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PRODUCTIVE FARMING 



This disease is prevented by spraying in early spring 

 before the buds swell, with lime-sulfur preparation. This 

 is repeated with a weaker solution just before the blossom 

 buds open, and again just after the petals of the blossoms 

 fall to the ground. 



Fia. 144. — Leaf-curl disease. Healthy twig on right, the disease prevented by 



lime-sulfur spray. (Experiment Station, N. J.) 



Exercise. — Studying Apple Scab. — Have some one bring 

 to school a few samples of scabby apples from the grocery 

 store or home orchard. The class should all become familiar 

 with the ways in which the fruit is affected by the scab. 



Apple Rust. — Leaves attacked by apple rust appear as 

 though covered in blotches by a heavy coat of iron rust. 

 The whole under surface may present a rusty appearance 

 (Fig. 147). The trouble may spread to tender twigs and 



