REPORT OF THE COMMITTEE ON WHITE PINE BLISTER RUST 651 



taxonomical Committees at the 11th International Botanical Congress, that 

 convened August 25-29 in Seattle, Washington. 2 



Dr. E. L. Little, Jr., kindly sent sufficient copies of the Critchfield 

 and Little paper so that each Committee member could have a personal copy. 



The accepted white pine taxonomy, with notes on synonomy, common names, 

 botanical ranges and crossability of species is also given in Bingham's 

 first article in these proceedings. 



(2) The question of gene-centers for Cronartium ribicola, i.e., one 

 in Asia, and another in the European Alps possibly separated in the 

 Pleistocene by Eurasian glaciation, was discussed by Subcommittee 

 Chairman Gremmen. However, presently coverage of the literature and 

 herbaria remains scanty, so the question was tabled in view of John 

 Gremmen' s volunteering to investigate the matter further and report on it 

 again at a later date (possibly at the Gainesville, Floria, IUFRO 

 meetings in March 1971) . 



(3) The question of securing more meaningful white pine blister rust 

 resistance ratings for the world's white pines was discussed with the 

 opinion emerging that really sound ratings will have to await provision of 

 a much wider range of materials by Kriebel's Subcommittee, and a more 

 thorough, worldwide testing thereof. Meanwhile, Bingham's incomplete, 

 tentative rankings (first article, these proceedings) will serve. 



(4) Bingham, Zufa, and Patton agreed that Committee Members and 

 other cooperators should have complete access and use of materials already 

 sent elsewhere in the world by the three white pine blister rust resis- 

 tance programs carried on by the U.S. Forest Service, Intermountain Forest 

 and Range Experiment Station, the Ontario Department of Lands and Forests, 

 and the University of Wisconsin Department of Plant Pathology, at the 

 discretion of the testing agency. It was noted that exact data on origin 

 and value of the material should be sought using the originator's plant 

 material numbers. 



(5) A newly introduced item of business was also discussed and acted 

 upon. This concerned the preservation of better stands of two white pine 

 species or varieties, apparently being threatneed by conversion of natural 

 stands to other faster-growing conifers. The first of these species was 

 Pinus armandii in Taiwan, the second the central and southern Honshu taxon 

 of Japanese P. -parviflora (i.e., P. pentaphylla var. himekomatsu 3 or 



P. himekomatsu) . Because these germ plasm sources, especially the better 

 stands thereof, are likely to be valuable in breeding for white pine 

 blister rust resistance and for other purposes, Chairman Bingham was 

 directed to prepare brief recommendations to the Governmental and other 

 agencies concerned, asking for preservation of at least a few better 

 stands of each taxon. S. K. Hyun prepared a skeleton recommendation and 

 provided addresses of Taiwanese officials to be contacted in respect to 

 P. armandii, and H. Saho prepared and provided similar materials for the 

 central Honshu taxon of P. parviflora. The Chairman will now contact 

 agencies involved to determine what, if any, steps are now contemplated 

 to preserve better stands of the two taxa and the extent f original and 



2 Editor's note: It is now (January 1971) known that the Standing 

 Committee on Stabilization did not act on the Committee on White Pine 

 Blister Rust recommendation during the Seattle Botanical Congress. 

 However, action is imminent 3 teste Dr. E. L. Little s Jr. 



