254 SUCCESSFUL FRUIT CULTURE 



Black Rot (Sphaeropsis malorum) The dying of 

 the end branches of the apple and pear, and the dead 

 patches of bark also found on the large branches and 

 trunk, are caused by this disease. The injured parts are 

 nearly black in color and studded over with pustules or 

 bead-like projections in which the spores are borne. 

 It also attacks the fruit in large black masses or some- 

 times infests the entire apple. When attacked in the 

 young stage the fruit hangs on the trees until the 

 following season. 



Remedy Spraying as for the cedar apple fungus 

 is effective. 



Powdery Mildew (Podosphaera oxyacanthae) This 

 fungus attacks young apple seedlings in the nursery 

 in the early summer and often so checks their growth 

 that they cannot be budded, but is seldom injurious to 

 large trees. 



Remedy The dipping of the seedlings in the bor- 

 deaux mixture before they are planted and one or two 

 sprayings during the summer will generally prevent 

 any injury. Trees planted in good soil on high land in 

 full exposure to light and air, are less likely to be 

 attacked than those in low places or moist soil. 



FUNGOUS PESTS ATTACKING THE PEAR 



The Apple Scab and Apple Rust, previously de- 

 scribed, are also injurious to the pear, but not to so 

 great a degree, and the remedies are the same. 



Leaf Blight or Leaf Spot (Entomosporium macu- 

 latum) This appears first as minute red dots that 

 increase to from one-sixteenth to one-eighth of an inch, 

 in diameter, and when in large numbers cause the leaves 

 to fall off in the middle of the summer, seriously 

 weakening the tree, or if the fruit is attacked, causing 

 it to crack. Sometimes a second set of leaves comes 

 out late in the summer, or even blossoms appear, and 



