474 INJURIOUS AND BENEFICIAL INSECTS OF CALIFORNIA. 



LIME, SULPHUR AND SAL BORDEAUX 



This mixture is prepared as follows: 



Ilydrated lime (dry, finely powdered, water-slaked lime) 40 pounds 



Flowers of sulphur 5 pounds 



Sal Bordeaux (a mixture of Milestone, charcoal and naphthol)_ 5 pounds 



Mix these ingredients thoroughly and apply with a power blower. 

 This is one of the most efficient preparations now being used in con- 

 trolling the red spider (Bryohia pratensis). 



MILLED SULPHUR. 



This is sulphur to which something else is added to make it possible 

 to grind it exceedingly fine. It is known by the trade names, atomic 

 sulphur and diatomic sulphur. It is very good for red spider and mites. 



PYRETHRUM 



This is commonly known as Persian or Dalmatian insect powder, or 

 Buhach, and comes as a finely ground yellow powder with a pleasant, 

 rather pungent odor. It is a contact poison and most larvae and soft- 

 bodied insects are thrown into convulsions when they come under its 

 influence. Unfortunately it is not only expensive but quickly loses its 

 effectiveness when exposed to the air. Its practical range is therefore 

 limited, and it is chiefly used on house plants, in the conservatory and 

 in the garden. It is entirely harmless to vegetation of all kinds and 

 does not spot or mark even the most delicate flowers when used dry. 

 It acts a little more promptly and effectively if applied to the insects 

 while they are moist, or at least damp. If the dusty appearance is 

 objectionable, a decoction may be made by steeping one ounce in one 

 quart of boiling water, and then adding two or three quarts of cold 

 water. Into this material potted plants may be dipped, or it may be 

 applied with an atomizer. For plant lice on house plants this makes 

 a very clean and effective application. 



HELLEBORE 



Powdered white hellebore has been used for many years as a specific 

 remedy against "currant worms," "rose slugs" and other saw-fly 

 larva?, and is very effective, either dusted on as a powder, or in the 

 form of a decoction. Tn the field it is now quite generally replaced 

 by arsenate of lead or even Paris green, but in the garden it still 

 holds its own. When applied, it may be used pure, or it may be 

 mixed with two or three times its own weight of dust, cheap flour, 

 lime, or almost any other light, finely powdered material. When 

 used as a spray, steep one ounce in one quart of boiling water and 

 add another quart of cold water when ready to apply. 



It is also quite effective against certain root maggots, like those 

 affecting cabbage and cauliflower. For these it is used in the form 

 of a decoction, one ounce in one gallon of water and about half a pint 

 poured around an infested plant, from which the earth has been 

 drawn away to facilitate soaking directly around the plant. To be 

 effective, the material must be brought into direct contact with the 

 insects. Hence, it should be liberally used and applied before the 

 maggots get down too far, or into the plant too deeply. In the garden 

 its use is quite practical ; in the field it has not been found so satis- 

 factory. 



