FERNS, FENCES, AND WHITE BIRCHES 199 



You will find vast mats of these leathery little Poly- 

 podys growing with rock-selaginella on the great bould- 

 ers of the river woods. As these are to be split up for 

 masonry, the experiment of transferring the polypody is 

 no sin, though it savours somewhat of the process of 

 skin-grafting. Evan and I have tried the experiment 

 successfully, so that it is no fable. We had a bit of 

 shady bank at home that proved by the mosses that 

 grew on it that it was moistened from beneath the 

 year through. The protecting shade was of tall 

 hickories, and a rock ledge some twenty feet high 

 shielded it from the south and east. We scraped 

 the moss from a circle of about six feet and loosened 

 the surface of the earth only, and very carefully. 

 Then we spread some moist leaf-mould on the 

 rough but flat surface of a partly exposed rock. Going 

 to a near-by bit of woods that was being despoiled, as in 

 your valley, we chose two great mats of polypody and 

 moss that had no piercing twigs to break the fabric, 

 and carefully peeled them from the rocks, as you would 

 bark from a tree, the matted rootstocks weaving all 

 together. Moistening these thoroughly, we wrapped 

 them in a horse blanket and hurried home. The earth 

 and rock already prepared were sprinkled with water 

 and the fern fabric applied and gently but firmly pressed 



