39 



observations. His classification of the sand-deserts will be 

 referred to later. 



The Petersburg Forestry Journal (1901) contains an im- 

 portant article by W. PALEZKIJ on "Sand-binding on the Mid- 

 Asiatic Railroad", and a later contribution has appeared in the 

 Russian Forestry Journal (1908 nos. 31 and 32). The author 

 has for many years superintended the operations for the 

 protection of the Transcaspian railroad against sand-drift, - 

 and in 1899 I had the pleasure of visiting parts of this un- 

 dertaking under his able guidance. 



The paper begins with description of the features of the 

 different landscapes and the dune-formations, the dangers 

 arising from sand, and the different ways in which the drift 

 may block the railroad. 



The most effective means of settling the sand-drift is to 

 encourage vegetation; artificial means such as the planting of 

 green turf and reeds are also resorted to. Trees are planted 

 extensively along the railroad in belts 425 to 530 metres wide. 

 Later on these spread naturally and have in some places 

 reached a width of 2 3 kilometres. 



The natural conditions of the sand-deserts are extra- 

 ordinary, he says. It does not rain from May till November, 

 and the precipitation during winter and spring is insignificant. 

 Ground-water containing bitter-salt, moving sands and the 

 broiling heat of summer are other impediments to a luxuriant 

 vegetation. In combating the sand it is therefore necessary 

 to select local plants acclimatised to the conditions, and 

 sufficiently aggressive to establish themselves. Experiments 

 with introduced plants are, however, also made. The prin- 

 cipal species used for planting are: Saxaul (Haloxylon Am- 

 modendron), Salsola Arbnscula, Ammodendron Conollyi, Ere- 

 mosparton aphyllum, Salsola subaphylla, Smirnoivia turkestana, 

 Astragalus paucijugus and A. Ammodendron, Aristida pennata, 

 Carex physodes and various species of Calligonum. Short 

 notes on their properties are given which we shall refer to 

 later on. 



Nurseries have been established in which stocks are raised 

 for transplanting. As the desert plants often have very long 

 roots which would be damaged by transplanting, the nursery 



