New York AGRICULTURAL EXPERIMENT STATION. 193 
ORIGIN OF THE GENEVA OUTBREAK. 
It would be interesting to know the origin of the outbreak at 
Geneva, but from the data now in hand it is not possible to locate 
definitely the original source of infection. It is likely that the 
fungus was imported with pines rather than with currants or goose- 
berries, since it is perennial within the stems and branches of the 
pine, while on Ribes it is confined entirely to the leaves. The only 
white pines in the immediate vicinity of the diseased currant plana- 
tion are two small trees standing 125 feet to the west. These were 
purchased from a Geneva nursery and set eight years ago. From 
a careful examination of these trees made in November they ap- 
peared in thrifty condition without any indication of Peridermium. 
Nevertheless, they may be the source of infection, notwithstanding 
their seeming freedom from disease. Peridermium. strobi should be 
sought in April and May; by November it is difficult to recognize. 
The two trees just mentioned are the only white pines on the 
Station grounds; and there are no specimens of Pinus cembra, P. 
lambertiana, P. monticola or any other Pinus having leaves in clus- 
ters of five. The nearest other possible sources of infection are a 
12-feet-high Pinus strobus sixty rods east, an aged Pinus strobus 
about eighty rods north and a sixteen-year-old Pinus cembra the 
same distance to the southeast. There are several nurseries in the 
vicinity of Geneva and it may be that some one of them has im- 
ported diseased pine trees. The nearest nursery containing pines 
liable to the disease is about one-half mile west of the Experiment 
Station. It contains a block of Pinus cembra and some Pinus stro- 
bus imported from France. Here may be the source of infection. 
However, contradictory evidence is found in the fact that a planta- 
tion of red currants (Ribes rubrum) directly across the road from 
this nursery was practically free from Cronartium. A careful 
search revealed just one leaf affected with Cronartium ribicola, 
which was in the teleuto stage. Another plantation of red currants 
between the nursery and the Experiment Station was entirely free 
from Cronartium. In fact the single affected leaf above mentioned 
is the only instance in which the Cronartium has been found outside 
the Station grounds although the neighboring currant plantations 
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