CHANGES ACCOMPANYING BREAKING OF REST PERIOD 51 



the untreated twigs will actually contain more soluble sugar than 

 where treated. 



Special efforts were made to determine whether ether exerts 

 a desiccating influence upon woody tissue. It was found that a dose 

 which results in breaking the rest period has practically no desic- 

 cating effect on the tissue, as the untreated twigs lost just as much 

 moisture as the treated. There was very little moisture lost in any 

 case. When very strong doses of ether were used, large beads of 

 liquid sometimes exuded from the surface of the twigs. Such large 

 doses, however, did not break the rest period but they did injure 

 the twigs beyond recovery. 



From time to time it was noticed that the bark of etherized 

 twigs seemed to change color. Special treatments with ether showed 

 that this treatment tends to hasten changes within the twig which 

 would normally occur in untreated material much later on. 



A correlation was noticed between the amount of sugar avail- 

 able in twigs and the early date at which they were enabled to begin 

 growth. However, untreated twigs, while beginning growth much 

 later than treated ones, often showed a tendency to catch up with 

 and even to outsrtip the treated twigs in point of vigor and amount 

 of growth made. 



It was found by experiment and observation that the respiratory 

 activity of the tissue of dormant twigs may serve as an index to the 

 relative amount of growth which such twigs would make under 

 favorable growing conditions. 



It was noticed that species of fungi nearly always grew upon the 

 cut surfaces of the etherized twigs, while untreated twigs in the same 

 environment showed no infection by the molds except in a few in- 

 stances just at the close of the dormant season. 



It was often observed that etherized twigs, when placed in 

 beakers to grow, seemed to discolor the water. Tests made for the 

 purpose showed that something was dissolved from the twigs by 

 the water, giving the latter different colors. It was found that heat- 

 ing the treated twigs to a sterilizing temperature and also the addi- 

 tion of toluene prevented the coloring of the water extract. The 

 color changes were apparently due to bacteria. 



Wiggans studied the effects of freezing and etherizing on ger- 

 mination of seeds. It was found that freezing soaked seeds reduced 

 the percentage of germination in all cases below that of seeds which 

 were soaked but not frozen. However, it was found if the freezing 

 was followed immediately by etherization, that the reduction 5 ^ in 

 the percentage of germination was not so marked. Apparently the 



