PESTS AND DISEASES OF PLANTS 229 



TREATMENTS FOR PESTS AND DISEASES.* 

 Apples, Pears and Quinces. 



Aphis, Green. Apply lime-sulphur just before buds open, if orchard 

 has been badly infected in past years. Apply kerosene emulsion or 

 tobacco washes as soon as the insects make their first appearance. 



Aphis, Leaf-Curling. Lime-sulphur plus Black Leaf 40, one pound 

 to 100 gallons. Apply when the buds are beginning to open, pink 

 showing in a few blossoms; spray very thoroughly. 



Aphis, Woolly. Spray with kerosene emulsion or tobacco washes 

 whenever this pest appears above ground. Use at least 200 pounds 

 pressure. For underground forms remove soil until upper roots are 

 exposed at the base of the tree. Pour several gallons of tobacco wash 

 around crown and replace soil when it has soaked in. Repeat often. 



Bud Moth. Use lime-sulphur in winter, and before leaf buds 

 open and after blossoms fall. Repeat every ten days if necessary. 



Brown Apricot Scale. Apply kerosene or distillate emulsions just 

 as soon as the leaves fall. Applications should be made before 

 December 1st. 



Codling Moth. Apply lead arsenate just as soon as blossoms fall. 

 Continue to spray at intervals of ten days or two weeks throughout 

 the season (at least four times). 



Canker Worms. Apply lead arsenate when the worms first appear. 

 Spray as often as needed. Tanglefoot bands on the tree are very 

 effective in keeping the caterpillars from the trees. 



Tussock Moth. Spray in full bloom with zinc arsenite, six pounds 

 to 200 gallons, and follow in ten days with neutral lead arsenate, 

 fifteen pounds to 200 gallons. 



Greedy Scale. Apply lime-sulphur when trees are dormant. This 

 scale seldom needs treatment. 



Oyster Shell Scale. Apply lime-sulphur when trees are dormant. 



Pear Slug. Dust on Paris green or other arsenicals, hellebore 

 or Pyrethrum. 



San Jose Scale. Apply lime-sulphur when trees are dormant. 

 Repeat in spring. 



Thrips. Spray with distillate emulsion and tobacco when the 

 insect appears in the spring abundantly. 



Black Spot Canker. Apply Bordeaux mixture, the first and 

 fifteenth of November. 



Bitter Rot. Apply weaker Bordeaux at first appearance of rot. 

 Repeat every two weeks if needed. 



Moss 6r Lichens. Apply crude oil emulsion and lye when trees 

 are dormant. 



'Adapted from the writings of W. II. Yolck, Horticultural Commissioner, 

 Santa Cruz County. 



