420 Cultivation of Trujflcs. 



money upon the plantation, and, instead of raising truffles, only 

 to make a small bog. 



All the above preparations are necessary for wood lands, and 

 for plantations in large gardens and English shrubberies ; but the 

 further filling up of the pit is different for each place. In woods, 

 the soil contains much vegetable matter ; but that is not enough, 

 especially when an artificial mixture of earths is undertaken. In 

 order to obtain a very nutritious vegetable earth, let pure cow- 

 dung be carried into heaps in the spring, and left to fall into 

 earth in the course of the summer. That is best which is col- 

 lected as fresh as possible on pastures and commons. That it 

 may not lose its nutritious matter through drought and heat, the 

 heaps must be made in a shady place, be turned from time to 

 time, and, in dry weather, be often moistened with cow's urine, or 

 with soft river water. This watering must not be so abundant 

 as to allow the dung to become lixiviated, in which case its 

 most valuable powers will be communicated to the ground 

 underneath. 



In autumn, when the leaves fall from the trees, the dung is 

 for the greatest part converted into earth. The fourth or fifth 

 part of this earth is to be added to the natural wood soil ; and of 

 fallen oak leaves, or, if these are not to be had, of fallen horn- 

 beam leaves, as much in bulk as half of the mixture amounts 

 to: the whole must then be carefully mixed together. The 

 pit is to be completely filled with the mixture, which is to be 

 covered with a layer of oak leaves, of from 4 in. to 6 in. thick. 

 A wood soil, with much vegetable earth from oak trees, requires 

 a smaller addition of oak leaves, than a soil that contains less of 

 it. The greatest is required by the mixture of one half or the 

 third part of natural wood earth with the before-mentioned fer- 

 ruginous calcareous marl. In this case, which often occurs, as 

 many leaves are added as the proportion of the calcareous earth 

 occupies in space ; and the pit, when filled, is covered over with 

 a thick layer of leaves. 



There is no fear of this cover of leaves being carried away by 

 the storms that prevail in autumn and winter, as the truffle 

 plantations are made in low situations, sheltered by trees, and 

 not exposed to a strong current of air. If, however, this were 

 not to be avoided, the scattering of the leaves may be prevented 

 by some earth taken from the mixture being spread over them, 

 or by small branches of oak being laid upon them, and secured 

 by stones. Such a cover of leaves is of great service to the 

 planting of truffles ; since by the moisture of the winter the 

 most efficacious matter is extracted from it, and communicated 

 to the soil beneath. For this reason, a new cover must be laid 

 upon it every autumn. Early in the following spring, the upper- 

 most layer, being exhausted by the air, is to be taken away; but 



