252 ANNUAL EEPOKTS OF DEPARTMENT OF AOrjCULTUnE. 



nate food plants and the identity of certain confused forms. This 

 Las involved an enormous amount of Avork, and decisive results are 

 about to be reached. 



In addition to the apple insects mentioned above, a considerable 

 number of other species which live in apple orchards have been 

 studied, but most of these are of lesser economic importance in the 

 general run of seasons. As it often happens, however, that one of 

 these minor pests becomes for a season or more very injurious, it is 

 necessar}^ that the bureau should anticipate such outbreaks by secur- 

 ing thorough biological information. 



GRAPE IXSECTS. 



The grape-bekrt :^iotii. — Vineyards were selected in several widely 

 separated sections of the northern Ohio grape belt to serve as object 

 lessons for vineyardists and to give them personal instructions in 

 spraying effectively. It has liecn shown that the grape-berry moth 

 can be controlled bj' two applications of arsenate of lead in spray 

 ibrm, leaving the fruit practically free from residue at picking time. 

 In certain cases a single application has been sufficient, but here 

 th.ere were no surrounding badly infested vineyards. This indicates 

 that eventually a single spray in general Avill keep the pest in checlv. 



The grape MEALYnro. — Full life-history studies of this insect have 

 been finished. Fumigation Avith cj^anid of soda and with sulphur 

 fumes has been satisfactory in the dormant season at night, but 

 sulphur is considered the better. January has been found to be the 

 best time for this work. Spraying has proved less eifective than 

 fumigation, A campaign of education among grape growers has 

 been begun to secure their cooperation in restricting the spread of 

 the pest on picking boxes and in other ways. 



The grape Phylloxera. — In collaboration with tlie Bureau of Soils 

 of this department, a survey of Fresno County has l)een made to de- 

 termine the influence of the physical nature of soils on the degree of 

 infestation of vineyards by the Phylloxera. Interesting and valu- 

 able facts have been ascertained. In\'estigations have been made 

 concerning the best methods of disinfecting grape propagating stock 

 destined for shipment. 



The grape sphi]sjx moth. — An interesting instance of the value of 

 entomological knowledge occurred when this insect appeared in num- 

 bers in Tulare County during the fiscal year, over some TOO acres of 

 vine3'ards. The bureau's agent cooperated Avith the vineyardi.->ts, and, 

 at an outlay of about $12,000 for labor, spraying materials, and ma- 

 chinery, the grape crop, valued at $180,000. Avas saved. 



A number of other grape insects have been studied and new biolog- 

 ical data ascertained. 



NUT insects. 



Pecan insects. — Special attention has been given to the use of 

 insecticides in pecan orchards in Georgia and Florida. Arsenicals 

 are being tried in the form of dusts and sprays, and another season's 

 Avorlv should shoAV conelusively the c()m])arative )ncrits of these two 

 methods. In Texas, the bureau has been especiall,v interested in the 

 ilative pecan groves along river bottoms and elseAvhere. In these 



