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CLlfiRANS' UST OF FRUITS, 1909 - io. 
Principal Washes used as Sprays 
against Insects and Mites. 
By Mr. F. V. THEOBALD, M.A. 
Reprinted from The Journal of the Royal Horticultural Society, 
Vol. XXXIV., Part III., Appendix A, page 349. 
Inserted by the consent of the President and Council. 
CAUSTIC OR WINTER WASHES. 
Of these we have Caustic Alkali Wash, the Woburn Winter Washes, 
the Lime and Salt Wash, and the Oregon Wash. 
CAUSTIC ALKALI WASH. 
Formula — Caustic Soda (98 per cent.) 2-2J lb. 
Water 10 gallons. 
Uses . — For cleaning old mossy and rough-barked trees in Winter, and 
killing mussel-scale ova. Must be used only on dormant wood. The best 
time is February or March. 
The addition of Paraffin to the Caustic Wash has been found to make 
it much more effectual ; and this Wash, known as the Woburn Wash, is 
made as follows : — 
WOBURN WINTER WASH ( Non- Fungicidal. ) 
(1) Formula — Soft Soap £ lb. 
Paraffin 5 pints. 
Caustic Soda 2 lb. 
Water 9$ gallons. 
Preparation . — Dissolve the soap in warm water, churn the Paraffin 
into it, and then shake in the Caustic Soda. This soap emulsion does not 
seem as good in Winter as the metal emulsion made with iron sulphate. 
(2) Formula — Iron Sulphate £ lb. 
Lime £ lb. 
Caustic Soda 2 lb. 
Paraffin 5 pints. 
Water 10 gallons. 
Preparation. — Dissolve the iron sulphate in 9 gallons of water ; slake 
the lime in a little water and then add more, so as to make it into milk 
of lime ; then run the milk of lime into the dissolved iron sulphate through 
a fine sieve, to strain off all grit : then churn the paraffin into the iron 
sulphate and lime, and finally add the caustic soda. 
