The Roots of the Wheat riant. 



175 



sion that the beneficial action of these substances depends upon 

 their destroying the germinating power of malformed and dis- 

 eased seeds. 



About three years since I planted four plots of wheat in the 

 followine: order : — 



Mucli diseased 



wheat, without 



pickle. 



2. 



Much diseased, 



treated with 



sulphate of copper. 



3. 



Perfect picked 



seed, without 



pickle. 



Perfect picked 



seed, with 



sulphate of copper. 



The results of these experiments were as under : — 



Plot 1. Much of the seed germinated, but the crop vvas 

 much blighted, both in straw and grain : in fact, scarcely 

 a perfect ear of the latter. 

 Plot 2. A very small quantity of the seed germinated, the 



few resulting: ears were free from blight. 

 Plot 3. Germinated, with a good and clean resulting crop. 

 Plot 4. The same result as Plot 3. 

 These experiments show that the pickling of wheat destroys 

 the seed so as to prevent germination when the seed is diseased 

 or ill-formed ; but if perfect seed were always employed, no 

 pickling is at all necessary, it being perfectly true that a 

 diseased progeny must result from an imperfect stock in plants 

 no less than in animals. 



In committing the seed to the ground, theory confirms the 

 practical propriety of sowing neither too shallow nor too deep, 

 as the former renders it exceedingly lialjle to be eaten by birds ; 

 and if so shallow as to be exposed to light and air, the chemical 

 changes attendant upon germination are not so carried on as to 

 ensure the best results. If, again, it be sown too deep, though 

 the first evil be avoided, yet germination beyond a certain deptli 

 is next to impossiljk", and if brought about the foUowing evil is 

 sure to result, namely, the re-rooting takes place at the u])pcr 

 joints, and the lower parts of the original stem and roots die 

 away, thus causing a great loss in the vitality of a plant so cir- 



