226 



ON THE CORSICAN FIR. 



the fluid circulating throughout the canals, sparing, however, 

 if prudent, such stems as promise to yield large and valuable 

 timber. 



Among the European conifers of the present time the Corsican 

 fir yields the largest amount of resinous fluid. The quantity 

 contained in a tree depends on the state of health it is in, on 

 the strength and warmth of the soil over wliich it grows, on the 

 amount of light it enjoys {i.e., the development of the crown), 

 and on the warmth of the climate; in southern lands more resin 

 per stem is won than in northern, more also when the crown 

 of the tree is fully exposed to the enlivening influence of the 

 sunlight. 



The following sketch is intended to show how this valuable 

 product may best be obtained : — 



About ten years before a wood is to be felled wounds are made 



in S2:)ring (fig. 1) close to the foot of 

 the trees, and as the resinous fluid is 

 chiefly in the sapwood, these must be 

 made partly into the latter. The wound 

 is deep and sliaped like a swallow's nest; 

 in it the fluid collects, and is thus pre- 

 vented from trickling down to the ground. 

 At the same time the bark of one-third 

 of the circumference of the tree is peeled 

 off to a height of 16 to 18 inches, the 

 workman here also cutting some distance 

 into the sapwood with a knife or hatchet. 

 To convey the viscous mass into the 

 swallow's-nest-like receptacle, a groove 

 is made on each side of the wound 

 sloping downwards towards the middle. 

 From the end of April onwards tlie resinous substance is 

 collected every two to three weeks, and each time fresh pieces 

 of the bark and sapwood in a sideward direction are removed, 

 until only one-third of the circumference has a covering of bark 

 at the end of the first summer. In autumn the resin, that has 

 oozed out after the regular time of collecting it, becomes more 

 or less oxidised, and consequently of less value; it is scraped 

 off with iron instruments in November. In the following years 

 the wound is annually increased 16 to 18 inches in height, and 

 grooves are made as previously. At the end of ten years (fig. 2) 

 the bark around two-thirds of the stem has then been removed 

 to the height of 13^ to 15 feet; the remaining strip of bark is 

 sufficient to keep the tree alive. 



A tree from 90 to 120 years of age can yield jjcr annum 5| to 

 10 lbs., i.e., during the ten years 55 to 100 lbs., of raw resin. 

 The amount of more valuable viscous resin obtained during the 



Fig.l. 



