DEPARTMENT OF AGRICULTURE BULS. 1226-1250 



Pag* 

 Depabtment Bulletin No. 1231. — Tests of Methods of Pbotecting 

 Woods Against Termites or White Ants. A Progress Report: 



Introduction 1 



Description of experiments 2 



Treatments for timber to be set in the ground 9 



Superficial treatments 9 



Impregnation treatments 10 



Other treatments 12 



Treatments for wood products not to be set in contact with the 



ground or in wet situations 12 



Termite-resistant woods 14 



Poisons for wood-pulp products 15 



Summary 16 



Department Bulletin No. 1232. — Damage by Termites in the Canal 

 Zone and Panama and How to Prevent It: 



Introduction 1 



Geographical distribution 2 



Relative damage by the families of termites 4 



Kalotermes tabogae Snyder 5 



Cryptotermes thompsonae Snyder 6 



Leucotermes tenuis Hagen 6 



Injury to living crops 8 



Coptoiermes niger Snyder 8 



Injury to lead-sheathed cable in the locks of the Panama Canal__ 9 



Damage to living trees 12 



Swarming 13 



A possible mechanical carrier of the nematode Aphelenchus coco- 



philus which causes ' 'red ring' ' disease of coconut palm trees 13 



Composition of shelter tubes 16 



Nasutilermes cornigera Motschulsky 16 



Swarming 17 



Nasutitermes ephratae Holmgren 18 



Injury to electrical insulation 18 



Possible mechanical carriage of nematode 19 



Composition of shelter tubes 20 



Nasutitermes columbicus Holmgren 20 



Subulitermes zeteki Snyder 21 



Eutermes debilis Heer 21 



Anoplotermes gracilis Snyder 22 



Termite-like shelter tubes of an ant 22 



Control 22 



Literature cited 25 



Department Bulletin No. 1233. — Forest Types in the Central 

 Rocky Mountains as Affected by Climate and Soil: 



Introduction 1 



The method of study 4 



Description of the localities studied 7 



The growing season 25 



Absolute and comparative conditions in the various forest types 27 



Air temperatures.' 27 



Wind, humidity, and evaporation 52 



Soil temperatures 84 



Sunshine 111 



Precipitation 115 



Soil moistures 120 



Recapitulation 131 



General character of the climate 131 



Temperatures and temperature gradients 133 



Wind, humidity, and evaporation 135 



Winter soil temperatures 136 



Precipitation and soil moisture 138 



Conclusions 140 



Applications 149 



Literature cited 151 



