KCOXOMIC ZOOI,()<;V KXI()M()I,()(;V. 555 



Erroneous reports of cotton-boll weevil — its present status, F. Siii.kman, 

 Jr. (.V. r. 1)1 pt. Aiir. lUil. Che. ^1, pp. /,).— K<>ports lo tlio cnVct that the eotton- 

 liull weevil lias lieeii fitiuul In Xortii Carolina are deciiired to be without fouiida- 

 tioM. At i)reseiit this inseet oeeurs in eastern Texas, Oklahoma, Arkansas, 

 Loiiisiana, and Mississippi. 



Insect pests and diseases of sugar beets in 1907, O. Fallada (Mitt. Chcm. 

 Tech. Vers. Stat. Cent. \'(i: h'iUxnz. Ofttrrr.-Unfiar., No. 7.97, pp. 2S-37). — 

 I'viii'f accounts are jiiven on the injuries caused to su^xar i»eets l)y mole crickets, 

 wireworms, snout beetles, flea beetles, red spiders, cutworms, plant lice, root 

 worms, nematodes, and other inseet pests. Mention is also made of lo.sses 

 c.-iused by the occurrence of dry rot. scab, bacteriosis, and other funjrus dis- 

 eases. 



Fumigation for the citrus white fly, as adapted to Florida conditions, 

 A. W. MoKKiLL (U. S. Dcpt. Agr., Bur. Ent. liiil. 7li, pp. 7.i, pin. 7, Jigti. II). — 

 I'nmi^'ation experiments with hydrocyanic-acid gas carried on in Florida for 

 two winters, during the short dormant period (December, January, and Feb- 

 ruary), when there were no winged insects, have demonstrated the i)ractica- 

 billty of tills method for the control of the white fly. In an extended discussion 

 of the conditions favoring or necessary to good results, the author considers 

 the isolation of the grove, the importance of concerted action, the absence or 

 elimination of food plants other than citrus, the season of the year, meteorolog- 

 ic.il conditions, and the size of trees and their regularity of setting. It was 

 found that fumigation could safely begin at sundown and that on cloudy days 

 it was safe to fumigate at any time with untreated tents. The effect of wind 

 was found to be so great that fumigation is not recommended when more than 

 u sli-rht l>reeze prevails. It is concluded th;it moisture on the leaves in the 

 form of dew does not reduce the efficacy of the gas in destroying the insects 

 but possibly increases it. 



The many details relating to the equipment and methods of operation includ- 

 ing quality and amount of the chemicals, tents and methods of handling, meas- 

 uring trees, methods of generating the gas, estimation of time required for 

 fiuniKatlon of the grove, and methods of computing approximate dimensions 

 nnd cubic contents are discussed. The bell or hoop tent and the sheet tent ai"e 

 the two styles now in use. 



A formula of 1 part potassium cyanid, 1 jiart sulphuric acid, and ."^ jiarts water 

 and an exposure of 40 or 4~) minutes is reconunended. Elaborate tables are given 

 which show the results obtained from various sized trees at various strengths of 

 pns. When the recommendations here made are followed, appreciable injury to 

 ornn>;e trees will rarely occur and apjiarently never to tangerine and grapefruit 

 trees. As occasional injury to the fruit may occur, it is thought best to pick 

 the crop l)efore starting to fumii;ate. The author reconunends particularly the 

 taking uji of funiit,'iition by the various counties under the direction of their 

 horticultural commissioners. The Florida red scale (ChriisotuiilKtlUH /iciix) and 

 the purple scale ( Lrpidosaplics hrckii), two pests of citrus fruit are controlled 

 by the fumipition for tlu* white fly. 



The entire cost of fumi^^ating a tree measuring 42 ft. over the top from 

 ground to ground and rt'J ft. in circumference is estimated at oO cents. It is 

 further estimate«l that in 2 years the cost of spraying a tri»e of this size would 

 double tile cost of one fumigation. "In a series of ,"> or more years spraying 

 would doulitless cost fully .'i times as much as would control by fumigation, the 

 l«l>or involved would be far greater, and the results far less satisfactory. . . . 

 MiiUiitee Coiiiity is the only larfie orange-growiii;,' district where the fungus 

 diseases have proved of much assistance. . . . One year in three, it is the 



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