180 REPORT OF THE BOTANIST OF THB 
APRICOT DISEASES. 
CoLuaR Ror.—The most destructive apricot disease which we 
have come across is a disease of the trunk which may be called 
collar rot or dying at the collar. A large apricot orchard at 
Sodus has been ruined by it. This orchard was planted in 1890 
with apricots budded on apricot stocks. In each subsequent 
season some of the trees have died, and the others have made a 
stunted growth. The dead trees were replaced by others budded 
on Prunus simoni stocks. Many of these also died and then 
trees on Prunus mariana stocks were tried with no better re- 
sults, and at the present time the orchard is practically worth- 
less, . 
We became acquainted with the orchard in 1899. In May of 
that year we made a careful examination of the affected trees 
and found the seat of the trouble.located just below the surface 
of the ground at the point where the bud was originally inserted, 
which is called the union or collar. For a distance of three or 
four inches above the union the bark was dead and. brown en- 
tirely around the trunk. On trees recently dead the injury 
never extended below the union and often there was a sharp 
line of demarcation between the living bark of the stock and the 
dead bark of the trunk; but on trees which had been dead for 
some time the bark of the stock also turned brown and it was 
not so plain that the trouble had started at the union. _ 
As a rule, the affected trees wilt rather suddenly some time in 
early summer after having put out their leaves in an apparently 
normal manner. The trouble is not confined to any particular 
part of the orchard; dead trees are intermingled with living ones. 
Only a few of the trees have made a fair growth. The majority 
of the living trees have gnarly, stunted branches bearing large 
and prominent lenticels which make the bark very rough to the 
touch. The lenticels somewhat resemble the Cytospora pycnidia 
discussed below. 
We are unable to account satisfactorily for this apricot 
trouble. Neither insects nor fungi seem to be the cause of it. 
