The Bulletin. 11 



fruits, peaches, plums, apples, pears, and cherries seem to be worst at- 

 tacked and die most readily in the order named. Certain varieties, 

 especially of pears, seem to show considerable resistance, the Keiffer, 

 Leconte, and Garber seeming to be less attacked than others, though by 

 no means exempt. Sour cherries are also resistant. 



Currants, Gooseberries, Roses, Grapes, Osage-orange, Thornapple, and 

 Japan Walnut are all quite subject to the San Jose Scale, though not so 

 readily attacked as the orchard fruits. Then there comes a long list of 

 other plants upon which it is of accidental or rare occurrence, such as 

 Persimmon, Walnut, Poplar, Chestnut, Sumac, Catalpa, Willow, Lin- 

 den, Ash, Dogwood, Elm, Maple, Strawberry, Easpberry, Milkweed, 

 Spruce, Cedar and even Crabgrass. But it must be remembered that its 

 occurrence on these last is unusual and as a rule they are not attacked, 

 even though they stand close to orchard trees that are badly infested. 



Forest and shade trees are very seldom infested with the San Jose 

 Scale, and are not appreciable factors in harboring or spreading infec- 

 tion. Growers sometimes make serious and ridiculous mistakes on this 

 point and give up hope because they imagine that the "scale is in the 

 woods," or they try to destroy the forests which they suspect, or spend 

 hours in a fruitless search for it on the forest or shade trees, and then, 

 when they find a scale (which is some other species in nine cases out of 

 ten) they think that they have surely found it. 



Let us repeat, then, with greater emphasis, that : the San Jose Scale is 

 primarily a pest of orchard fruit trees; it may also occur, but less fre- 

 quently, on rose, grape, currant, gooseberry, mochorange, and Japan 

 walnut, but forest and shade trees are not appreciable factors in harbor- 

 ing or spreading it. 



How Long Before It Kills the Tree?— The answer to this question 



will depend upon the kind of tree and the age at which it first becomes 

 infested. Let us take some different examples: 1. If the tree becomes 

 infested as soon as budded, peach and plum are likely to die within 

 from one to two years; apple, pear, and cherry in from two to four 

 years. 2. If they become infested when five years of age, peach and 

 plum will usually die in three or four years, pear in four or five years, 

 and cherry and apple in four to six years, or perhaps not at all. 3. If 

 they become infested at the age of eight years or over, our observation 

 has been that apples are not likely to be killed outright, though peaches, 

 plums, and pears may be. Of course, an infested tree should be regu- 

 larly and thoroughly treated whether it is going to be killed or not, for 

 otherwise it becomes a center from which the scale may spread to other 

 trees or orchards. Furthermore, though a tree may be too hardy to be 

 killed outright, yet the younger branches Avhere the fruit should be 

 borne may be injured to such an extent that the tree can not mature a 

 crop. 



The San Jose Scale in North Carolina.— A study of the map in 



Figure 3 shows that this pest is wide spread in this State, although thig 

 map was made up early in 1907. Hundreds of new cases have been 

 located since. Indeed at the present writing (April, 1912) the San 

 Jose Scale is on record in this office for seventy-seven counties and on the 



