374 
Journal of Agricultural Research 
Voi. XXVIII, No. 4 
The results presented above indicate some control of leather rot, though not 
such as would be considered satisfactory from a commercial point of view. It 
should be remembered, however, that they were obtained during an extremely 
wet season, in fields known to have suffered heavily from rot the previous year. 
It is planned to repeat these experiments another year. 
It is planned also to test the value of mulching as a means of preventing rot. 
Mulching is known to be good practice in other strawberry sections, and it proved 
to be quite effective during the season of 1923, in one field near Beebe, where it was 
tried out in a small way by a grower. The material used was pine needles, applied 
in such a way that when well settled they made a layer about an inch thick. The 
writer visited this field on several occasions, but failed each time to find rot of any 
kind in the mulched rows; in the unmulched rows alongside, leather rot and other 
rots were fully as common as in any of the unmulched fields in the Beebe district. 
No counts were made. 
The scarcity of leather rot in the district around Hammond, La., has 
already been referred to; attention has also been called to the fact that this dis¬ 
trict has as heavy rainfall as the strawberry districts farther north. But in the 
Hammond district practically all strawberry fields are mulched. In the writer’s 
opinion this is precisely the reason why the disease is so scarce there. It has been 
found, but only in a few unmulched or poorly mulched fields. 
SUMMARY 
1. A serious disease of strawberry fruits is reported which is apparently new 
to American phytopathological literature, though what seems to be the same 
disease was reported by Osterwalder (5) in 1912 as occurring in Switzerland. 
2 . It is demonstrated that the fungus, a Phytophthora, constantly asso¬ 
ciated with this disease is pathogenic to strawberry fruits. Evidence is pre¬ 
sented which indicates that this Phytophthora is identical with P. cactorum , first 
described by Lebert and Cohn and reported in the United States as parasitic on 
apples, pears, ginseng and rhubarb. 
3. The disease is described in detail and the common name of “leather rot” is 
suggested for it. 
4. It is demonstrated by this investigation that there is a close relation between 
leather rot and rainfall, and that in the region studied, the rot can be expected to 
reach a maximum within three to four days after heavy rains. Temperature is 
important also but its effect can not be determined without further study. 
LITERATURE CITED 
(1) Beach, W. S. 
1922. THE CROWN ROT OF RHUBARB CAUSED BY PHYTOPHTHORA CACTORUM. 
Pa. Agr. Exp. Sta. Bui. 174, 28 p., illus. 
(2) Bubak, F. 
1910. DIE PHYTOPHTHORAFAULE DER BIRNEN IN BOHMEN. Ztschr. Pflan- 
zenkrank. 20:256-261, illus. 
(3) Lafferty, H. A., and Pethybridge, G. H. 
1922. ON A PHYTOPHTHORA PARASITIC ON APPLES WHICH HAS BOTH AMPHI- 
GYNOUS AND PARAGYNOUS ANTHERIDIA; AND ON ALLIED SPECIES 
which show the same phenomenon. Sci. Proc. Roy. Dublin 
Soc. 17:29-43, illus. 
(4) Lebert, H., and Cohn, F. 
1875. ueber die faule der cactusstamme. Beitr. Biol. Pflanz. 1: 
51-57, illus. 
(5) Marchal, E. 
1908. sur une maladie nouvelle du poirier. Bui. Soc. Roy. Bot* 
Belgique 45: 343-344. 
