CONTENTS. 



Department Bulletin 111. — The Sequoia Pitch Moth, a Menace to Pine 

 in Western Montana: 



Introduction 1 



Description of the insect 1 



Life history 2 



Relation to the mountain pine beetle 4 



Habitat 4 



Host trees, and character of injury 4 



The work of the larva 5 



Effect of the infestation on tree growth and the forest 7 



Secondary injury by fire 8 



Topography of the area 9 



Remedy 10 



Recommendations 11 



Department Bulletin 112. — The Oat Aphis: 



Introduction 1 



Distribution 2 



Descriptive 2 



Species likely to be confused with the oat aphis 4 



Host plants 6 



Injuries and method of work 7 



Causes of occasional outbreaks 9 



Life history of the insect 9 



Natural checks 13 



Remedial and preventative measures 14 



Department Bulletin 113. — -The Lesser Bud moth: 



Introduction 1 



History of the species in Europe 2 



Distribution of the species 3 



Food plants 3 



Character of the injury 4 



Synonymy * 4 



Description of the lesser bud moth 4 



Life history and habits 5 



Insect enemies 11 



Experiments in control 11 



Recommendations for control 14 



Literature cited 15 



Department Bulletin 114.— Report Upon the Black and Boggy Swamps 

 Drainage District, Hampton and Jasper Counties, S. C: 



Introduction 1 



General description 2 



The survev 7 



Run-off. ., 8 



Plan of improvement 9 



Estimate of cost 19 



Maintenance 20 



Conclusions 21 



Department Bulletin 115. — Gate Structures for Irrigation Canals: 



Introduction 1 



Materials used . v 2 



Types of gate shutters 3 



Gate stems and lifting devices 9 



Paving and riprap 10 



Gate structures in open channels 11 



Bifurcation works 21 



Division gates 23 



Lateral headgates 31 



Delivery gates 39 



Check gates 45 



Sand gates 54 



Waste gates 59 



