338 THE MONTHLY BULLETIN. 



On the sprayed twigs a large percentage of the scales contained the 

 fungus which was radiating out from the edge of the scales. 



During the latter part of February and the first part of March two 

 samples of the bread media used for inoculating groves were sent to 

 Professor Fawcett by one of the county horticultural commissioners. 

 A microscopic examination and plate culture of both of these samples 

 were made by Professor Fawcett, and although the Isaria fungus may 

 have been present, both of these methods failed to reveal it. Instead, 

 liowever, common Mucor and Penicillium fungi were obtained in 

 abundance. 



In addition to the experiments above recorded, observations have 

 l)een made at different times on many of the groves that have been 

 inoculated commercially by the Isaria fungus. 



SUMMARY. 



The results of the experiments outlined and the general observations 

 in the groves treated may be summarized as follows: 



1. The effect of the Isaria fungus growing under suitable conditions 

 in a moist chamber, either in the laboratory or the field, was found to 

 kill a fair percentage of the black scale. 



2. The results in attempting to disseminate the fungus artificially 

 under natural conditions in the field, at least at the season indicated, 

 have been wholly negative. 



3. From observations made in the various groves where the fungus 

 has been disseminated commercially, there is absolutely no evidence, 

 thus far, to show that the fungus has been of any importance whatever 

 in checking the scales. 



4. Where natural conditions are favorable for the development of the 

 fungus, as in the district contiguous to the coast in Santa Barbara 

 County, the Isaria will kill more or less of the black scale, but the field 

 where it would thrive cannot be greatly enlarged, if at all, by attempts 

 at artificial dissemination. 



5. From our recent experiments and observations as well as general 

 observations made on this fungus since 1908, the writers feel justified 

 in extending to citrus growers no hope that this fungus will keep their 

 trees free from the black scale. 



REPORT OF THE COMMITTEE APPOINTED TO INVESTIGATE 

 THE ARTIFICIAL CONTROL OF THE BLACK SCALE BY 

 FUNGI IN LOS ANGELES COUNTY. 



]\lr. William Wood of Los Angeles has felt that his work as county 

 horticultural commissioner of Los Angeles County is embarrassed by 

 claims that the black scale has been controlled by the artificial dis- 

 semination of a fungus. 'Mr. D. D. Sharp, county horticultural com- 

 iiiis,sioner of Riverside County, has also expressed uneasiness regard- 

 ing the same matter. This led to a call of a committee to investigate 

 the orchards which are claimed to have been treated with satisfactory 

 results. The following is the report of the findings of said committee : 



We, the undersigned, a committee appointed by the Horticul- 

 tural Commissioner of the State of California and of the county 



