51

C—3a,

General Topography. —Type: Plateau. Drainage: Good. Exposure : Fairly exposed. Prevailing wind : South-west. Soil. —Formation : Rhyolite rock underlying. Soil : Pumice with light loam. Drainage : Good. Climate. —Rain : About 60 in. per annum. Climate : Mild in summer, cold and bleak in winter. Unseasonable frosts. Stand. —Type : Rimu-tawa type. Composition : 80 per cent, rimu and tawa, rimu varying from 50 to 30 per cent., and tawa from 30 to 50 per cent., with associated species including miro, matai, rata, rewarewa, hinau, and beech comprising the remaining 20 per cent. Density : Total merchantable stand about 12,500 ft. board measure per acre. Origin: Probably rich in taxads. Diameter development : Only few rimu-trees per acre with average diameter breast-high of about 40 in. ; tawatrees are more numerous, but merchantable specimens average only about 20 in. diameter breast-high. Regeneration : Rimu poor, tawa good. Insignis-pine Pulping Timbeb. Swanson, December, 1927. Locality. —Section 14 and south part old Swanson Kauri-gum Reserve (Birdwood Settlement), Block XIII, Waitemata S.D., Auckland Forest Conservation Region. Situation and Altitude. —Situation : One to two miles from Swanson Railway-station ; nine miles west of Auckland City. Altitude: 150 ft. Boundaries and, Area. —Small stand. 1J acres, and scattered trees. General Topography. —Rolling foothills of Waitakere Range. Drainage : Good to creeks, thence to upper Waitemata Harbour. Slope : Gentle to medium. Aspect: Westerly. Exposure: Moderately sheltered by hills. Prevailing winds : Westerly. Soil. —-Clay. Climate. —Rain : About 45 in. per annum. Climate : Mild. Forest-floor,— Litter : Pine-needles, 3 in. Humus : Fresh, shallow. Ground floor : Nil in plantation, grass and fern under scattered trees. Underbrush : Nil in plantation, manuka under scattered trees. Reproduction : Nil in plantation, manuka fairly plentiful in adjacent scrub and fern. Stand. —Type : Insignis pine, large poles and tall trees. Composition : Plantation pure insignis ; some P. pinaster with scattered trees. Origin : Plantation planted about thirty years ago ; remainder self-sown. Density of crown cover (plantation) : 95 per cent. Age : Plantation, thirty years ; scattered trees, twelve to eighteen years. Diameter development : Plantation average, D.8.H., 18 in. ; suppressed trees felled, 9 in. ; scattered trees —average 11 in., one tree 24 in. Height development: Plantation average height, 90 ft. ; suppressed trees felled, 60 ft. ; scattered trees —average 50 ft., one tree 70 ft. Form of trees : Good trees tall, with little taper and small lateral branches. Condition : Dominant and co-dominant trees vigorous, one or two scattered trees fire-scorched, but only living trees were felled. History of stand : Plantation planted about 1897 ; this was the first thinning ; scattered trees self-sown from adjacent pines. Merchantable condition of trees : Merchantable for sawing into box-timber, but owner of plantation is holding for a few years. Site class : 1. APPENDIX IL—METHODS USED IN THE CHEMICAL ANALYSIS OF WOODS AND PULPS. Sampling. The logs, as received, were sawn into 4 ft. lengths and peeled. Two of these 4 ft. logs were selected at random from each species, sawn into 1 ft. lengths, and quartered longitudinally. Two boards, approximately | in. thick, representing each part of the log, were cut lengthwise from these quarters in much the same manner as wood is quarter-sawn. These small boards were then reduced to sawdust by means of a special type of circular saw, previously described by Schorger.* The sawdust was quartered and ground to pass a 60-mesh standard sieve. The portion remaining on an 80-mesh sieve was used for analysis ; that passing through the 80-mesh sieve was discarded. Cellulose. Cross and Bevanf in 1880 found that ligno-celluloses when treated first with dilute NaOH solution, then with chlorine gas and dilute sodium-sulphite solution, yielded a white product resembling cotton cellulose, Schorger* showed that higher yields of cellulose were obtained by omitting the initial treatment of the wood with 1 per cent, sodium-hydroxide solution. In both the above methods the chlorination treatments are long, ranging from thirty minutes for the first chlorination to fifteen minutes for the last. Ritterf has shown that these chlorination periods may be shortened to three minutes for the first chlorination, and that even in this short period the same quantities of lignin and substances other than cellulose are removed. The cellulose thus isolated is in as pure a form as when treated with chlorine gas for the longer periods. Roe§ has described a method for the determination of the amount of chlorine absorbed by unbleached sulphite pulps. Dorej| chlorinated his samples directly in the crucible, and devised a special apparatus for that purpose. By application of the principles of these latter methods to the modified methods of Schorger and of Ritter for cellulose

* A. W. Schorger. J. Ind. & Eng. Chcm., 9 No. 6, 556 (1917). f Cross and Sevan, J. Chem. Soc., 38, 666 a (1880); Chemical News, 42, 77-91 (1880); J. Chem. Soc, 55, 199 (1889). % G. J. Ritter, J. Ind. _ Eng. Chem., 16, 947 (Sept., 1924). § R. B. Roe, J. Ind. & Eng. Chem., 16, 8, 808 (1924). || W. H. Dore, J. Ind. & Eng. Chem., 12, 264 (1920).