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STATE HORTICULTURAL SOCIETY. 



ment of Agriculture at Washington, D. C, that fruitgrowers may 

 acquaint themselves with this new and one of the worst of all orchard 

 pests, and be on the watch for it, ready to stamp it out on the first 

 appearance. 



Apparently, scales were introduced from California in 1886 or 1887 on a 

 lot of Kelsey plum trees imported by New Jersey nurserymen. From these 

 trees the scales spread to the other nursery stock until all the trees were 

 more or less infested by them. By 1889 or 1890 the nurserymen, entirely 

 unaware of the presence of the scale or the mischief it would do, began send- 

 ing the trees to purchasers, and most of the known colonies are traceable 

 to this New Jersey stock. From these facts we may infer that young trees 

 that have been transplanted six years or less are most likely to have 

 the scale on them, and every orchard and fruit tree that has been trans- 

 planted within that time should be carefully examined to see that it has 

 no scale of this kind. Nursery stock should also be carefully inspected 

 for the scale before transplanting; and, could we have state or district 

 quarantine regulations against this and similar nursery importations, we 

 would be far safer than conditions now permit. 



San Joe6 Scale,— Male adalt — greatly enlarged. 



The scales will be most commonly found on the bark of the trunk and 

 limbs, though the young travel to the fruit and leaves. When left to 

 themselves for a few seasons they will cover an entire tree so thickly that 

 the bark can rarely be seen, and the tree has an ashy gray appearance and, 

 upon a closer examination, resembles a scurfy deposit. This species of 

 scale can readily be told from the oyster-shell bark louse (see Fig. 9), 

 and in fact from all other scale insects on our deciduous fruit trees, by 

 being circular and with a dark or yellowish dot in the center. The scales 

 are from a twelfth to a sixteenth of an inch in diameter. They are flat, 

 fitting close to the bark, but can easily be scraped off with the finger nail 

 and, when numerous, a yellowish, oily liquid will appear, resulting from 



