854 EXPERIMENT STATION EECOED. 



necessary, and by early and free use of such fungicides as sulphur, polysulphids, 

 and permanganate of potash ^vith a view to prevention rather than cure. 



A root disease of the Para rubber tree (Fomes semitostus), K. Bancroft 

 (Dept. Agr. Fed. Malay States Bui. 13, 1912, pp. 30, pis. 79).— This is a brief 

 discussion of the history, distribution, spread, symptoms, and treatment of the 

 root disease of Ilevea brasiUensis and of its relation to other hosts and to 

 attacks by insects. 



The disease attacks the roots, cutting off the water supply, yellowing and 

 wilting the leaves, and killing the trees in from 4 months to 2 years according 

 to age. The fungus seems to propagate itself mainly by means of mycelium 

 which spreads in the roots, living or dead, also to some extent in the soil, 

 attacking live roots of young or old trees, but soon disappearing if left without 

 its customary substratum. 



Moisture, abundance of vegetable matter, acidity of soil, and darkness favor 

 mycelial growth. Experiments with artificial infections by means of mycelium 

 were successful in 10 out of 14 plants tried. Infection of living plants from 

 dead roots is thought to be the usual mode of transmission. Spores arise from 

 two forms of fructification, but are not known to carry the disease. Several 

 other hosts are known, all being woody plants. 



Methods of treatment include isolation by means of trenches; sanitation by 

 removal or burning in place of all infected or suspected trees or parts ; applica- 

 tion of lime to neutralize acidity, and possibly as a fungicide: drainage; and 

 utilization of the space with immune trees, while the infected roots of the 

 removed trees are disappearing from the soil, 



A brief bibliography is appended. 



Two new diseases of Sophora japonica, M. Tubconi and L. Maffei {Atti R. 

 Accad. Lincei, Rend. CI. Sci. Lis., Mat. e Nat., 5. ser., 21 {1912), II, No. Jf, 

 pp. 2^6-249). — This is a preliminary note descriptive of two new fungi, which 

 have received the names Macrosporiiwi sophorw and Gihberella hriosiana, at- 

 tacking, respectively, leaves and branches of the pagoda tree of China and 

 Japan. 



A case of g'ummosis in teak, J. A. Honing (Meded. DelirProefstat. Medan, 

 7 (1912), No. 1, pp. 12-15, 59). — An account is given of the evident infection 

 of teak nursery stock with Bacillus solanacearuni, causing gummosis, this 

 being claimed to be the first instance in which this plant has been attacked 

 by this disease. 



Macrophoma excelsa infestans parasitic on Abies concolor in Hussia, I. A. 

 Ohl {Zhnr. Boliezni Rast., 5 (1911), No. 5-S, pp. 121-13.'i, pi. 1, figs. 2; abs. in 

 Internat. Inst. Agr. [Rom,e'\, Bui. Bur. Agr. Intel, and Plant Diseases, 8 

 (1912), No. Jf, pp. 1067, 1068). — In Poltava A. concolor showed disease due to 

 a parasite identified as a Macrophoma, for which the author suggests the name 

 M. excelsa infestans. The use of fungicides in spring, and burning and removal 

 in autmnn, are remedial measures recommended. 



Lophodermium nervisequum. parasitic on fir needles, E. Mer (BuI. Soc. Nat. 

 Agr. France, 72 (1912), No. 7, pp. 615-625; Rev. Eaux et Fdrets, 51 (1912), 

 No. 16, pp. Ji81-Jf93, pi. 1). — Pursuant to studies previously noted (E. S. R., 25, 

 p. 47; 26, p. 451) with L. macrospornm on spruce, the author reports his in- 

 vestigations with L. nervisequum, parasitic on fir, which it is said to attack 

 when meeting it in a state of deficient nutrition, and causing, as does L. macro- 

 sporum, considerable loss in France. Experiments seem to show the protective 

 value of keeping trees well nourished and vigorous. 



Root disease of pine, M. Mangin (Compt. Rend. Acad. Sci. [Paris^, 154 

 (1912), No. 23, pp. 1525-1528).— The author made a study of this disease, of 

 the fungus (Rhizina inflata) said to cause it, and of the effects of forest fires 



