An Apricot Blight. 
By Wendell Paddock. 
The writer’s attention was called to a disease of apricots in 
the fall of 1902 by Mr. H. E. Mathews, horticultural inspector of 
Delta county, which was thought by the growers to be an attack 
of pear blight. Many of the twigs had blighted and all of the 
fruit on several of the trees had decayed. At the time of my 
visit it was too late in the season to see the disease in an active 
condition, but microscopic examination of the dead twigs and of 
the dried fruit failed to show any sign of fungous attack. The 
indications pointed to a bacterial disease but the idea that it was 
caused by the germs of pear blight was doubted since at that 
time there was no record of this disease ever having attacked the 
stone fruits. 
The orchard was visited again on June 25 , 1903 , when the 
disease was found in an active condition. In one row, containing 
ten Moorpark and ten Royal apricot trees, every tree was more or 
less affected, as well as other trees in various parts of the orchard. 
At this time many of the fruits were attacked, the diseased 
areas varying in size from a spot an eighth of an inch in diameter 
to irregular areas that involved three-fourths of the fruit. The 
skin over these places soon became nearly black in color and 
shrunken as the tissues were consumed till the outline of the pit 
was disclosed. These discolored areas were alwavs definitelv out- 
lined and bordered with a zone of watery appearing tissue usually 
about an eighth of an inch in width. The latter was green in 
color and as hard as the sound flesh. Three such fruits are shown 
on Plate I. 
The smaller spots where the disease had evidently just 
started, invariably surrounded a lenticle, thus indicating that the 
disease gained entrance to the fruit through these openings. 
- — The injury to the twigs may be described best by saying, 
that they resembled closely, blighting pear or apple twigs. (Plate 
II.) So far as noticed only tender twigs of the current season’s 
growth were attacked. These were shrivelled and discolored from 
a few to several inches of their length and small drops of sticky 
fluid were occasionally found on their surface and upon the 
