66 MASS. EXPERIMENT STATION BULLETIN 339 



tion growers in Massachusetts. This type of experimental setup is worthy of 

 note inasmuch as most of the fertilizer experimental work reported by institu- 

 tions doing work in Floriculture has been conducted on small plots at the 

 stations on one particular soil type. This work was inaugurated by a research 

 committee composed of growers appointed by the New England Carnation 

 Growers' Association to work with the Experiment Station. 



The growers expressed an opinion that specific or general recommendations 

 as to fertilizer applications to carnation soils in Massachusetts can be made 

 more satisfactorily by conducting studies on their own soil types and under 

 commercial growing conditions, rather than on one soil type and with small 

 plots as at the Experiment Station. A total of 1800 square feet of bench space 

 of carnations is under observation in nine ranges of glass, with 200 square feet 

 of space being devoted to this purpose by each grower. The ranges chosen have 

 been selected with due regard to possible variation in weather conditions and 

 soil types. 



The work has not been in progress long enough to permit accumulation of 

 much data except results of physical and chemical analyses of field or compost 

 soils before any fertilizers were applied. 



The soil pH determinations were made with a potentiometer equipped with a 

 quinhydrone electrode. Tests for nutrient elements were made with the 

 Morgan micro-chemical or quick-test methods, with due care being given to 

 interpretation of the results. 



The micro-chemical tests for nutrient elements are accepted by many 

 workers as a means of determining the relative levels of reserve plant food 

 elements in soil on the basis of being adequate or inadequate for normal plant 

 growth. A possible explanation of the reason why many of the soils appear to 

 be uniform in content of nutrients while having no apparent similarity in 

 origin may be the fact that the tests were originally designed on the basis of 

 field soil fertility and not calibrated for the higher nutrient levels as they exist 

 under greenhouse conditions. That is, the maximum and minimum levels as 

 established by the tests for field conditions do not hold true for greenhouse soils. 

 These micro-chemical tests have been applied to the soils from the experimental 

 plots with the purpose of determining whether or not the system is suitable for 

 use under greenhouse conditions, and if so to establish approximate levels of 

 fertility on the basis of these tests. Soil productivity with regard to plant-food 

 elements can be evaluated only as potential reserves inasmuch as other environ- 

 mental conditions are limiting factors. 



Horticultural Schools. (Harold E. White, Waltham.) This year a de- 

 parture was made from our usual method of conducting the Home Gardeners' 

 School lectures by distributing the lectures through the month of April, instead 

 of having a two-day program. Each lecture was held in the afternoon from 1 :30 

 to 4:30. The reasons for this change were to allow more time for personal and 

 general questions on the topics discussed and to associate the program more 

 closely with the College by using our small meeting hall in place of the large hall 

 at Cedar Hill. The response to the program was more than satisfying in that 

 the registration was so great that it was necessary to repeat four of the seven 

 lectures, making a total of eleven lectures given. The registration surpassed 

 our 1931 record of 700 by increasing to 1166 for the series of 1936. 



There were 217 florists in attendance at the Florists' School held on February 

 18 and 19 at the Waltham Field Station. 



The registration figures and interest of the general public in these schools 

 indicate that they are worthy of the financial support given them by the College. 



