No. 3, October, 1921] FORESTRY 197 



— light thinnings in youth, followed by heavier ones, — the basal area increases very little 

 after about the 100th year. The volume curves of 1920 at the 200-\'ear point are considerably 

 below those of 1905, due principally to the fact that a much greater volume is removed in 

 thinnings than was shown by tiie earlier curves. The total increment, including thinnings, 

 is not very different. The value-increment is probably considerably greater with the heavy 

 thinnings. The question as to the most effective kind and density of understory under the 

 oak is not yet answered. — W. N. Sparhawk. 



1271. Seeholzer. Die Naturverjiingung auf den Juraboden der Oberpfalz. [Natural 

 reproduction on the Jura of upper Palatinate.] Forstwiss. Centralbl. 43: 6-18. 1921. — In this 

 region, natural reproduction ismuch safer and more certain in producing a valuable stand than 

 artificial reproduction, either by seeding or planting. The climate is rather dry, periods of 

 drought are not uncommon, and the soil dries out and heats very quickly if exposed to the sun. 

 It is necessary, therefore, to use a silvicultural system which will conserve moisture and at 

 the same time prevent undue root competition between seedlings or between seedlings and old 

 trees. The system used must also favor abundant seed reproduction, must maintain the soil 

 in such condition that seeds will germinate and the seedlings establish themselves, and must 

 retain the mixed form of stand, — spruce with from 10 to 50 per cent of beech, fir, and pine, 

 according to local conditions. These requirements are best met by the selection system, 

 occasionally using the strip selection method, and being careful to keep openings rather 

 small. Cuttings should in most cases proceed regularly from the north side of the stand 

 toward the south, in order to conserve moisture. Since the application of the system varies 

 with each variation in local conditions, it requires a very intensive control by a trained 

 forester. — W. N . Sparhawk. 



1272. Sim, T. R. Timber trees for commercial culture. Further species that have been 

 tried in South Africa. South African Jour. Indust. 4: 161-165. 1921. 



1273. Sim, T. R. Tree planting for the farm. I. Selecting the site for the plantation. 

 South African Jour. Indust. 4: 218-223. 1921. 



1274. Skoien, Olaf. Antal aar paa sidste Cm. [The number of years' growth on the last 

 centimeter of radius.] Tidsskr. Skogbr. 28: 223-227. 1920. — Mistakes and errors which 

 result from the use of Schneider's formula are pointed out. Measurements on rapidly 

 growing trees will give a very short period as compared with the slower growing trees and 

 those on poor sites. Irregularities in the periodic growth are thereby overlooked and the 

 arithmetical means of the number of years in the last centimeter on the radius for trees in the 

 same diameter class introduce other errors. The use of the distance for each ten years' 

 growth overcomes these difficulties. — J. A. Larsen. 



1275. Stang, Thomas. Vest-Amerikanske traeslag for Norges Skogbruk. [West Ameri- 

 can trees for use in Norway.] Tidsskr. Skogbr. 28: 257-277. PI. 1-8., fig. 1-3. 1920. 



1276. Vanderyst, Hyac. Contributions a I'etude du palmier a huile au Congo beige: 

 5=. La recolte des produits de lElaeis. [Contributions to the study of the oil palm in Belgian 

 Congo: 5. The collection of the products of Elaeis.] Bull. Agric. Congo Beige 11: 22-36. Fig. 

 5-8. 1920. — Elaeis is one of the most useful trees of the Congo. The natives collect the sap, 

 w^hich by spontaneous fermentation is transformed into a more or less alcoholic drink known 

 as Malafu, or palm wine; the leaves are used for basket work and the fruits furnish oils of great 

 value. The methods employed by the natives in collecting these products are discussed, 

 and the danger incurred by them of contracting sleeping sickness. — E. M. Doidge. 



1277. Vaxderyst, Hyac. Contributions k letude du palmier a huile au Congo beige: 

 6=. Le tronc ou stipe de TElaeis. [Contributions to the study of the oil palm in Belgian Congo: 

 6. The trunk of Elaeis.] Bull. Agric. Congo Beige 11:37-53. Fig. 9-12. 1920.— In the neigh- 

 borhood of the mission at Leverville the trunk of Elaeis attains an average diameter of 33.6 



