HOW WE HELP TO FEED THE PLANTS. 
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HOW WE HELP TO FEED THE PLANTS. 
1. As far as possible, we should see that what 
plant-food our crops take from the soil is given 
back to it again. If we do not do this, we shall be 
like a man who keeps on drawing his money from 
the bank and never putting any in, until at last he 
has none left. 
We therefore sometimes add manure to the soil, 
that it may help in forming fresh plant-food. 
2. As we know the good that is done by plants 
decaying in the earth, we dig in the weeds, the 
trash from our crops, the foliage of ferns, seaweed, 
or any other vegetation that can be spared. This 
is known as ‘ green manuring ’, because the manure 
is not in a decayed state when we use it. The 
layer of weeds or trash that is often spread in the 
coffee-fields of the Blue Mountains not only does 
good by keeping the ground moist, but also supplies 
new food by its decay. 
3 . Sometimes crops of blackeye peas or cow-beans 
are grown on purpose to be dug or ploughed into 
the ground as green manure. These plants are 
chosen because those of the pea-tribe take nitrogen 
from the air, which most plants cannot do, though 
they need it in the soil. So, when the pea-plants 
are dug in they not only give back to the soil what 
they took from it, but they also carry in a store of 
nitrogen, which they gathered from the air. In this 
