DANGEROUS INTERNATIONAL FOREST TREE DISEASES 15 



Damping-off caused by Rhizoctonia spp. and Fusarium spp. is a com- 

 mon disease of nursery seedlings of Benguet pine in the Philippines. 

 Two- to six-weeks-old seedlings are most susceptible to this disease. 

 Effective control measures found by experiments are: 40% sulfuric 

 acid (H 2 S0 4 ) diluted in 1,000 cc. of water applied to every square 

 foot of seedbed immediately after sowing the seeds; control of the 

 density of sowing because too dense sowing favors the occurrence of 

 the disease; formaldehyde (40% U.S.P.) diluted with water six times 

 its volume used for treating the soil; and zinc oxide or red copper 

 oxide as soil dressing, the former being more effective. 



Fungi of the genera Trametes and Forties have been observed to 

 infect old and large trees over 60 cm. d.b.h. 



2. Pinus merkusii Jungh. & Devr. (Mindoro pine or tapulau) 



This species occurs in Zambales province and Mindoro Island in 



g laces as low as 100 meters altitude. It is reported to exist also in 

 lurma, Indo China, Borneo, Thailand, and Sumatra. 

 There is no disease so far reported or observed affecting this species. 



Burma 



H. G. Hundley 



Silviculturist, Rangoon, Burma 

 Pinus 



The following species of Pinus occur naturally in the forests of 

 Burma : 



Pinus insularis Endl. (P. khasya Royle.) The Khasi pine. Dis- 

 tribution : Hills of Upper Burma, i.e., the Chin Hills, the Pakokku 

 Hills and between the Sittang and Salween Rivers and the Shan 

 States. Chipwi valley, Hpimaw fort and Ngawchang valley in the 

 Kachin State 2,500 feet a.s.l. upwards. 



Pinus merkusii Jungh. The Tenasserim pine. Distribution: 

 Southern Shan States southward through the hills of the Salween 

 and Thaungyin drainages. 500 to 2,500 ft. a.s.l. 



P. armandi Franchet. Armand's pine. Distribution: Panwa 



and Hpimaw pass, Kachin State. 

 P. walliehiana A. B. Jacks (P. excelsa Wall.) The Blue Pine. 

 Distribution : Lukpyi in Kachin State. 

 Exotic species of Pinus growing in the Botanical Gardens, Maymyo 

 are: 



P. roxburghii Sarg. (P. longifolia Roxb.) The chir pine. 

 P. caribaea Morelet. The Cuban pine. 

 P. halepensis Miller. The Aleppo pine. 

 P. halepensis Miller var. Orutia (Tenore) 1 -p 

 Elwes& Henry. The Calabrian pine. J Fostwar 



None of these have so far been successfully raised in plantations. 

 No research appears to have been done on the diseases of pine. 

 While at Maymyo I have noticed cases of witches'-broom on P. 

 insularis. 



Quercus 



No research appears to have been done on the diseases of Quercus 

 of which there are at least 40 species occurring in Burma. 



