PLATE 25 



A. — Dormant wild crab stimulated to growth by pruning. This plant had remained 

 dormant in the warm greenhouse during the fall and winter at a temperature of 55 

 to 70 F. On April 5 three branches were pruned, and on April 24, when the photo- 

 graph was taken, the uppermost bud on each of the pruned branches had begun to 

 grow. On other, unpruned plants no bud growth had taken place. 



B. — Dormant wild crabs stimulated to growth by girdling and by notching the stem. 

 These plants had had the same preliminary treatment as the one illustrated in A — 

 that is, they had been kept in the warm greenhouse all winter, without chilling. 

 On April 4 a ring of bark was removed from the plant shown in the left-hand figure, 

 and the soft cambium was carefully scraped away, down to the hard wood. On 

 April 24, when the photograph was made, the bud next below the girdle had begun 

 to push. The stem of the right-hand plant was notched in early April. The bud 

 next below the notch soon began to grow. The photograph was taken on May 2. 



