316 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIKTY. 



NOTES AND QUERIES, 



Forest Fires. 



The following notes, compiled from the translation of an article 

 by M. Jacquot in the Revue des EoAix et Forets, published in the 

 Indian Forester, will interest students of this question. 



Dead Leaves. 



M. Berthelot, and more fully MM. Gauthier and Drouin, have 

 proved that a fire, if sufficiently intense to decompose the humus 

 and humic acid, thereby destroys the faculty they possessed of 

 developing those most essential and scarce substances which 

 contain nitrogen. Even if the fire does not destroy woody tissues, 

 it burns up the covering of dead leaves. M. Ddtrie suspected 

 what M. Coudon and especially M. E. Grandeau have proved, viz., 

 that these dead leaves possess the precious faculty of ahsoi-hing 

 nitrogen from the air. Since MM, Schloesing and Miintz in 1877 

 discovered the nitromonad, the first bacterium whose powerful 

 action on the chemical changes in the soil was proved, attention 

 has been concentrated rather on its agricultural than on its forest 

 utility. The researches of M. Henry therefore mark an important 

 step in science. By his expei'iments in 1897 the learned professor 

 of the French Forest School proved that dead leaves may even 

 double their original richness. 



The quantity of leaves produced annually on 1 hectare varies 

 with the soil, climate, species, age, treatment, and density of the 

 crop and the luxuriance of the crowns. It may reach 12,000^ 

 kilogrammes of the living substance. The Bavarian stations have 

 supplied some valuable figures, but these, as M. Henry remarks, 

 are minima : " They relate indeed to forests afflicted with rights 

 to fodder. The impoverishment resulting from this detestable 

 practice reacts fatally on the vegetation." Other countries supply 

 similar proofs. Jaeger and Buro, working under the same 

 conditions, arrived at the same results as Professor Ebermayer. 

 But Dr Krutsch, examining soils that were not so impoverished,, 



^ Equivalent to nearly 11,000 lbs. per acre. 



