~3= 
of the Boerd is as follows: 
Wey 
Bra Ni 
7 i TO + | | 
ethnical employees, including entomologists and pathologists,.113 
Administrative force........... 29 
OUMEYGROR OR Sd Agar nads es eceds Cir icce ee ee 72 
Total. “ps fete en ies : < S A Nf hen te S09 2.9 A. 6 £ (ese Pan S28 08.2 Dae we tes 61st a 
. 6° vrs F SES FAG oh ew Krewe eb ee Oe ot 7 8.958 & €. 2.0 st 2 a eC . ° 14 
TROPICAL AND SUBTROPICAL FRUIT INSECT INVESTIGATIONS 
C. L. Marlatt, Entomologist in Charge. — 
No report has been nade of the activities of this branch of the 
Bureau since October, 1919, 
The force in California under the direction of B.S. Woglum has 
been continuing the experiments with liquid hydrocyahic acid, the in- 
fluence of temperature and sunshine on the killing power offthe gas on 
insects and its effect on trees, ana also on the relationship between 
the use of Pordeaux paste, and the amount of fumigation injury. some of 
| the results of this work are included in two manuscripts submitted for 
_ publication by Mr, Woglum, entitled "Fumigation of citrus plants: enndi- 
“Ws 
tions influencing injury" and "KKK Value of pas-tight covers in orchard 
fumigation." A new formula has been devised for an ant syrup that will 
not crystallize in cold weather. <Avbulletin setting forth the results 
of the Argentine ant work is now in preparation, 
A.D. Borden, in addition’ to his cooperation in the work just out- 
lined, has had charge of a renewed investigation of the twa principal 
scale insects of the date palm and hés been moking. trips from tim2 to 
_time to the Imperial Valley for the purpose of working out details of 
’ life histroy and habits. te Ee oe at 
W.W. Yothers haus retently submitted’ for publication in the Florida 
Fruit Grower an article on "The @ust nethod for controlling rust mites 
on citrus trees," avo 
@,F, Mognette's activity. is partly reflected by the following pa- 
pers which'he has prepared in relation to his work, These have been ar 
will be published in the Journals indicated: 
lies | 
’ 
ish Honduras of a month's duration (February-March). 
The ‘red spider and leaf thrips oh avocado and how they can be 
controlled. (Florida Fruit Grower.) . 
‘The banana root borer. (Journal of Agricultural Research. ) 
A blossom-destroying beetle on the marigo. (Qaarterly Bulletin 
of the. State Plant Bourd of Florida.) ° yn | 
Dusting method versus spraying method for cotrol of insect pests 
on tne avocado. (The Florida Grower.): a 
The Di¢tyospermum scale on the avocado and how it may be con- 
trolled. (Quarterly Bulletin of the State Plant Board of Florida.) 
Some important insects Wiwich attack the avocado in Florida. 
(For presentation at the Annual Meeting of the California Avocado 
Association, Los-Angeles; May 7 ‘and 8, 1920.) 
Insects which attack the avocado in Florida. (For presentation 
at the Meeting of the State Horticultural Society at Ocala, May 4 
£0. Cot BAO.) tie. | 
Dr W.M. Mann has just returned froma trip of exploration in Span- 
It seemed desira- 
ble to obtain a first-hand knowledge of the fruit fly and other insect 
