Summary. 
265 
The I’elations of lime and magnesia in soils have been 
studied, and most interesting results have been obtained, both 
as regards the quality of the corn (both wheat and barley) pro- 
duced and the nature of the root growth. It is found 
generally that as the relative proportions of lime and magnesia 
in a soil approach nearer and nearer to the ratio 1 : 1 so the 
wheat grain tends to become more and more glutinous or 
“ hard,” in other words to show more “ strength.” Further, 
the character of the root growth entirely alters, an increasing 
proportion of magnesia to lime developing a root of abnormally 
extensive and fibrous character. These points were well 
illustrated by specimens sent to the Agricultural Education 
Exhibition at the Society’s Show at Lincoln in June, 1907. 
Inquiries have been pursued with regard to the “ acid ” 
condition obtained in Stackyard Field soil as the result 
of the contimied application of salts of ammonia to a soil 
naturally poor in lime. It has been established that the 
failure of plant on these plots is due, not to an actual 
deficiency of soil-constituents, but to the presence of a 
poisonous principle, the nature of which is now being inves- 
tigated. The removal of this by washing with water and 
other means luis been tried, and the harmful infiuence of the 
matter thus removed by washing has been established. Solu- 
tions prepared from the acid soil have been allowed to stand 
and have been noticed to give rise to vegetable growth quite 
different to that which comes when lime water or magnesium 
carbonate are added to the solution. The counterpart to this 
has been observed in the field, in the appearance of the plots 
themselves according as whether the soil remains acid or has 
been neutralised by the addition of lime. The general out- 
come is to lead to the belief that the failure in the field is not 
directly owing to the removal of lime but to the introduction 
of some poisonous principle, or to the growth of certain lower 
forms of vegetation. 
Work has been continued in reference to the extermination 
of weeds, more particulai'ly the wild onion. So far, no 
practical method of applying any “ chemical ” to the soil that 
will directly destroy the wild onion has been found, and 
attention is now being turned to the alteration of the physical 
condition of the soil, whereby this may be rendered such as 
to be unsuited to the ready growth of the weed. Experiments 
in this direction are now assuming a more hopeful aspect, and 
the alteration of the texture of the soil and of its capacity for 
retaining water is being effected by the use of salts which 
tend to aggregate the finer particles of the soil and in-this way 
to improve the drainage. The growing of a tare crop and the 
turning in of it are also being tried, the object being, as above. 
