20 



Some growers of experience in growing asters have 



New vs. Old claimed tliat this disease steadily increases from 



Soil. year to year if asters be planted on the same 



ground, there being very little the first 3'ear. This 

 is not borne out by our experience or observations in regard to this 

 disease, though true in the case of some other troubles. Repeated 

 instances have occurred of severe outbreaks of the disease on new 

 land where asters had never been before, while on the other hand 

 numerous examples can be cited where on ground badly affected one 

 year very little of the disease appeared the next. Certainly no gen- 

 eral rule holds good in this respect. 



The question of the chemical constituents and fer- 



Chemical tility of the soil is naturally one of great importance 



Nature of the in this connection. On considering, however, the 



Soil. variety of soils upon which the disease occurs and 



its general distribution, there is little basis for sup- 

 posing the disease to be due to the presence or lack of any particu- 

 lar substance or substances. Quite extensive experiments have nev- 

 ertheless been made along this line, but with no result. As between 

 mere fertility and its absence no difference appears except in the 

 general size and development of the plants. The disease is equally 

 prevalent. In regard to particular elements of plant-food plots were 

 laid out in two successive seasons and various combinations of the 

 essential elements tested, together with the effect of lime, compari- 

 sons between barnyard manure and fertilizers, etc. etc. No impor- 

 tant differences appeared. Plots with no fertilizer, with lime, barn- 

 yard manure, and all the combinations tested showed the disease 

 practically alike. While more exact tests might have been made, 

 the entire absence of suggestive results showed plainly enough the 

 futility ot further work along this line. Application of fertilizer at 

 intervals through the seasor^was also tested, but with no effect. 



Note. — In the principal experiment on fertilizers nine plots 6x25 feet 

 were laid out, separated by 3 ft. paths, on a level, uniform piece of land of 

 good general fertility, where asters had been tlie previous year. To these 

 plots were applied: No. i, nothing ; No. 2, iJ^ lbs. Sodium Nitrate, li lbs. 

 Muriate of Potash, i-i lbs. Dissolved Bone-black, No. 3, 3 lbs. Sodium 

 Nitrate, applied at intervals throughout the season ; No. 4, 3 lbs. Muriate 

 of Potash, applied at intervals; No. 5, i lb. Sodium Nitrate, i lb. iMuriate 

 Potash, I lb. Dissolved Bone-black : No. 6, same as No. 2 but applied at 

 intervals: No. 7, same as No. 5 but applied at intervals: No. 8, same as 



