248 EXPERIMENT STATION RECORD. [Vol. 43 



.ScTopli 111 aria cpii', mainly siiecies of Veronica, attacked by Prnmnsporn spp., 

 with developnienlal curves and descriptive accounts of the supitosedly new 

 species P. ai/restin, P. rcnui, P. arveusifi, P. puluntris, P. saxatilis, P. siliestris, 

 and P. aijnatka. 



The white pine hlister rust situation (Forest Leaves, 17 (lOl'J), No. 2, pp. 

 25, 26). — This contains a resuni6 of the report of the American Plant I'est Com- 

 mittee as previously noted (E. S. II., 41, p. SoO) and a summary j,'iven by 

 Metcalf (B. S. R., 41, pp. 352, 659) of the situation as existing at the time in 

 the United States and in Canada. 



White pine blister rust control in 1919, S. B. Detwiler {Amer. Plant 

 Pest Com. Bui. ^ [1919], pp. 1-3). — Tlie Fifth Annual International Blister Rust 

 Conference was held at Albany, N. Y., December 8-9, 1919, under the auspices 

 of the American Plant Pest Committee (E. S. R., 41, pp. 350, 351). Foresters 

 and pathologists representing tlie New England States, New York, Pennsyl- 

 vania, Wisconsin, Minnesota, and Canada were present. 



In a summary of the report of this body it is stated that experiments con- 

 ducted on an extensive scale since 191G show that white pine blister rust can 

 be controlled locally by destroying wild and cultivated currant and gooseberry 

 bushes within a comparatively short distance of the pines, 200 to 300 yds. being 

 sufficient to prevent serious damage under average forest conditions. This 

 reduction of 50 per cent in the minimum width of the safety zone hitherto 

 reconnnended is ba.sed on four years' scientific and practical field studies. 



Unskilled laborers can be quickly taught to remove at least 95 per cent of 

 the wild currant and gooseberry bushes in going over the ground once. Wild 

 currants and gooseberries do not reproduce rapidly in an area that has been 

 worked by an efficient crew. Bushes missed by the crews are usually small 

 plants growing in undei"brusli, having less leaf surface than the average plant 

 and causing proportionately less damage. On lour control areas worked in 

 1916-17 no new pine infections could be found in 1919. The cost per area of 

 destroying these bushes has been considerably decreased. 



Blister rust infection on pines in the Northeastern States is increasing rapidly. 

 Timber owners in infected regions who permit currant and gooseberry bushes 

 to grow within 200 to 300 yds. of the wliite pine suffer severe loss. Cultivated 

 black currants are especially susceptible to blister ru.st, but all kinds will cause 

 sei'ious damages to pines. White pine blister rust has not been found in the 

 western half of the United States or in western Canada, where wild currants 

 and gooseberries are abundant. 



Resolutions adopted by the Fifth International Blister Rust Conference, 

 Albany, N. Y., December 8 and 9, 1919 {Amer. Plant Pest Com. Bui. 4 

 [1919\, pp. 4< 5). — The conference urgently reconmiends the complete destruc- 

 tion of all Ribes within 200 to 300 yds. of native and planted white pines in 

 regions where blister rust is present or dangerously near. The conference also 

 reconunends a vigorous campaign for planting white pine with proper precau- 

 tions against infection, estimating the value of 5-needled white pines in North 

 America in 1919 at $605,000,000. 



Summary by States and regions [of white pine blister rust work, 1919], 

 S. B. Detwilek (Amer. Plant Pest Com. Bui. 4 [1919], pp. 6-10).— A condensed 

 account is given on the same plan as that previou.sly noted (E. S. R.. 41, p. 351), 

 of work done and the situation existing in each of the New England States and 

 in New York, New Jersey, Pennsylvania, Maryland. Virginia, West Virginia, 

 Minnesota, Wisconsin, Michigan, and other States iu the Central West. The 

 Rocky Mountain and Pacific Coast regions seem to be clear of white pine blister 

 rust. Scouting has been continued in these regions since 1917. A Crouartium 



