SUGGBSTITE CONCLUSIONS. 305 



completing their maturity. A similar process occurs in 

 the union just above the crown of the bulb, indicating 

 the maturity of that organ. Fig. 159 represents the 

 bulb fully developed and mature^ from which the stalk 

 was cut, after the nutritive process was completed, 

 above the point where drying or desiccation had 

 begun. 



4. If the stalk be cut from the tubers before this evi- 

 dence of maturity has appeared, the necessarj' supplies 

 of nutrition will be arrested, their proper growth will 

 cease, and an effort will be made to repair the injury by 

 sending out small, lateral tubers, from which weak and 

 unhealthy stalks will proceed, at the expense of the 

 original tubers. This is seen in Pig. 158. All will ulti- 

 mately perish, either by the droughts of autumn or the 

 cold of winter. 



5. The tubers, together with one or two of the lower 

 joints of the stalk, remain fresh and green during the 

 winter, if left to take their natural course ; but if, by 

 any means, this green portion be severed, at any season 

 of the year, the result will be the death of the plant, 

 when it will appear as in Fig. 160. 



From these five propositions the following conclu- 

 sions are drawn : 



1. That Timothy grass cannot, under any circum- 

 stances, be adapted for pasture, a^ the close nipping 

 of horses and sheep is fatal to the tubers, which are also 

 extensively destroyed by swine, if allowed to run in the 

 pasture. 



2. That the proper time for mowing Timothy is at 

 any time after the ' process of desiccation has com- 

 menced on the stalk, as noted in the third proposition. 

 It is not very essential whether it is performed a week 

 earlier or later, provided it ■ be postponed till that evi- 

 dence of maturity has become manifest. 



26* 



