33o TEE POPULAR SCIENCE MONTHLY 



thenium incanum), does not produce retonos, as does the guayule, but 

 sends up each season new shoots from the base of the trunk. These 

 shoots root independently and in the course of events are separated by a 

 constriction of the connecting tissue from the parent plant so that an 

 old mariola plant is really a cluster of partially or wholly independent 

 individuals. Such behavior is absent from guayule under normal con- 

 ditions, but may be readily induced under irrigation, and in this way 

 there is afforded the means of vegetative propagation which stands in 

 lieu of the usual method of making cuttings, which has not been found 

 possible up to the present. 



The question which many will ask, whether it will pay to cultivate 

 guayule, must remain, for the present, unanswered. That guayule may 

 be propagated under cultural conditions, both by seed and vegetatively, 

 has been demonstrated. That there are immense areas adapted to 

 guayule and now almost profitless is almost equally sure. The problem 

 seems to be how to get the plant started and to determine to what 

 extent temporary irrigation, by manipulation of the run-off, will be 

 justified on practical economic grounds. An experiment of large 

 scope could be conducted so as to answer these questions and might 

 reveal a new means of increasing our resources. 



