THE GREENHEART OF COMMERCE 



289 



nate, but one rarely sees greenheart saplings from 2 to 

 4 inches in diameter in the virgin forest. 



Those who have hved among greenheart trees all their 

 lives, and who have watched them grow from year to 

 year have observed that the rate of growth of trees over 

 4 to 6 inches in diameter is exceedingly slow, and that 

 it varies according to the locality and soil. It grows 

 fastest in forests of deep, alluvial soil. Here the roots 

 can spread far and find more nourishment than in the 

 sandy clay region on the uplands. The rate of growth is 

 so slow that the annual rings on a transverse section of 

 a greenheart stem are not visible with a hand lens magni- 

 fying from 4 to G diameters, but from general observa- 

 tions it is known that even young trees on the hills and 

 drier slopes with soil or with rock near the surface, 

 grow very slowly. It is considered that at least 100 

 years are required for a greenheart tree to acquire a 

 merchantable size, and a good many of the large trees 

 that yield logs 24 inches square are doubtless over 300 

 years old. The period varies 

 much, however, in different 



regions of its range of growth 

 and also upon immediate en- 

 vironment of the individual trees. 

 Greenheart is known to occur 



in British, Dutch and French 



Guianas and in parts of eastern 



Venezuela. The reports that 



this tree is found in llrazil and 



in Colombia have not yet been 



authenticated, but it is quite 



likelv that it grows in Brazilian 



Guianas near the mouth of the 



Amazon. It grows chiefly on the 



moist slopes and ridges where 



the tops are exposed to the rays 



of the sun. On the dry, exposed 



ridges as well as in the wet soil 



along the rivers, it becomes 



scarce or disappears altogether. 



In the regions where it occurs 



most abundantly, the soil is a 



sandy clay, or, in some localities. 



almost pure sand and gravel. .\ 



stiff clay soil with a sufficient 



amount of sand to render it loose 



is favorable to its complete de- 

 velopment. In the lowlands 



where the soil consists of sand 



and loam, greenheart occurs less 



abundantly. 



In its habits greenheart may 



be considered to be partly gre- 

 garious, for although it always 



grows more or less intermixed 



with other trees, it is generally 



confined to certain areas of 



rather limited extent. It may 

 constitute the prevailing tree for 

 a few hundred vards. but seldom T''"'^ '^''s= '^""^ sates at 



for a mile continuously. Such localities are the moist 

 slopes that receive the moisture-laden air from the ocean, 

 and it is here where it attains its best development from 

 a commercial point of view. It is obvious that a tree 

 depending on so many local peculiarities cannot occur 

 continuously to any great extent. The Colonial Forest 

 Office of British (niiana determined by actual count that 

 on a sample area which contains greenheart in merchant- 

 able quantities, there were on an average about 150 tim- 

 ber trees to the acre, 32 of which were greenheart. 

 About 73 per cent of the greenheart trees were found 

 to range in circumference from 48 to ISO inches. Trees 

 which will not square 10 inches are not permitted under 

 the Crown Lands Regulations to be cut. 



The quantity of greenheart in British Guiana has been, 

 and still is, very great, although the lower forests have 

 been heavily worked, and now the best greenheart is 

 to be had only farther inland and in the less accessible 

 places above the cataracts in the rivers. This observation 



MAUK Ul- GKEEN HEART 



Wallsend on Tyne,' Knglatid. are made of greenheart timber imported from 

 Britisli Guiana especially for this purpose. 



