DISEASES AND ENEMIES 259 



and the direct damage is increased by the fact that 

 trees covered with dead witch-brooms are very liable to 

 the attacks of the die -back disease (Diplodid). The 

 witch-broom disease has therefore been accompanied by 

 the death of thousands of trees by die-back disease. 



The Kamerun witch - broom disease (probably 

 caused by Taphrina Bussei}. This disease has only 

 been observed in Kamerun, and must not be con- 

 founded with the Surinam witch-broom disease, from 

 which it is quite different. The diseased twigs do not 

 show any hypertrophied growth ; there is only an 

 abnormally abundant development of side - branches. 

 Thus a typical " witch -broom" is developed, and the 

 name of the disease is therefore perfectly appropriate. 

 According to the investigations of Von Faber, these 

 branches and twigs contain a mycelium, and on the 

 leaves was found a fructification due to the parasite, 

 which has been given the name Taphrina Bussti. 

 Until now the disease has not caused much damage, 

 but it is, of course, advisable to remove and burn the 

 witch-brooms. 



Chupon wilt. Rorer, the Trinidad mycologist, 

 observed that the fungus, which is the cause of 

 the "canker" disease and the "black rot" of pods 

 (Phytophthora Faberi), also attacks the young shoots 

 ("chupons"); this disease is called in Trinidad 

 " chupon wilt." Rorer 's description may be quoted : 



This disease was very prevalent on many estates [in Trinidad] 

 last year [1909]. The chupon is generally first attacked in the 

 soft tissue near the tip. A small water-soaked area can be seen 

 on the stem, which gradually becomes sunken and darker in colour 

 and spreads up and down the stem, frequently girdling the shoot 

 and causing the upper part to wilt. The same disease has been 

 observed on young shoots on the upper branches of the tree. The 

 point of attack is generally in the axil of a leaf, though the leaf- 

 blade or petiole may be the first part affected, the disease after- 

 wards running down into the stem. . . . Chupons are also fre- 

 quently killed by aphides or other sucking insects, and such cases 

 should not be mistaken for the disease of fungous origin. The final 

 appearances of the killed shoots are the same, but the initial stages 

 are quite different. 



