266 



Journal of Agricultural Research 



Vol. XV, No. s 



Table I. — Results of fumigation of cattleyas imtnediately upon arrival at Washington, 

 D. C, under summer temperature conditions 



Dosage 

 rate, in 

 ounces 



of 

 sodium 

 cyanid. 



4 



Control 



Hrs. 



Conditions 

 under -which 

 fumigated. 



Thoroughly- 

 wet. 



Dry 



Thoroughly 

 wet. 



Dry. 



Wet. 

 Dry. 



.do. 



Number of leaves on — 



Date of fumiga- 

 tion, June 6, 

 1917. 



77 on 12 plants, 

 loi on 12 plants. 

 76 on 10 plants . 



41 on 7 plants . . 



69 on 12 plants . 

 65 on 13 plants . 

 61 on 4 plants . . 

 35 on 9 plants . . 



36 



Nov. 

 191^. 



Num- 

 ber of 



old 

 leaves 



lost 

 since 

 fumi- 

 gation 



Condition on Nov. 22, 1917. 



Plants. 



good. 



3 excellent, 

 fair. 



4 excellent, 4 good, 4 

 fair. 



Poor before fumigation; 



I excellent, 2 good, 7 



fair. 

 Poor before fumigation; 



3 good, 2 poor, 2 



missing. 



5 good, s poor, 2 miss- 

 ing. 



I excellent, 1 good, i 

 poor, 2 missing. 



Good, although i plant 

 lost 15 pseudobulbs. 



Good ; pseudobulbs not 

 counted. 



> a 



CS O 



69 



40 



" Ten growing. ^ Eleven growing 



c One poor. <* Four growing. 



Fourteen growing. 



Table II. — Summary of experiments to determine penetration and effect of hydrocyanic' 

 acid gas on cattlevas held unplanied for one month prior to fumigation. All box fumi- 

 gations were conducted under normal atmospheric conditions 



Treatment before, during, and after 

 fumigation. 



Dry, wrapped 2 hours before fumiga- 

 tion and kept wrapped 24 hours 

 after fumigation 



Same as above, except wet 



Same as above, except dry 



Same as above, except wet 



Dry, held in dark 2 hours prior to 



fumigation; not wrapped when fumi- 

 gated 



Wrapped in heavy paper 2 hours be- 

 fore fumigation and kept wrapped 

 24 hours. 



Same as above, except wet 



Under canvas 2 hours before fumiga- 

 tion; not wrapped when fumigated 



Control 



Hrs, In 



26 

 26 

 26 

 26 



(0 



'F. Pel 

 60 

 60 

 60 

 60 



Number, when 



fumigated July 



30, 1917, of- 



Number, Nov. 22, 

 191 7, of — 



Leaves. 



2 g 

 O Z 



> 9 

 a 2 



■O at 



51 

 ^ 3 



5^ 



ij IS 

 o 40 

 o 40 

 o' 18 



17J4 



"■ Six in poor condition. 



b Eight scarred. 



