The Gardener and Practical Florist, 3: 236 (1844)

Charcoal and Willows

In the Forest of Dean I observed that the Charcoal "hearths or floors" soon became spontaneously covered with seedling willows, of a very vigorous growth. These seedlings made their appearance in about a year after the fires, and I do not recollect any other kind of seed germinating there except the willows. In this forest there is a kind of blue shale over the stratum of coal, this after being exposed to the atmosphere for some time crumbles down like shell marl. Mounds round some old coal-pits composed of this material were planted with oaks, which became the most vigorous of any in the forest, and were covered with healthy dark-green shining leaves. The coal shale is a valuable manure and would be useful to farmers, particularly upon light sandy heath and bog soils, and in localities where it abounds the proprietors of coal-works might profit by it. W. Billington, Oswestry, Salop. (Chronicle.)

[The greater portion of charcoal is made of willow, and, consequently, as it is lighter when manufactured than before it, the burning is generally conducted where the willow is cut, the probability is, that willow seeds abound in the earth, clearing the place, or the effect of so much charcoal, (which we know is favourable to vegetation) may cause the seeds in the ground to grow, but we will engage that any body may burn charcoal till their heart aches without making a willow grow where willows have never grown before, unless they sow the seed.]