one spot of infection till all the farm is covered. 
But only by beginning right, by making one field 
rich and dry and sweet, getting it set in alfalfa, 
