229 



The eight forest nurseries of this Division on the four main 

 islands propagated or distributed a total of 292,081 trees during 

 the past calendar year for general planting throughout the Ter- 

 ritory. Large numbers of shade trees and ornamental plants and 

 vines were supplied to the military posts on Oahu for the beau- 

 tification of quarters. 



Tree planting operations on forest reserves in need of refor- 

 estation for the conservation of water were extended and con- 

 sisted mainly in the planting of koa trees on well drained soil. 

 A large variety of other trees, not used before in extensive plant- 

 ing, were also set out in various situations to test their adapta- 

 bility. In this manner 32,648 trees were planted out on the forest 

 reserves in spite of a comparatively dry year. 



Advice and assistance on tree planting and the care of trees 

 has been rendered the public, instruction on tree planting was 

 given at the vocational school for soldiers at Schofield Barracks 

 and lectures on forestry were delivered at the Territorial Sum- 

 mer School and the College of Hawaii. 



Entomology. 



The aim of the Division of Entomology has been to meet the 

 demand for relief from insect depredations; the work, therefore, 

 has been almost altogether practical. 



The propagation and distribution of beneficial insects, particu- 

 larly l]ie fruit fly, horn fly and corn leaf hopper parasites has 

 been continued throughout the year. Also an attempt has 

 been made to acclimatize and establish in the islands Pterofiialus 

 pupanim, a pupal parasite of one of the destructive cabbage in- 

 sects, Picris rapae (cabbage worm, imported cabbage butterfly). 

 A small shipment was received through the co-operation of the 

 California State Horticultural Commission in June, 1919, and 

 thousands of individuals have been reared and liberated. 



No field work has been undertaken, on account of the unset- 

 tled conditions abroad and poor traasportation facilities. 



An investigation was begun early in the year of the natural 

 control of the dungflies in Hawaii, with the purpose in mind of 

 securing additional agents, if conditions warranted it, and so im- 

 proving the control. Considerable time also has been given to 

 the study of the termites, or white ants, which are becoming 

 severely and alarmingly destructive with the increase and spread 

 of two. lately immigrant species. These investigations remain in- 

 complete at the present time. 



In September, 1919, an infestation of the forest ferns by the 

 Australian fern weevil, Syagrius fulvitarsis, was discovered at 

 29 miles from Hilo on the Hilo-Kau road. On account of the 

 wealth of fern growth in this region and the importance of the 

 ferns as part of the ground cover in the Hamakua Forest Re- 

 serve, it was decided to attempt to control the outbreak .irid pre- 

 vent the spread of the weevil beyond the confines of the small 

 area in which it was determined to be present. This necessitated 



