4 BULLETIN 116, IT. S. DEPARTMENT OF AGRICULTURE. 
had its top entirely dead above that point. Numerous small branches 
were found on other trees in a similar condition. A number of other 
trees of the same age apparently have been killed in a similar way, 
as they have been dying for years and have had to be removed, one or 
two at a time. While it takes a long time for the destructiveness of 
this disease to reach its climax in any given locality, there can be no 
doubt that if it finally becomes established and generally distributed 
in our forests it will be the worst enemy the white pine has here, as is 
stated to be the case in certain European countries. 1 It has become 
so thoroughly established in Europe that there is no hope of eradi- 
cating it there, but there is yet time to suppress it here if the danger is 
once generally realized. Even with conditions as they are in Europe, 
one of the most prominent plant pathologists of Germany recom- 
mends the energetic fighting of this disease. 2 If such action is 
advisable in Europe, even more drastic action is certainly proper in 
this country. 
CAN THIS DISEASE WINTER OVER ON RIBES? 
Late in 1912 F. C. Stewart asked the writer to take part in a 
cooperative experiment to try to determine whether this disease can 
winter over on dormant Ribes stock and thus be carried from one 
place to another in stock which has previously been diseased. Two 
hundred 2-year-old Ribes nigrum plants which had been heavily 
rusted by Cronartium ribicola in the late summer and early fall of 1912 
were sent to the writer at Washington, D. C, about December 1. 
They were promptly heeled in out of doors until February 1, when, 
according to agreement, they were potted and brought into the 
.greenhouse. They started quickly and made a very vigorous growth. 
They were examined several times for the presence of Cronartium 
ribicola, but none was found. The experiment was concluded about 
May 20 because of the writer's absence after that date. Parallel 
tests were made at Geneva and Ithaca, N. Y., Lafayette, Ind., 
Amherst, Mass., and New Haven, Conn., 300 plants being used. 3 
The results were entirely negative. The evidence furnished by the 
i Bos, J. Ritzema. Phytopathologiseh laboratorium Willie Commelin Scholten. Verslag over de inlich- 
tingen gegeven in 1900. In Landbouwk. Tiidschr., jaar 9, p. 77. 1901. 
Fisher, W. R. Experimental plantations at Coopers Hill. In Quart. Jour. Forest., v. 3, no. 3, p. 229. 
1909. 
Fron, Georges. Nouvelles observations sur quelques maladies des jeunes plants de Coniferes. In Bui. 
Soc. Mycol. France, t. 27, no. 4, p. 476-481. 1911. 
Lind, Jens. Danish fungi as represented in the herbarium of E. Rostrup, p. 281-283. Copenhagen, 1913 
Neger, F. W. Die Nadelholzer ... p. 110-111. Leipzig, 1907. 
Somerville, W. Peridermium strobi, the blister of Weymouth pine. In Quart. Jour. Forest., v. 3, no. 3, 
p. 232-236. 1909. 
Watson, J. G. The Woburn forests. In Gard. Chron.,s. 3, v. 52, p. 422. 1912. 
2 Tubeuf , Carl von. tJber die Verbreitung von Baumkrankheiten beim Pflanzenhandel. In Mitt. Deut. 
Dendrol. Gesell., p. 156-163, 1904. 
3 Stewart, F. C, and Rankin, W. H. Can Cronartium ribicola overwinter on the currant? In Phyto- 
pathology, v. 4, no. 1, p. 43. 1914. 
