ANNUAL REPORT, 1944-45 43 



Effect of Dry Storajjc on 1 lylurjjopinus rufipcs Infestation of Elm Logs. (W. B. 



Becker.) At Amherst, winter-cut logs were piled in three (lr>' structures before 

 //. rufipes oviposition bcg-an in the spring. ThcvSe structures were two different 

 barns, the large doors of which were often open, and the basement of a building, 

 the small door of which was usually closed. The logs used were about 18 inches 

 long, between 2 and 8 inches in diameter, and had bark up to 3^ inch thick. 



Compared with the number of exit holes per square foot in logs piled outdoors 

 in the shade, 96.4 and 99.5 percent control resulted fnmi storing the logs in the 

 barns, and 99.6 percent from storing the logs in the basement. In addition to 

 the possibility of the beetles flying to the logs after they are stored, it must be 

 remembered that //. rufipes commonly spends the winter on the trunks of live 

 elm trees and so may be brought indoors on logs cut during that time. The dry- 

 ness indoors, of course, is unfavorable to the development of those beetles which 

 do become established in the logs. 



DEl^ARTMENT OF FLORICULTURE 

 Clark L. Thayer in Charge 



Breeding Snapdragons for Varietal Improvement and Disease Resistance. 



(1 larold K. White, Waltham.) The Field Station strains of snapdragons cojitinue 

 to show a high degree of resistance to rust disease in the field and greenhouse. 

 Thirty selections made of resistant lines yielded only seven showing rust, and 

 these showed relatively little rust, being from 10 to 25 percent susceptible. First- 

 generation hybrids of the rust-resi.stant strains have been much more vigorous 

 than inbred lines. These hybrid types cannot be used for seed production but 

 do give more uniform bloom, flower color, and plant growth. Since at present 

 this type of breeding is practiced on a limited scale with florist's crops, it offers 

 an interesting field of study. 



A large flowered, pink snapdragon developed from the I'ield Station strains 

 was named Helen Tobin, in honor of thj/ wife of the Governor of Massachusetts. 

 Res[)onsibility for distribution of seed of this new variety of winter-flowering 

 snai)(lragon has been assumed b>- the Northeastern Regional Unit of the Society 

 of American Florists. 



Disease Resistance and I leredity of Carnations. (Harold F. While, Waltham.) 

 Carnation seedling |)lanls ha\'e been sriecled from crosses juade between disease- 

 resistant and susceptible varieties of carnations. These plants arc to be tested 

 for disease resistance, and promising material will be used for further breeding. 

 Pollination work under glass in winter has not giviMi a satisfactory set of seed 

 on many crosses that have been attempted. 



Cultural Treatments of Anemone coronaria. (Ilamld K. White, W'aliliaju.) 

 Anemone tubers soaked 24 hours in warni water, or sprouted in sand in the 

 propagation house, grew much more ra])idly than tubers i)laiile(l (lr> in (lie soil. 

 I'lower production was greater on treated tubers than on untreated. 



Division of the tubers into too small units resulted in decreased (lower produc- 

 tion. Better flower production and more plant growth were obtained from ferti- 

 lizer containing nitrogen than from phosphate or potash alone. Anemones made 

 excellent growth and flowered as abundantly in gravel as in soil. 



Effect of Fungicidal Hormones on Carnation and Geranium Cuttings. (I larold 

 K. White, Waltham.) Cuttings of eight varieties of carnations treated with 

 Hormodin Power No. 1 and Stimroot powder showed no difference in degree of 



