LUTHER BURBANK 



Mr. Burbank saw in this peculiar habit the pos- 

 sibility of producing a valuable market vegetable 

 that would mature at times when the ordinary 

 pie-plant is dormant. The expectation was veri- 

 fied. Under the changed environmental condi- 

 tions of California, the winter rhubarb developed 

 wonderfully, without hybridization, until its stalk 

 was many times larger than the original plant 

 from the antipodes. Meantime it retained its 

 habit of putting forth stalks most abundantly dur- 

 ing the period of cold weather. 



But of course the winter season in California 

 corresponds with the summer in Australia. So in 

 putting forth its stalks in cold weather at Santa 

 Rosa the plant was modifying its habit radically, 

 as tested by the calendar. That is to say, it now 

 puts forth its stalks in response to the stimulus of 

 cold weather from November to January, instead 

 of from June to August. 



Here, then, was a case in which changed con- 

 ditions of the environment, as marked by the 

 most radical shift of seasons, sufficed to transpose 

 the time of bearing of the plant, twisting it an en- 

 tire half-year out of reckoning. 



But meantime the hereditary clockwork mech- 

 anism within the cells of the plant, through which 

 its time of development had been adjusted for the 

 months of June, July, and August, still main- 

 tained its force; so the plant, thanks to this in- 

 herent impulse and now operating in defiance of 

 environing conditions continued to put forth its 

 stalks abundantly at its accustomed time, which 



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