LIBERATION OF ORGANIC MATTER BY ROOTS OF GROWING 
PLANTS 
AR IB Lyon AND J. K. WILSON 
In the course of an investigation under way at this station, it became 
desirable to know whether organic matter, particularly that of a nitrog- 
enous nature, is liberated by the roots of growing plants, at least of 
the plants commonly raised on farms in-this region. Numerous investi- 
gations conducted elsewhere have shown that nitrogen is lost by certain 
plants during the late stages of growth, particularly about the ripening 
period. Theré seemed to be a question, however, whether this nitrogen 
escaped from the leaves or the roots, and it had never been shown to be 
in the form of organic matter. The previous investigations had, indeed, 
not touched on the question of the loss of organic matter by growing 
plants, and aside from its bearing on the investigation in hand this appeared 
to be a matter of some scientific interest. 
A closely related question is the possible liberation of reducing or oxidiz- 
ing substances by the roots of growing plants. There had previously 
been some investigation of this subject, but since the experiments on the 
liberation of organic matter furnished exceptionally good opportunities 
for making the tests for catalysts it was decided to try to obtain some 
information to supplement the previous work. 
REVIEW OF LITERATURE CONCERNING LOSS OF NITROGEN FROM 
GROWING PLANTS 
A large amount of work has been reported showing the percentage of 
the various nutritive elements found in crops at certain stages of growth. 
Less work has been done, however, on the actual weight of nutrients in 
plants during their growth and maturity. 
The work of Wilfarth, Romer, and Wimmer (1906) was concerned with 
the assimilation of the elements of nutrition by plants during different 
periods of their growth. This investigation extended over a period of 
about eight years. The experiments included both field and pot work, 
the former with barley, spring wheat, and potatoes, and the latter with 
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