July, 1909.] 



31 



7 imbers. 



and exceedingly twisted, thus making 

 the wood very difficult to split. 

 Mancono {Xanthostemon verdugonianus, 

 Naves.) 



The heartwood of Mancono is brown- 

 ish, turning purple when exposed to the 

 air ; the sapwood is very narrow, aud of 

 a pale reddish colour. The wood is very 

 heavy and hard, having a specific 

 gravity, after drying for ^ fifty-nine 

 hours at a temperature of 105° to 110 J 0. 

 of 1-236, equal to a weight of 77 pounds 

 per cubic foot.* The grain is fine and 

 twisted, and the fibres rather short and 

 exceedingly thickwalled. The hardness 

 of the wood is due mainly to the thick- 

 walled fibres, but partly also to deposits 

 in the vessels. 



Comparison of Mancono and. 

 Lignum vit^b. 



Botauically, these two species are not 

 closely related. In colour, the woods 

 differ materially. Lignum vitse also has 

 a resinous odour distinct from that of 

 Mancono. 



Sufficient tests have not been made to 

 allow of an accurate comparison as to 

 weight and hardness. Lignum vitse will 

 probably average a trifle heavier than 

 Mancono ; the Philippine species, how- 

 ever, being the harder. 



The grain of both woods is fine aud 

 twisted, but the West Indian species 

 has much the finer grain, and is there- 

 fore more difficult to split. In structure, 

 Lignum vitse differs from all known 

 woods in the weave of its fibres, which 

 are noticeably smaller than those of 

 Mancono. 



The seasoning qualities of Lignum 

 vitae are unknown. Mancono checks 

 badly upon exposure to the air, the 

 cracks, however, being superficial. 

 From the coarseness of the fibres, it is to 

 be expected that this species would 

 suffer somewhat in seasoning. 



Summarizing, it may be said that 

 Mancono is evidently inferior to Lignum 

 vitas in some respects, but that it has 

 enough good qualities to indicate that 

 it may be utilized, profitably, as a 

 subtitute. 



Distribution of Mancono. 

 Mancono, one of the important first- 

 group trees, is found in the southern 

 islands of the Philippine Archipelago, 

 commercial forests being restricted to 

 the coast Mils of the Surigao Peninsula, 

 and Dinagat, Bucas, and adjacent islands, 

 in the Provinces of Surigao aud Agusan, 

 Mindanao, P.I. As the tree has never 

 been extensively exploited the many 



* Tho weight of air-dry wood varies from 80 to 

 ■ 90 pounds per cubic foot, 



excellent qualities of the wood are but 

 little known to the general trade, though 

 the timber is highly prized by the 

 Filipinos of the south on account of its 

 durability and freedom from the attack 

 of white ants. 



A conservative estimate places the 

 total area of Mancono forest suitable for 

 logging, at 2,000 hectares (4*942 acres). 



DlSCRIPTION OF THE FOREST. 



On steep, rocky hillsides, rising sharp- 

 ly from the beach, it is usual to find 

 Mancono in almost pure stands, to the 

 practical exclusion of all other com- 

 mercial species. In such situations, 

 where the soil is a dry, compact, red- 

 dish clay, the tree attains maximum 

 development. 



From a distance, Mancono can be 

 easily distinguished by its rugged 

 branches, small leaves, and thin, spread- 

 ing crown. The tree flowers in May, 

 the blossoms being bright crimson in 

 colour. The bark of the tree is slate- 

 white, peeling in irregular flakes simillar 

 to the Sugar Gum (Eucalyptus curyno- 

 calyx) of Australia. It is very thin and 

 easily removed from the log after felling. 



The trees are rarely buttressed, but 

 the bole is irregular in shape, and tapers 

 rapidly. The maximum recorded dia- 

 meter, breast-high, is 115 centimeters 

 (45 inches), and the maximum clear 

 length 10 meters (33 feet). The average 

 clear length of fairly straight, mer- 

 chantable trees varies from 5 to 8 meters 

 (16 to 26 feet). It is estimated that 

 50 cent, of the trees measured on the 

 Island of Dinagat, Suriago Province, 

 had a trunk divided within 2 or 2' 5 

 meters (6£ or 8 feet) from the ground, 

 in many cases the fork occurring at a 

 distance of from 60 to 90 centimeters 

 (24 to 35 inches) above the base of the 

 tree. 



Table I, gives the average stand of 

 Mancono per hectare, and per acre, as 

 obtained from valuation surveys in a 

 practically pure stand. 



Table /.—Number of Trees per 

 Hectare, and per acre, of Mancono, 

 Dianagat Island, Province of 



Surgao, Mindanao. 

 [Average of 4 hectares (9'88 acres.)] 

 Diameter breast-high. ot 



Per Per Per 



Centimeters. Inches, hectare, acre, cent 



13 to 30 5 to 12 106-7 43'2 ) ' 



31 to 60 13 to 24 48-3 1EC5 J 80 

 61 to 90 25 to 35 20'0 



Over«90 Over 35 5"8 2-3j 14 



Total 



180-8 73-1 



100 



