348 EXPERIMENT STATION EECORD. 



Heat injuries to forest plants, E. Munch (Naturw. ZtscJir. Forst u. Landw., 

 11 (1913), No. 12, pp. 557-562, figs. 2). — In a preliminary statement of studies 

 regardiug the injurious effects of heat on young forest trees, descriptions and 

 illustrations are given of injuries to young beeches and pines, as noted in the 

 dry, hot summer of 1911. Fungi found in connection therewith are thought to 

 have played the part of saprophytes merely. Temperatures of from 50 to 55° C. 

 (122 to 131° F.) at the surface of sandy soil are said to have been common 

 during that time. It is thought that such temperatures may prove directly 

 fatal to young plants independently of their drying influence. Protection 

 against direct sunshine is said to prevent this sort of injury. Raw humus is 

 most favorable to heat injury and loose sand almost as much so, the latter 

 being found in one case to be 16° hotter than compact sand, on account of its 

 poor conductivity. 



Injury from air exclusion and overheating, C. von Tubeuf (Naturw. 

 Ztschr. Forst u. Landw., 12 (1914), Nos. 2, pp. 67-88, figs. 2; 4, pp. 161-169).— 

 Detailing methods pursued and results obtained in experiments continued for 

 two years with artificial or solar heat applied to the trunlcs or roots of Fraxintis 

 excelsior or F. americana, the author states that stems were usually injured or 

 killed by long exposure to 42° C. (107.6° F.). Exclusion of air by means of 

 paint, etc., seemed to exert less influence than did high temperature. 



More on heat injuries to forest plants, E. MtJNCH (Naturw. Ztschr. Forst 

 u. Landtc., 12 (1914), No. 4> PP- 169-188). — Following the two contributions 

 noted above, the author gives a fuller discussion of observations made on heat 

 transference by absorption, radiation, conduction, and convection in relation 

 to plants, also of such modifying factors as moisture, nature and state of the 

 soil, etc. The suggestion is made that in these studies more exact means be 

 employed to ascei*tain the temperature of the plant itself, as this is always 

 lower than that of the adjacent soil at the surface under such circumstances. 



Notes on diseases of trees in the southern Appalachians, II, A. H. Graves 

 (Phytopathology, 4 (1914), ^o- -'j PP- 5-10, pi. 1, fig. 1). — In continuation of an 

 account of diseases in the southern Appalachians (E. S. R., 29, p. 851), the 

 author gives brief descriptions of the more important fungus diseases observed 

 on the scrub pine (Pinus virginiana). 



The most prevalent diseases are said to be the burl caused by Cronartium 

 qtiercus, heart rot due to Tramctcs pini, and a leaf cast (GaUoicaya pini). A 

 second disease of the needles caused by Coleosporium inconspicuum is said to be 

 rather rare. Among other injuries to the pine trees a description is given of 

 the damage done by wind, ice, and snow, and unfavorable soil conditions. 



Notes on Peridermium from Pennsylvania, C. R. Orton and J. F. Adams 

 (Phytopathology, 4 (1914), No. 1, pp. 23-26, pi. 1). — From a recent study of 

 some Peridermiums occurring on various si>ecies of pine, the authors conclude 

 that the form associated with Cronartium comptonia; should be called P. coinp- 

 tonicB n. comb., that C. comandra; is the alternate stage of P. pyriforme, and 

 that the Coleosporium occurring on Aster and Solidago has for its aecidial stage 

 P. acicolum. In the course of the investigations P. acicolum was found on 

 Pinus pungcns in addition to the usual host species. 



Notes on the white pine blister nist, P. Spaxilding (Ais. in Phytopathology, 

 4 (1914), No. 1, pp. 41^ 42). — In continuation of a previous report on this blister 

 rust (E. S. R., 29, p. 554) the author gives an account of its occurrence on 

 white pine in New York, near where it was first reported (E. S. R., 18, p. 747), 

 and also in northern Vermont. In Vermont a large white pine tree fully 75 

 years old was found badly infected and a number of younger trees were also 

 diseased. The fungus has been definitely reported in Denmark as occurring 



