48 EXPERIMENT STATION RECORD. [Vol.41 



spruce consistent with hnnbering conditions and danger from windfall should 

 be left. It is concluded that possibly no satisfactory system of management 

 for spruce can be found short of clear cutting and planting. In the area 

 studied the spruce is being ci'owded out by the hardwoods which have taken 

 advantage of the openings and are spreading out over the unused spaces every 

 time that a conifer is removed. 



On the question of forest renewal, H. Beekman (Boschhouwlc. Tijdschr. 

 Tcctana, 12 (1919), No. 1-2, pp. 1-129). — An exposition on forest regeneration 

 in Netherlands Indies, with special reference to the reproduction of teak. An 

 outline is given of investigations dealing with forest renewal conducted at the 

 Forest Experiment Station, together with a bil)liography of cited literature. 



The northeastern Minnesota forest fires of October 12, 1918, H. W. Rich- 

 ardson {Gcogr. Rev., 7 {1919), No. 4, pp. 220-232, fujs. 5).— A historical record 

 of this disastrous flre, including a detailed map of the region burned over. 



A contribution on the tan bark question, van den Bussche (Boschbouxrk. 

 Tidjschr. Tectona, 12 {1919), No. 3, pp. 217-251). — A review of the present 

 status of the tan bark industry in Java, including suggestions relative to its 

 future development. 



Charcoal burning in Sweden, M. A. F. Dijkmans {Cnltura, SI {1919), No. 

 3G8, pp. 115-145, pis. 5, figs. 19). — A descriptive account of methods used in 

 producing charcoal in Sweden. 



DISEASES OF PLANTS. 



Plant disease investigations (Kansas Sta. Rpt. 1918, pp. S6-SS). — The prin- 

 cipal investigations in plant diseases carried on by the station were studies of 

 wheat stem rust and corn smut and the resistance of sorglmms to kernel smut. 



More than 150 varieties of winter wheat were tested ior their resistance to 

 the stem rust {Puccinia graminis tritici), the experiments being undertaken 

 both in the field and in the greenhouse. Three hard winter wheats were found 

 remarkably resistant to the stem rust. Various selections have been made of 

 these varieties, which are being propagated, as they appear to be of great 

 commercial value. Hybrids between some of these forms and some spring 

 wheats have been produced and the Fi generation grown to maturity. 



In connection with the rust investigations a biologic form was observed, 

 an account of which has already been given (E. S. R., 39, p. 454). 



In the smut investigations it was found that tlie smut organism is carried 

 from the soil by the wind to the axils of the corn plant, from which cultures 

 were readily obtained. A virulent culture in the topmost leaf axil was found 

 to be a source for infecting the several nodes below. In an attempt to con- 

 trol the corn smut by the use of Bordeaux mixture and formaldehyde spray*, 

 the treatments under Kansas conditions were found to be neither practical 

 nor effective. While the percentage of corn smut was in some cases reduced, 

 there was also a reduction in the yield. Some resistance to smut was reported 

 in case of certain varieties. 



A test was made of 38 varieties of sorghums to determine their resistance 

 to kernel smut, and infection was found to vary from per cent in case of 

 milo, feterita, White durra, and Brown kaoliang to 38 per cent in the sorgo 

 group. Attention is called to the fact that, while milo and feterita are usually 

 classed as immune to smut, experiments have shown that infection can be se- 

 cured by artificially injuring the .seed and dusting them with smut spores. 



Report of the department of plant pathology, M. T. Cook (New Jersey 

 Stas. Rpt. 1917, pp. 52S-5S5, pU. 5).— The author briefly refers to work that 



