974 



Report on the Treatment of Seeds. 



[JAN., 



is not the amateurish effort that is sometimes supposed. 

 Further, there are no forced or unnatural conditions. In pot- 

 culture work the conditions are made as natural as possible, but 

 precautions are taken to obviate risk of loss by plant diseases, 

 pests, or severe seasonal factors such as prolonged drought, 

 excessive rain, frost, etc. It may be said that as a result 

 conditions in pots are rather more favourable than those in 

 the field in the ordinary run of seasons, and resemble the 

 conditions obtaining in the field in a good season. Hence the 

 differences shown in pot experiments are not always realised in 

 the field : there are, for example, cases where a 20 per cent, 

 improvement in the pots showed up as only a 10 per cent, 

 improvement in a corresponding field test, and other cases 

 where a treatment giving 10 per cent, improvement in the pots 

 gave no certain improvement in the field. There are very 

 few cases, however, where a treatment fails in the pot-culture 

 house and then succeeds in the field. 



The 1 91 8 experiments were made with oats and barley. 

 Soil from ordinary arable land was used. Half of the pots 

 were left unmanured and half were sown with a mixture of 

 artificial manures. Of the unmanured pots half were sown with 

 treated and half with imtreated seed. The results were : — - 



Effect of Manuring, 



Average dry weight per pot of five plants. Two pots in each set. 



Crop. 



No Manure. 



Complete 

 Artificials. 



Increase per 

 cent, due to 

 Manuring. 



Barley. 



grams. 



grams. 





Expt. I. Grain . . 



lyo 



i6-o 



23-1 



Straw . . 



19*6 



35-6 



81 -6 



2. Grain 



9-8 



i6-5 



68*4 



Straw . . ■ . . 



17-4 



33*6 



93*1 



^ , Oats. 







48-6 



Expt. I. Grain . . 



9*25 



13-75 



Straw . . 



20 -o 



36-2 



81 -o 



2. Grain . . 



io*4 



15-8 



51-9 



Straw . . 



i6'o 



36-2 



126-3 



There were four separate tests and eight separate quantities 

 measured, and in every case, without exception, the manuring 

 increased the crop. This is in accordance with the state- 

 ment already made that, when properly done, manuring belongs 

 to the first category of treatment, which nearly always succeeds. 



