98 



mentions the occurrence of stilt-roots in marshy forests, in which 

 Alnus glutinosa predominates while isolated Qnercus pcdunculaia, Rhamnus 

 Frangula and Salix cinerea occur. 



A tliird cause of the stilt-like growth still remains to be mentioned 

 which is different in that the trees are positively elevated, while, in the cases 

 already mentioned, the base of the trunk remains at the place where the seed 

 was sown. White^ describes occurrences of this kind. He thinks that on 

 rocky soil, where the roots must grow flat, the trees are gradually forced 

 out of the ground by periods of frost and draught to which they are peculiarly 

 susceptible. 



c. Too Deep Planting. 



Too Deep Planting of Trees. 



Almost all our trees, in their later life, stand in a position different from 

 that of the seed beds in wdiich they develop. For fruit trees must have a sec- 

 ond transplanting when young in order to obtain an abundant ramification of 

 the root body. Since these trees must be so transplanted great care should be 

 taken that they are not planted deeper than they originally stood. Exper- 

 ience teaches that trees can indeed be destroyed through a disregard of this 

 warning. In fact many practical workers recommend that each tree in its 

 new position be oriented exactly as before in regard to the points of the 

 compass, since they think that many kinds of bark injuries from heat and 

 frost can thus be avoided. 



Otto- has attempted to decide the ciuestion whether the branches of 

 apple, pear and cherry trees develop differently in the several points of the 

 compass. By chemical analysis, he found essential differences in the com- 

 position of the differently oriented one year old branches. The water and 

 nitrogen content is the smallest on the east side, while the content in dry sub- 

 stances is the greatest there ; but the water and nitrogen content is greatest on 

 the north side. This would indicate that the branches were not so fully ma- 

 tured here as on the other side of the tree. 



Kovessi^ considers the cause of a decreased formation of blos- 

 soms to be the greater amount of water and the lesser ripening of the wood 

 of the branches. The number of blossoms and fruit was certainly proved 

 to be dependent on the water supply of the previous year. The tree bears 

 better, if the water supply is scant. Anatomically, the differences in the 

 maturity of the branches, according to the points of the' compass, can scarce- 

 ly be determined since the structure of the same annual ring fluctuates too 

 greatly within the different internodes of a branch*. 



1 WTiite, Theodore, Mechanical elevation of the roots of trees. The Asa Gray- 

 Bull. Cit Bot. Jahresb. 1897, L p. 85. 



2 Otto, Arbeiten der Chemischen Versuchsstation zu Proskau. Cit. Bot. Cen- 

 tralblatt 1900, Vol. 82. Nos. 10-11. 



3 Kovessi, P., LTeber die Beziehung des Wassers zur Reife der Holzpflanzen. 

 Biedermann's Centralbl. 1902, p. 161. 



* Sorauer, Beitrag zur Kenntnis der Zvveige unserer Obstbaiime. Forsch. a. d. 

 Gebiete d. Agrikulturphysik, Vol. Ill, Part 2. 



