U. C. Experiment Station 
11 
The reactions shown in Table III may not indicate accurately the 
condition under which the crops are grown. Much of the nitrogen as¬ 
similated by the corn grown on the limed plats must be in the form 
of calcium nitrate. The rejection by the plants of the basic radical of 
this salt should tend to maintain a reaction so weakly acid as to protect 
the plant from the soluble ferric and aluminum compounds. 
In soils such as these, high in organic matter and containing exces¬ 
sive amounts of water, the presence of ferrous iron is entirely possible. 
The four-ton applications of lime have not sufficed to make the soils 
alkaline enough completely to precipitate ferrous salts as the hydroxide, 
nor would the calcium bicarbonate rejected by the plant roots effect 
this result. 
The evidence is not conclusive that the unfavorable crop conditions 
in this soil are due entirely to the state of the surface soil. It has been 
observed in some pot cultures that applications of lime up to the rate 
of 15 tons per acre in the surface six inches did not prevent the accumu¬ 
lation of iron in the nodes of corn plants. On removing the soil from 
the pots, however, it was found that the corn roots had failed to pene¬ 
trate into the unlimed subsoil, being matted into a dense growth at the 
junction between the soil and subsoil. Possibly the iron which had 
accumulated in toxic amounts in the plant was absorbed from the un¬ 
limed subsoil rather than from the limed surface soil. 
Several investigators (4, 6, 12) have shown that large applications 
of soluble phosphates aid in the precipitation of these toxic compounds 
of iron and aluminum and Conner (3) has shown that silicates have 
an effect similar to that of the phosphates. It is not improbable that 
the application of large amounts of acid phosphate to these soils would 
be of considerable benefit especially if used in addition to lime. Silica 
appears to be present in sufficient amount so that further application 
would be useless. Extremely heavy applications of lime would be needed 
to bring this soil to neutrality on account of the potential acidity of 
the content of nitrogenous organic matter. Such treatments are, of 
course, impractical and offer no solution to the problems of the farmers 
of the region. Other remedies must be found which are more rational 
though less efficient. 
There is no doubt that present drainage conditions are the funda¬ 
mental cause of most of the troubles experienced with these soils. Sher- 
win, Etheridge and Dunham (13) have reported some of the physical 
characteristics of a typical muck soil from this section but were able 
to offer no practical suggestions for facilitating drainage. Until further 
developments in the solution of this problem, therefore, poor drainage 
must be accepted as one of the limitations of certain soils of this recla¬ 
mation district and treatments are to be prescribed on this basis. 
Profitable use of these soils may be had by raising crops immune to * 
the toxic influence of acid soils though even these crops may be benefited 
by liming and fertilization. The blackberry, dewberry and huckleberry 
