4 FLOUE PASTE AS A CONTROL FOR RED SPIDERS. 



although the sohition was effective against soine verj^ delicate species 

 and the younger stages of the hop aphis, it was not effective against 

 the stouter aphides. 



When the paste was dry the mites and more delicate aphides 

 treated were found firmly pasted onto the leaves. Later the paste 

 film was observed to crack and partially scale off, leaving the leaf 

 free to perform its natural functions. 



The neutrality of this spray was proved by the fact that when 

 applied upon the foliage and blossoms of the hop in proportions as 

 high as 12 pounds to 100 gallons no injurious effect resulted. 

 When sprayed onto the burrs and delicate hop cones it did not pre- 

 vent pollination or injure the appearance of the scales. 



Flour paste has proved effective when applied for red spiders upon 

 tlie following plants : 



Beans. 



Clirysantlieuiuin ( niny spot leaves if 



used too near blossom inj: time). 

 Hops. 

 Cucnmbev. jireenhonse and tieUL 



Pumpkin. 



Pear. 



Prune. 



Roses in field. 



Violets, field and greenhouse. 



The flour paste was not satisfactory when used for the red spider 

 on greenhouse roses (did not spread well), greenhouse carnations, or 

 field sweet peas. 



PREPARATION OF PASTE. 



To prepare the flour paste, mix a cheap grade of wheat flour with 

 cold water, making a thin batter, without lumps; or wash the flour 

 through a wire screen with a stream of cold water. Dilute until there 

 is 1 pound of flour in each gallon of mixture. Cook until a paste is 

 formed, stirring constantly to prevent caking or burning. Add suffi- 

 cient water to make up for evaporation. 



Flour paste may also be prepared by stirring boiling water into 

 a moderately thin batter until there is 1 pound of flour in each 

 gallon of mixture and allowing it to stand until the starch is all 

 broken down. 



If the paste is not sufficiently cooked, the residting spray will not 

 be effective, and if overcooked the paste will harden when thor- 

 oughly cool, and will not mix with water very readily. Usually, 

 however, the paste is used as it is prepared, and overcooking is not 

 a disadvantage. 



When mixed in the spray tank flour paste has a tendency to settle, 

 and in order to do satisfactory work agitation is necessary. This 

 is but a slight disadvantage, and is necessary with most materials. 



Flour paste appears to be a very effective sjDreader for lime-sul- 

 phur and nicotine-sulphate sprays. Cheap flour can be purchased 



