CITRUS scab: its cause and control. 



33 



Table 11. — Spray schedules for the control of citrus scab in Florida. 

 No. i.— For Orchards Where Citrus Scab Is Always Serious.^ 



Application. 



Time of application. 



Materials used. 



Object and remarks. 



First 



Just before growth 

 sets in. 



In height of bloom 



Bordeaux mixture, 3-3- 

 50, plus 1 per cent oil 

 as emulsion. 2 



Bordeaux mixture, 3-.3- 

 50, plus 0.5 per cent 

 oil as emulsion. 2 

 do 



To cover old%cab lesions. Direct the 





spray especially toward the under 

 surface of the leaves; reduces very 

 early citrus-scab infection. 



For the protection of expanding 

 leaves and smaU fruit against scab 

 and melanose. 



For the protection of small fruit 

 agamst scab and melanose. 



Advisable if the season is rainy. For 

 protection against scab; will also 

 reduce early melanose infection. 



Third 



Fourtli 



Two weeks after third 

 application. 



Bordeaux mixture, 3-3- 

 50, plus 1 per ceiit oil 

 as emulsion. 





Caution: Insecticidal applications must follow to prevent serious scale injury. 



No. ;?.— For Orchards Where Citrus Scab Varies from Moderate to Serious.^ 



First. 



Second. 



Third. 



Fourth. 



Just before growth 

 sets in. 



In height of bloom . 



Two weeks later 



Two weeks after tliird 

 appUcation. 



Bordeaux mixture, 3-3- 

 50, plus 1 per cent oil 

 as emulsion. 



Lime-sulphur solution, 

 1 to 40, or Bordeaux 

 mixture, 3-3-50, plus 

 0.5 per cent oil as 

 emulsion. 



do 



Bordeaux mixture, 3-3- 

 50, plus 1 per cent oil 

 as emulsion. 



To cover old scab lesions. Direct the 

 spray especially toward the under 

 surface of the leaves; reduces very 

 early citrus-scab infection. 



To protect expanding leaves and 

 smaU fruit from scab and melanoses 

 If the season is normal use lime- 

 sulphur; if the season is rainy use 

 Bordeaux mixture. 



To protect smaU fruit from scab and 

 melanose. If the season is normal 

 use hme-sulphinr; if the season is 

 rainy use Bordeaux mixture. 



If the season is rainy, probably ad- 

 visable for protection of smallest 

 fruits against scab; will also reduce 

 early melanose infection. 



iVo. 3.— For Orchards Where Citkus Scab Is of Minor Importance. & 



First 



Just before growth 

 sets in. 



In height of bloom 



Lime-sulphur solution, 

 1 to 30. 



Lime-sulphur solution, 



1 to 40. 

 do 



To cover the old scab lesions. Direct 





the spray especially toward the 

 under surface of the leaves; pre- 

 vents early scab infections. 



To prevent infections on expanding 

 leaves and small fruit. 



To prevent infections on expanding 

 leaves and small fruit. Advisable 

 only when the season is especially 

 favorable for scab development. 



Third 









1 To insure bright clean fruit at harvest time foUow schedule No. 1 with the regular scale, white-fly, and 

 rust-mite spray apphcations (see Fanners' Bulletin 933), one or two additional appUcations of which should 

 be used to check the heavy increase of insect pests following copper sprays. 



' Prepare 3-3-50 Bordeaux mixture in the usual way. Three quarts of oil emulsion, Government formula, 

 in 50 gallons of Bordeaux mixttue gives 1 per cent oil. Add the oil emulsion to the Bordeaux mixture while 

 the latter is being thoroughly agitated in the spray tank. Keep up the agitation while spra3dng. 



Preparation of boiled-oil emulsion, Government formula. 



[See U. S. Dept. Agr., Farmers' Bulletin 933.] 



ParaflBn oil gallons. . 2 



Water gallon . . 1 



Fishoil soap pounds. . 2 



Put oU, water, and soap into a kettle or other vessel that wUl stand lire and heat to the boiling point. 

 While stiH very hot, but after removal from the fire, pump the material into another vessel with a bucket 

 pump and then pump back again. 



3 To insure clean, bright fruit at harvest time foUow schedule No. 2 with regular scale, white-fly, and 

 rust-mite spray applications. When Bordeaux mixture is used additional appUcations of oil emulsion 

 most likely will be necessary. 



< Lime-sulphur solution has not proved effective in melanose control. 



6 To insure clean, bright fruit at harvest time follow schedule No. 3 with the regular scale, white-fly, and 

 rust-mite spray applications. 



4573°— 23— Bull. 1118 3 



