ANNUAL REPORT, 1939 69 



Animal tissues for mineral poisons 4 Miscellaneous 8 



Fertilizer chemicals 10 Peat products U 



Industrial by products 6 Poultry manure 6 



Lime products 6 Soils 3 



Lime-sulfur 1 Wood ashes 2 



Mixed fertilizers 27* 



Total . 



♦Includes 15 private mixtures officially sampled. 



DEPARTMENT OF FLORICULTURE 

 Clark L. Thayer in Charge 



Breeding Snapdragons for Varietal Improvement and Disease Resistance. 



(Harold E. White, Waltham.) Field tests for rust reaction and selection of the 

 most promising Field Station strains are being continued. The yellow-flowered 

 lines set seed more readily and abundantly than the white- or pink-flowered 

 strains, and for this reason it has been possible to make a greater number of 

 individual selections of yellow forms. The pink-flowered strains, in addition to 

 being slow growing, are difficult types to true up as to exact shades of color. 

 Pure white flowers, even after continued selection, have a tendency to show a 

 touch of yellow in the palate of the flower. The stem length in most of the strains 

 is satisfactory but further improvement is needed in the size of the individual 

 florets and the length of flower spike. No indication of inherited resistance to 

 the wilt disease has been observed in commercial varieties or in the Field Station 

 strains. 



Effect of Plant Nutrients, Soil Reaction, and Light on Gardenias. (Harold 

 E. White, Waltham.) Gardenia plants fed with the same fertilizer mixtures from 

 year to year have varied in their response to such treatments, the number of 

 flowers produced and buds dropped varying according to the fertilizer treatment 

 and seasonal conditions. 



Over a period of three years less bud drop was noted with organic materials 

 than with fertilizers carrying ammonium or nitrate salts. Seasonal conditions, 

 however, appeared to have a greater bearing in determining the degree of loss 

 than did the fertilizer treatment. Flower production seemed to be influenced 

 by the same factors which determine bud drop. Gardenia plants did not appear 

 to grow any better in cinders than in soil. 



Species of Gardenia plants, grown from seeds obtained from South Africa, 

 seem to be less sensitive than commercial varieties to soil conditions which cause 

 symptoms of iron chlorosis. The species on which observations have been made 

 are: rothmannia, globosa, thunbergia, jovis-tonantis and radicans. The varieties 

 Belmont, Hadley, Mystery, Veitchi and the species florida show susceptibility 

 to iron deficiency. 



Forcing Tests of Hybrid Easter Lily Seedlings. (Harold E. White, Waltham.) 

 One hundred bulbs of hybrid lily seedlings grown in Charleston, South Carolina, 

 were received from the United States Horticultural Station at Beltsville, Mary- 

 land, for greenhouse forcing tests. The performance of the majority of the seed- 

 lings, as regards time required for forcing, number of blooms produced per plant, 

 size and texture of blooms, was comparable with results one might expect to get 

 from bulbs imported from Japan. The results of these tests with American- 

 grown seedling lily bulbs would indicate that the production of such bulbs for 

 greenhouse forcing may become a new horticultural enterprise in this country. 



