December, 1911i] 



511 



Plant Sanitation. 



Lime Sulphur. 



Lime sulphur is one of the few simple 

 sprays which we have that has insecti- 

 cidal and fungicidal properties, and for 

 this reason it is becomicg more and 

 more popular. The only objectionable 

 feature is the boiling which takes from 

 40 to 60 minutes. The formula is as 

 follows :— 



Fresh lime 

 Flowers of sulphur 

 Water 



pounds 20 

 15 



gallons 60 



Place the sulphur in an iron kettle and 

 add 1 or 2 gallons of water, making the 

 whole into a thick paste ; heat, and 

 when the mixture reaches the boiling 

 point add the lime, Sufficient water 

 must be added from time to time to 

 slake the lime, after which the mixture 

 is left to boil until it becomes a dark 

 olive green ; this generally takes from 

 40 to 60 minutes. After the mixture has 

 been thoroughly boiled, sufficient water 

 is added to make 15 gallons, then it is 

 strained and the remaining 45 gallons 

 of water are added. This water does 

 not need to be heated, as the boiled 

 portion of the spray contains sufficient 

 heat to keep the mixture warm while it 

 is being put on the trees. It should be 

 applied warm, although good results 

 have been obtained with cold lime-sul- 

 phur spray. In making large quantities 

 of this mixture steam should be used for 

 boiling. 



Lime-sulphur spray was applied to 

 two rows of orange, grape-fruit, and 

 lemon trees in the experimental grove to 

 compare the result with that from other 

 sprays. This spray was made of 20 

 pounds of unslaked lime, 15 pounds 

 sulphur, and 60 gallons water. All the 

 crawling young scale and full-grown 

 male scale and also a high percentage 

 of females with eggs were found dead. 

 This spraying was done on January 

 16, 1907, and eight days later no crawl- 

 ing young were found. The results with 

 lime-sulphur are not equal to those 

 obtained with the miscible oils made 

 with kerosene, paraffin, or crude oil, 

 but they are tar superior to the results 

 obtained with the kerosene emulsion. 

 The cost of the lime-sulphur wash is 

 about the same as that of miscible oils 

 1 to 20, but as it is advisable to use the 

 oil 1 to 25, or in some cases 1 to 30, it 

 makes the cost of the latter less than 

 that of lime sulphur. 



Lime sulphur is not only a good in- 

 secticide, it also has fungicidal pro- 

 perties. In groves where lime sulphur 

 has been used there is practically no 

 scale and very little rusty fruit. While 



this spray was used for the purple scale, 

 it also held the rust mite in check. 



Great care should be taken in applying 

 a fungicide unless it contains some 

 insecticidal properties. The various 

 scales are oreyed upon by beneficial 

 fungi, which are sure to be killed by 

 the fungicides ; therefore it is recom- 

 mended to apply an insecticide before 

 or just after using a fungicide, so that 

 the scale will not get so vigorous a start 

 and injure the fruit ; or it is still more 

 practical to apply a spray which is in 

 itself a fungicide and an insecticide. 

 Lime sulphur seems to meet these two 

 qualifications. This spray has at least 

 two advantages over the oil emulsions ; 

 it remains on the trees and fruit for 

 three to four months, and during this 

 time seems to retain some of its bene- 

 ficial properties. When it dries it is 

 white, and thus one can readily see 

 what part of the tree has been left 

 unsprayed. 



The fungicidal properties of lime 

 sulphur do not remain on the trees as 

 long as Bordeaux mixture. This has 

 been observed in a grove where Bor- 

 deaux mixture was used, and the bene- 

 ficial fungi did not begin to control the 

 scale until after the first year. Lime 

 sulphur was applied in the same grove, 

 and at the end of six months beneficial 

 fungi had established themselves and 

 were checking the work of the scale. 



Caustic Soda and Sulphur Wash. 



The following formula has been used 

 extensively for red spider and rust mite 

 in Florida :— 



Flowers of sulphur 

 Caustic soda, 98 per 



cent. 

 Water 



pounds 20 



„ 10 

 gallons 20 



For spraying use 2 gallons stock emul- 

 sion to 50 gallons of water. This 

 strength kills the mite and spider, but 

 not their eggs. Sulphur may be added 

 to kerosene and crude-oil emulsions as a 

 remedy for mite and red spider. 



Although the ant is a biting insect, 

 very unsatisfactory results have been 

 obtained by the use of stomach poisons 

 as ants will only eat the bait for a little 

 while. By the use of contact poisons 

 ants can however be combated. The 

 following formula has been used with 

 great success :— 



Water ... quart 1 



Soap (Good's caustic 



potash or Fairbank's 



blue cloud soap ... pound £ 

 Crude carbolic acid, 100 



per cent, (dark) ... pint 1 



