202 Amencan Horticultural Society. 



EXPERIMENT.S WITH RESIK COMPOLXD. 



The strongest application of this was made on pear and plum, infested 

 with A.rapnx, August 27; three quarts of the compound to four of water. 

 (Experiment 170) September 4 all traces of waste had disappeared, not in- 

 juring the foliage of plum. The leaves of the pear were very brittle for the 

 first few days, and some tips of older leaves turned black, but none came 

 off, and otherwise no injury was done. An occasional living scale was found 

 October 7. 



One part of the compound to two of water. Applied on February 2"^ on 

 A. rapax on pear. (Experiment 160.) Rain fell for two days following, and 

 the result, i)erhaps, was not as good as it would otherwise have been. A 

 careful examination on March 8 showed that a large part of the eggs had 

 been destroyed, also all the young and many of the older scales. On this 

 tree they did not increase, and on November 21 hardly any living scales 

 could be found. Other experiments were made of the same strength on As- 

 pidiottis sip. on currant, and A. rapax on pear, August 27. (Experiment 17o.) 

 All but a few gravid females were destroyed on pear, and very few remained 

 on such places where they had been in thick layers on currant. October 7, 

 a few young scales were found on both plants, but hardly any were living 

 November 22. The wash disappeared in ten days, leaving the trees in good 

 condition ; no leaves fell. 



Three parts of compound to eight of water were applied on orange 

 thickly infested with Lecnnium heJiperuium September 2. (Experiment 184.) 

 In five days after application no living scales could be found, and on none 

 on November 22. The tree was not at all affected by the wash. 



One part of compound to four of water applied on pear with A. rapax 

 February 28 (experiment 159) destroyed all the smaller and i>art of the older 

 scales, but soon after the scales were increasing again. The same strength 

 was also applied on Diapis ros,x on rose March 8 (experiment 162). This 

 effectively cleared the plant of scales; and again on L. hejiperidum on orange 

 September 2 (experiment 183). All scales were dead on September 7, and 

 none Hving could be found November 22. 



One part of compound to eight of water on L. hesperidum on orange 

 September 2 (experiment 182) destroyed nearly all scales, but many living 

 young were found under mother scales September 7. Only very few living 

 scales were found in tree September 13 and October 7, but on November 

 22 the tree was covered with scales again. 



Other experiments of this strength were made, and may be worthy of 

 mention: On L. dex on orange, and on several peach trees in full blossom, 

 infested with the Lfcanium bred from oak {A. ar/rifJia). Here, also, many 

 of the scales survived. The trees in consequence were loaded with fruit, as 

 well as those not treated. 



E.XPBRIMENTS ON APHID.i: WITH RESIN COMPOUND. 



The woolly Aphis {Schizonoura lanigera), the cabbage Aphis {Aphisbras- 

 sicse), the plum Aphis {Aphis pruni), and Aphis on ra-^e {Siphoiiophora rosa). 



