Practice of Plant Breeding 



only one seed germinated. The plant was an annual 

 and never set any seed ! 



The third method, that of altering the conditions in 

 which a plant lives in order to induce it to change or 

 vary, is also, by report, used by Burbank. It is possible 

 that many plant-breeders possess their own secrets as 

 to culture and treatment. Both Patrick Shirreff and 

 Hallett did endeavour to assist the plant in its efforts 

 to produce better seeds by specially kind cultivation. 



Unfortunately the cold shadow of Weissmannism 

 still discourages experiment in this direction (see below). 



But that plants can inherit the method of growth, 

 &c, induced by special conditions is quite certain. 



At great altitudes in the Alps, trees grow very slowly 

 and shed their leaves at a much earlier date than those 

 at lower and more genial elevations. Some interesting 

 experiments by Engler and Cieslar have proved that 

 these habits can be inherited. 



Seeds of spruce, larch, sycamore, &c, were collected 

 at various altitudes in the Alps and in Austria. Experi- 

 mental gardens were then formed at various places, also 

 differing in altitude, and the different rates and habits of 

 growth were carefully observed and recorded. 



At Adlisberg (2200 feet) it was found that five-year- 

 old spruces grown from Engadine (5950 feet) seed 

 were on an average 9 inches, whilst others from Winter- 

 thur seed (1800 feet) were 18 inches in height. So 

 that those whose parents lived at very great altitudes 

 grew at just half the rate of the others. The other 

 characteristics of their high Alpine parents, such as a 

 very extensive root system and a tendency to branch 

 from the base, were also quite distinct. 



Fifteen-year-old trees from Carinthia gave quite 

 similar results. One set (seed from 1700 feet) were 

 4 feet 5 inches high and grew 4.2 inches in 1905, and 



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