18 BULLETIN 1186, U. S. DEPARTMENT OF AGRICULTURE. 
it took some years for it to become sufficiently well established to 
attract much attention. The most effective control method, con- 
sisting of Ribes extermination in the neighborhood of white-pine 
plantations, has seldom been practiced. Popular opinion favors sav- 
ing the black currants rather than the exotic white pine, because 
the people have a greater appreciation of their native currants than 
of a foreign tree. 
SWEDEN. 
Among the earliest recommendations for control are those made by 
Prof. Jakob Eriksson in Sweden in 1890 (73). He informed the 
writer that the control of the fungus by the removal of the Ribes 
had not been undertaken in Sweden. For some years white pine 
had been grown in nurseries at Djurgarden, Stockholm, but its cul- 
tivation was stopped in 1897 because of the increasing loss from 
Cronartium ribicola. At least 50 per cent of the seedlings between 
the ages of 3 and 5 years became diseased. All such infected stock 
was pulled out and burned, and Professor Eriksson gave orders that 
no white pine from the nursery was to be shipped to other parts of 
the country. 
Black currants and gooseberries were grown near the white-pine 
beds, the former species showing severe infection annually. The 
significant feature is that the cultivation of white pine ceased, while 
that of Ribes continued. A few old trees planted in the park at 
Djurgarden early in the nineteenth century became infected in the 
crown and on the side limbs. These trees were carefully treated by 
removing the diseased limbs, so that to-day they still survive, al- 
though somewhat lacking in natural symmetry because of the prun- 
ing away of the infected branches. 
NORWAY. 
A Norwegian writer, Schgyen, in 1895 recommended growing the 
Ribes and pine apart from each other (39, p. 56). This advice was 
followed in 1904 by Director Saxelund, of the Norwegian forest 
service, who ordered that no more Pinus strobus should be planted 
in the Government nurseries at Sandnes."4 
DENMARK. 
Rostrup, in Denmark, 1889, issued a bulletin to the forest guards 
dealing with the dangerous tree diseases, in which he advised that 
Ribes and white pine should always be separated (35, p. 11). The 
only case of the removal of Ribes from the vicinity of a white-pine 
plantation in Europe was brought to the writer’s attention at Cor- 
selitz, Denmark. The plantation referred to was located near the 
cottage of a forest guard, and 20 years ago an order was issued that 
no Ribes should be grown in the cottage garden. On what authority 
the order was issued is not known, but it is believed to have come 
from Rostrup. The removal of the black currants effectively 
checked the spread of the rust, and to-day the trees are thrifty. In 
contrast to this, consider the appearance of the 34-year-old white- 
pine plantation suffering from severe crown infection shown in 
1 Oral information from Skogforvalter A. Jenssen, Stavanger, Norway. 
