THE STEMS 73 



While it is the rule that, under the conditions which prevail in fields 

 receiving customary cultivation, each grain sown yields only a very few 

 straws, there are nevertheless numerous records of very prolific plants 

 arising from single grains sown in open rich ground and freed from 

 competition with neighbouring plants. Patrick Shirreff mentions one 

 with sixty-three ears containing 2473 grains, and another with eighty 

 ears yielding 4522 grains ; Haberlandt also refers to one bearing 130 ears 

 which produced 6855 grains weighing 218 grams. 



By dividing a tillered plant into separate parts, each with its ad- 

 ventitious roots, and transplanting the detached shoots into good ground, 

 a very large number of ears and grains may be obtained in one season from 

 a single grain. 



C. Miller gives an account of the result of an experiment illustrating 

 this method of increase. He states that he sowed a grain of wheat on 

 June 2, 1765, and on August 8 lifted the plant and divided it into 

 eighteen parts ; the several shoots were then planted out singly and the 

 division and transplanting repeated in September and October of the 

 same year, sixty-seven plants being obtained. A third division and 

 planting was carried out between the middle of March and the I2th of 

 April in the succeeding year, producing 500 plants which at harvest 

 yielded 21,109 ears and 47 Ibs. 7 oz. of grain, the estimated number of 

 grains deduced by calculation after counting and weighing a certain 

 number being 576,840. 



Incidentally, it may be noted here that as a process for the multiplica- 

 tion of new varieties of wheat, Miller's system of division and transplanting 

 does not lead to such rapid increase as the practice of thin seeding ; for, 

 as ShirretT points out, the single grain which Miller used was sown early 

 in June, and must have been obtained from the previous year's harvest, 

 two years being required, therefore, to produce one crop. On the other 

 hand, the plant mentioned by ShirretT, which from one grain produced 

 2473 in the first year, would yield 6,115,729 grains at the harvest of the 

 second, or more than ten times as many as Miller's plant, if those obtained 

 in the first season were each as productive in the second as the initial 

 grain. 



The extent of tillering which wheats exhibit is governed by internal 

 physiological peculiarities of the plants, and also by various external 

 causes. 



Most varieties of T. durum, and many of T. turgidum tiller very little, 

 while plants of T. munwofcuni , T. diroccum, T. Spelta, and T. comfmctum 

 usually give rise to a number of straws ; even varieties of the same race, 

 very similar to each other in form of ear and other morphological char- 

 acters, often differ in branching and in stem production. Late forms 

 usually tiller well, early forms tiller very little. The rapid-growing spring 



