when one is looking for it. Dr. H. Johannes * recently reported a 
very similar disease attributed to a species of Septogloem in 
Germany, except that some of the symptoms are different. The im- 
perfect stage of the Septotinia reported by Waterman and Cash ** 
was first described as Septogloem. In Germany, the disease, or a 
combination of diseases, is reported as killing the parent stocks 
and cuttings to a serious extent in the Helmstedt district of 
Brunswick. The Septotinia leaf blotch in the United States, and as 
noted in Holland, is primarily a leaf disease and so far has not 
been observed as causing any material loss. How it may develop 
under different conditions and on different hosts remains to be seen. 
61. The disease caused by Dothichiza populea is serious at 
times on some poplar species and hybrids both in Europe and North 
America. It is especially prevalent in the United States as die- 
back of the very common Lombardy poplar, P. nigra italica, and in 
some localities seems to be the primary factor in reducing the 
normal life cycle of these trees to a mere 15 or 20 years. 
62. The leaf spot and canker caused by the fungus Septoria 
musiva*** in North America has not been reported in Europe. I 
expect it has been introduced into Europe, as thousands of cuttings 
from infected stands have been shipped to Europe and requests 
from Europe for more cuttings continue to come to this country. 
Our quarantine inspectors carefully examine all cuttings before 
they are shipped, but no one can detect incipient cankers caused by 
fungi and bacteria, As this Septoria disease is so destructive to 
some poplar species and hybrids, and has not yet been reported as 
having become established in Europe, a definite inspection for this 
specific disease should be made of all poplar plantings grown from 
imported cuttings from the United States, Canada, and Argentina. 
If there are only a few infections of this disease established in 
Europe, it may be possible to eradicate it. 
63. Another serious poplar disease of North America, which has 
not been reported from Europe, is the canker caused by Hypoxylon 
pruinatum on aspens. 
© Johannes, H. Ein Pappelsterben, hervorgerufen durch den Pilz Septo- 
gloeum populiperdum sp. n. Nachrbl. dtsch. Pflsch. Dienst (Braunschw.) 
2,5, pp. 67-69, 3 figs., 1950 /Rev. Appl. Mycol. 30 (1) : 5-6, Jan. 19517 
** Waterman, Alma M.,and Edith K.Cash. Leaf blotch of poplar caused by 
a new species of Septotinia. Mycologia XLII (3) : 374-384. May-June, 1950. 
*** Waterman, Alma M., Canker of hybrid poplar clones in the United 
States, caused by Septoria musiva. Phytopath. 36 (2) : 148-156. Feb. 1946. 
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