Till! IIKI'ORT OF THE [19 



I have not seen anything like this degree of havoc by parasites among the San Jose 

 scale, jet it doubtless has its foes among both insects and fungi. Prof. Forbes, State 

 Entomologist of Illinois, reports in Bulletin No. 5G, that he has discovered in Sphaero- 

 stil'oe coccophila, Tul, found by Prof Rolfs on the oak scale in Florida, an efficient fungous 

 disease for the San Jose species. Most of the bulletins report that a little coccinelid 

 beetle, Pentilia mesilla, preys actively on the San Jose Scale, and also that in some local- 

 ities the twice stabbed lady-bird, Chilocorus bivulnerus has literally cleared the tree of the 

 scale. Certain species of mites also prey upon it. On specimens collected in South 

 Kent, I found a mite apparently feed ng on the scale which Mr. Marlatt pronounces a 

 species of Rhyncholophus and another much more common not yet determined.* 



Mr. John Gordon, above cited, has been experimenting with the application of hot 

 steam and a small proportion of coal oil. He is making use of one of his neighbor's 

 trees that was nearly killed with the scale as an example of this method of treatment. 

 (Specimen cattings from this tree were exhibited. Branches cut ofi before the treatment 

 still had numerous young scale larvae running over them ; while upon cuttirjgs taken 

 from the treated branches no surely living scale could be found.) Mr. Thonger as ?ured 

 me that Dr. Fletcher had reported 97 per cent, of the scale dead on the samples taken 

 from the trees he had treated with a mechanical mixture of coal oil and water. The 

 machine mixes the oil and water in definite proportions at the nozzles and projects the 

 mixture as an " atomized " spray. Mr. Thonger seems to have confidence that if he had 

 been allowed to repeat his spraying with the coal-oil mixture he could have eradicated 

 the scale from his orchard. 



Up to the present time ihe most successful and satisfactory method of remedial 

 treatment is the fish-oil and potash soap solution. This is a soft soap made with a special 

 fish-oil and strong caustic potash, dissolved in water in the proportion of two pounds to 

 the gallon. Accounts of the demonstration of the success of this kind of treatment on a 

 large scale as made at Catawba Island, Ohio, under the direction of Prof. F. M. Wtbster 

 and Mr. Willis H. Owen have been published and extensively circulated. 



As Prof. Webster is here to-day I will leave it to him to describe the treatment and 

 its results. The potash soap treatment was found to affect the trees so favorably there 

 that growers who had not the scale in their orchards have used it generously. Mr. Owen 

 said that over 17 ions were used last winter on an area considerably less than 1,000 

 aqres. Mr. J. W. Gamble, President of the Ottawa, Ohio, Horticultural Society, for his 

 annual address, read a paper entitled " The San Jose Scale as a Blessing in Disguise." 

 His argument was that the scale had indirectly led the growers to discover the value of 

 the soap as a general cleaner-up and fertilizer of their trees, and on peach-trees it had 

 checked the destructive leaf curl. 



When the scale was first discovered in Ontario, the peop'e thought it was confined 

 to two or three situations and within narrow limits at these places. Had that been the 

 case no wiser course could be taken than to cut down and burn the trees It soon became 

 evident that it was much more widely established than at first suspected. The axe and 

 fire is a primitive method of treatment for insects. Here is one that lives on the surface 

 and has not the power, save in a restricted degree for a short period, of moving it3 posi- 

 tion. Surely science will not remain helpless and useless to kill that exposed insect and 

 save the valuable tree upon which it feeds. In several instances more money has been 

 spent in going over a tree with lenses to discover whether the scale was on it than it 

 would have cost to spray it thoroughly. Drenching with the spraying machine will reach 

 the parts that the lens will miss. The axe and fire method is dependent on the discovery of 

 the insect and discovery is not always possible. Several other species of scale are liable 

 to be mistaken for the San Jose one. By the fire method mistakes are irremediable ; by 

 the spraying method no harm c^mes to the tree though it be drenched with soap suds 

 for harboring one of the native species of scale. 



* Respecting the last, Dr. Howard wrote on the 23rd Oct., "'I have to inform you that your scale mite 

 has been examined by Mr. Banks, and he identifies it, with some little doubt, as Hcmisarcoptcs coccisugus, 

 ljign. If not this species it is a closely allied one and belongs to the family Canestrinidse. The species is 

 the only one known in the genus, and is a parasite of Coccidse, having been found in this country on the 

 oyster-shell bark-louse, and in Europe on other scale insects. 



