458 EXPERIMENT STATION EECORD. 



sylv;mia, Indiana, and Ohio, and may be present in Minnesota and Ontario. It 

 Is Ivuowu to have been shipped to 230 different localities in North America, but 

 at the present time all known diseased stock has been destroyed. 



The gi-eatest damage done by the disease is in nurseries, where entire beds and 

 even the entire stock have been rendered unsalable. The following methods of 

 combating the disease are suggested : Import no five-leaf pine and Ilibes stock, 

 carefully inspect any imported Ribes stock during the first season and prefer- 

 ably during the second season also, keep five-leaf pines well separated from Ribes 

 stock if either is imported — at least 500 ft. apart — remove and burn all diseased 

 pine trees, inspect all pine stock from the last of April to June 10 and Ribes 

 stock from July 1 until late in the fall, and inspect diseased lots of pines the 

 second spring. 



A very extensive bibliography of some 250 titles is appended. 



The bladder rust of Scots pine, G. H. Pethybridge (Dept. Agr. and Tech. 

 Instr. Ireland Jour., 11 {Id 11), No. 3, pp. 500-502, pis. 2).— The author dis- 

 cusses the gross characters of this fungus (Peridermium pirn corticola), the 

 extent and character of the damage done by it, and its probable alternative 

 hosts. 



It is stated that many 40-year-old Scots pine trees are being killed by this 

 rust in Waterford County, Ireland. The alternate stages of the rust were 

 claimed by Liro (E. S. R.. 21, p. 321) to occur on certain species of the louse- 

 wort (Pedicular is palustrls and P. scoptrum carolinmn), and it is stated that 

 the rust should now be known as Cronartium peridermium pini. 



A new species of AJternaria, L. L. IIarter {Mycologia, 3 {1911), No. 3, 

 pp. 15J^, 155). — ^Attention is called to a leaf spot disease of Forsythia suspensa, 

 an ornamental shrub growing on the grounds of the United States Department 

 of Agriculture. Subcircular gray spots were develoiied irregularly over the 

 leaf surface and were surrounded by dead leaf tissue. 



The causative organism is claimed to be a new species of Alternaria, for 

 which the name of A. forsythiw is proposed. A technical description of the 

 fungus is appended. 



The fungicidal action of Bordeaux mixtures, B. T. P. Barker and C. T. 

 GiMiNGHAM {Jour. Agr. 8ci., 4 {1911), No. 1, pp. 76-94). — The authors dis- 

 cuss this under 3 heads, (1) the action of atmospheric agencies, (2) the action 

 of the host plant, and (3) the action of the fungus, and they give the results 

 of experiments on the action of the host and of the fungus on the spray. 



It was found that when the epidermal cells of the host were entirely sound 

 and unbroken, only an inappreciable amount of copper could be rendered 

 soluble by the host. In regard to the action of the fungi in rendering soluble 

 the copper present, it appeared that only very small quantities were thus made 

 soluble throughout the entire Bordeaux mixture film on the leaf, but that when 

 the spores or hyphse of several species of fungi were brought into direct contact 

 with the insoluble particles of the copper compounds death ensued, probably 

 due to a slight solvent action of the fungus on the particles. 



The authors, therefore, claim that the fungicidal effect of Bordeaux mixture 

 is not due to the absorption of atmospheric carbon dioxid by the spray, but is 

 caused by the spores or hyphte of the fungus coming into direct contact with the 

 insoluble particles of the copper compounds, thereby causing very minute quan- 

 tities of the copper to become soluble, and thus causing the death of the adja- 

 cent spores. 



The action of carbon dioxid on Bordeaux mixtures, C. T. Gimingham 

 (Jour. Agr. Sci., 4 {1911), No. 1, pp. 6D-75). — The results are given of experi- 

 ments on the influence of carbon dioxid on the basic copper sulphates in ren- 

 dering soluble the copper present in the mixtures. 



