ANNUAL REPORT, 1932 39 



Agricultural lime products 14 



Ashes, cotton hull and wood 15 



Complete fertilizers 20 



Fertilizer chemicals and unmixed fertilizing materials 22 



Insecticides and fungicides 3 



Manures 8 



Manufacturers' by-products 7 



Miscellaneous 11 



Peat products 19 



Soils 37 



Contact and cooperation with the Association of Official Agricultural Chemists 

 has been maintained as in the past, in so far as rulings of the State Administra- 

 tion and the resources of the Control Department would permit. 



Vegetation Pot Experiment with Phosphates. Season of 1932. (H. D. 



Haskins.) This experiment, comprising 101 pots in a study of the phosphoric 

 acid availability of 20 different sources of phosphoric acid, has not reached the 

 stage where positive conclusions are possible. 



DEPARTMENT OF FLORICULTURE 

 Clark L. Thayer in Charge 



Study of the Effect of Plant Nutrients on Carnations and Roses Under 

 Glass. (Harold E. White, Waltham.) Urea, Calurea, Cal-Nitro, and ammon- 

 ium sulfate, when used as the source of nitrogen on a 4-12-4 basis, produced an 

 average of 30 flowers per square foot of bench area, whereas sodium nitrate and 

 calcium nitrate produced 25 flowers per square foot. 



Where Calurea was used as a source of nitrogen in a 4-12-4 mixture, applied at 

 the rate of from 1 ton to 4 1/2 tons per acre, there was a decrease of split flowers 

 from 33 per cent to 5 per cent. This would tend to indicate that one means of 

 lessening the tendency of carnations to split is by increasing the rate of application 

 of fertilizers within certain limits. The production of carnation plants was 

 increased from 18 flowers to 31 per square foot by increasing the rate of application 

 of 4-12-4 from 1 ton to 4 1/2 tons per acre. Fertilizer applied at a higher rate 

 than this resulted in a decrease in production. Carnations apparently will stand 

 high application of fertilizers as long as the phosphorus and potash balance is 

 maintained. Plots receiving as high as 10 tons per acre of a 4-12-4 showed no 

 injury other than a reduction in production of flowers. The only exception was 

 in the case of sodium nitrate where applications above 1500 pounds per acre re- 

 sulted in a stunting of the plants, a reduction in the size of the flowers, and an 

 adhesion of the flower petals. The adhesion symptoms did not occur in any other 

 plots even though the rates of application were the same as for sodium nitrate; 

 neither did dwarfing of the plants appear where the other materials were used 

 in equivalent amounts. The soil reaction does not appear to be a factor where 

 adhesion results from the excessive application of sodium nitrate, since in no 

 case did the pH go above 7.0. The lowest pH, even where high applications of 

 ammonium sulfate were made, did not go below pH 5.0. There was no noticeable 

 efi'ect of source of nitrogen or rate of fertilizer application on the rooting of carna- 

 tion cuttings. Stem rot was present early in the season in the plots, but there 

 appeared to be no correlation between feeding and severity of this disease on 

 carnations. 



