Influence of Mushrooms on Growth of Some Plants. 319 



The ash of the preparation contains iron, phosphoric acid and 

 sulphuric acid sahs in abundance. 



Judging from the results of Czapek's interesting studies in Hol- 

 meister's Beitrage zur chemischen Physiologic, i and ii, the high food 

 value of nutrient solutions such as the ones analyzed, would be at- 

 tributable to the relative richness in nitrogenous compounds of the non- 

 proteid type indicated in the analyses. Of course, his studies apply only 

 to such plants as can utilize organic nitrogenous compounds directly. In 

 the absence of information as to the character of the plants studied by 

 you, i. e., whether fungi or higher plants, etc., I cannot say whether such 

 a suggestion would apply. If you are working with the higher forms, it 

 may be that the final decomposition of the mushroom constituents is of 

 a type speedily resulting in the more available nitrogen compounds like 

 ammonia. At any rate your extracts soon pass into a stage where there 

 is relatively little nitrogen left in forms precipitable by tannic acid." 



The heating in sterilization of the un fermented mushroom probably 

 results in making some of the material available while the decomposition 

 products resulting from the fermentative decay of the mushroom furnish 

 a greater quantity of available ammonium compounds, sulphates, etc. It 

 would be interesting to know how extensive is the formation of am- 

 monium compounds, since these are directly available to corn and wheat 

 (and other Graminege), and in the forests where mushrooms are more 

 abundant, the nitrates are small in c[uantity, and forest trees and other 

 forest plants obtain most of their nitrogen in the form of ammonia com- 

 pounds.* 



The large quantity of sulphuric acid salts in the ash of the fer- 

 mented mushroom as well as in the ash (24.29 per cent) of the unfer- 

 mented mushroom, may account for the slightly poisonous effect on the 

 radish and cabbage plants in the pure cultures, and the still less poisonous 

 effect of the fermented mushroom on the corn and wheat in the sand 

 cultures. In the forest or field these injurious salts would quickly filter 

 away in the soil during rains and their injurious effect would probably 

 not be felt except in case of very large masses of decaying mushrooms. 



One reason why certain ammonium compounds are harmful to green 

 plants is due to the fact that they are strongly alkaline. The ammonia 

 nitrogen at the time of its formation during the ferment action of the 

 bacteria is probably alkaline. This may have caused the injury to the tips 

 of the roots of the corn, wheat, sunflower and buckwheat in the early 

 stage of growth of the seedlings when the fermentation was more active. 

 Later when the fermentation is less active, the corn and wheat in the 



*[ost, Vorlesungen iiber Pflanzenphysiologie, 163, 1904. 



