66 MASS. EXPERIMENT STATION BULLETIN 428 



In some flocks complications resulted from the fact that birds of an undesirable 

 age were inoculated. Also the condifion of the flock and the season of the year 

 had a definite influence on the results. The most satisfactory results are obtained 

 when the birds are 10 - 14 weeks of age, in good health, and inoculated on range 

 in June, July, and August when the weather is apt to be favorable. 



This control program is in need of many refinements. Work is in progress to 

 develop an immunizing procedure which will eliminate the possible hazard of 

 dissemination. 



5. Farm Department Brucellosis Control and Eradication. The laboratory 

 tested 369 bovine and ii porcine blood samples b}' the standard tube agglutina- 

 tion method during the 1944 calendar year. 



WALTHAM FIELD STATION 

 Waltham, Massachusetts 

 Ray M. Koon in Charge 



The members of the research staff of the Waltham Field Station are assigned 

 to this branch by the Departments of Botany, Entomology, Floriculture, Horti- 

 culture, and Vegetable Gardening. Refer to reports of these departments for 

 results of investigations conducted at this Station. 



Soil Testing Service. Commercial vegetable growers, mushroom growers, 

 florists, nurserymen, and vendors of loam brought in 2918 samples of soil for 

 testing and interpretation. For home gardeners, 3291 samples were tested. 



PUBLICATIONS 

 Bulletins 



417 Annual report for the period ending June 30, 1944. 78 pp. August 1944. 



The main purpose of this report is to provide an opportunity for pre- 

 senting in published form, recent results from experimentation in fields 

 or on projects where progress has not been such as to justify the general 

 and definite conclusions necessary to meet the requirements of bulletin 

 or journal. 



418 The propagation and identification of clonal rootstocks for the apple. By 



J. K. Shaw. 23 pp. illus. August 1944. 



There is a demand, far exceeding the supply, for clonal rootstocks for 

 growing dwarf and semi-dwarf apple trees. This bulletin tells how they 

 are grown and how the different kinds may be identified, thus helping to 

 keep these rootstocks true to name. 



419 Trellis tomatoes. By Robert E. Young. 19 pp. illus. November 1944. 



The tomato is one of the most important vegetable crops in Massachu- 

 setts, and the details of its culture are of significant economic interest. 

 This deals with the operation of a practice which has been growing in 

 favor. 



420 Mortality studies in Rhode Island Reds. By F. A. Hays. 20 pp. illus. 



November 1944. 



Mortality from all causes is one of the most important problems of 

 poultrymen. This report is intended to add something to the very limited 

 information on the role of breeding in reducing mortality. 



