Diseases of the Apricot. 209 
alkaline subsoil, the root shows it. Sometimes, however, a 
branch or a whole tree withers and dies without apparent cause 
early in the summer, and while the root is still sound. The dis- 
ease is evidently acute, but its cause is not known, nor a remedy 
proposed. It is an old trouble of the apricot, and not peculiar 
to California. 
The so-called “gum disease” sometimes causes injury to 
trees. The best treatment is to cut away the diseased part 
down to healthy wood and cover the wound with common lead 
and oil paint, put on sparingly so as not to flow over healthy 
bark. 
Some years certain varieties in particular are blackened at 
the pit and rendered unsalable, but the trouble has not thus tar 
proved serious generally, except with certain varieties which 
have generally gone out of use for that reason. 
The worst injury to tree and fruit is done by what is called 
the “shot-hole fungus” (Phyllosticta circumscissa), from its per- 
forations of the leaves as though by a charge from a shot- 
gun. It makes ugly scars on the fruit, which render it unsa- 
lable. The same disease also affects the leaves of cherries and 
plums. Thorough use of the Bordeaux mixture described in a 
later chapter will prevent this trouble. 
A disease which is prevalent in some districts of southern 
California is called “black heart;” a pit disease which sometimes 
does great injury. No treatment except that of pruning back 
to healthy wood has thus far been proposed. Root knot is also 
a serious trouble of the apricot, as of several other trees. It will 
be considered in the chapter devoted to diseases of fruit trees. 
Until recently the apricot has been generally free from 
scale insects, and it is not affected by those species which are 
worst on some other fruit trees, but recently it has been seri- 
ously infested in some places with black and brown scales, which 
will be considered in a later chapter. 
The ripe apricot is sometimes seriously assailed by the 
diabrotica, a small green beetle, with twelve black spots upon 
its wing covers. Driving the insects away with smoke smudges 
has been used to some extent. Fortunately, the insect only oc- 
casionally occurs in large numbers. 
VARIETIES OF THE APRICOT, 
Though nearly all standard varieties of the apricot have 
been introduced and planted in this State, comparatively few 
are found on the lists of the orchard planters. Many local 
seedlings have been brought to notice and propagated to some 
extent but are less used now than ten years ago, and the dis- 
position is to restrict planting to a few old varieties. There is, 
however, still a need of new varieties combining size, quality and 
