CHAPTER XXV 
PRACTICE OF PLANT BREEDING 
IT is a very difficult matter to define the just and 
exact relations of theory and practice. 
In theory, theory should lead just as the horse should 
always come before the cart, but in practice this seems 
to be most unusual, 
There are three distinct and separate principles by 
which breeders of plants endeavour to improve their 
special races and strains. The first and most obvious 
course is to select the very best individual plants for seed, 
and to breed entirely from them. The second method is 
that of crossing or hybridising different races or strains, 
and selecting some of the mongrels for further trials. 
The third consists in varying or altering the conditions 
under which the plants are grown, with the object of 
tempting them to produce something unusual or odd, and 
which may be of use. Sometimes these three methods 
are combined. Indeed a great many well-known breeders 
habitually use the first and second principles, The third 
is at present rather unfashionable, but has nevertheless 
produced important results. 
For the sake of clearness and common-sense, we 
shall try to explain first some of the triumphs obtained 
simply by selection of the best varieties. It was by this 
method that Le Couteur of Jersey and Patrick Shirreff 
of Haddington so greatly improved our corn and wheat 
crops. The latter produced the celebrated Hopetown 
oats in 1832, and during forty years of work was able 
to place on the market four distinct varieties, all of 
which were very valuable to his generation. Other 
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