June, 1920] FORESTRY 290 



2040. MAkn, L. Mattsson. Nagra synpunkter pa variations- och korrelations-ber&k- 

 ningar. Med anledning av Sven Petrinis undersbkning: "Form-punktsmetoden och dess an- 

 vandning for formklassbestamning och kubering." [Some views regarding mathematical varia- 

 tions and correlations, with reference to Sven Petrinis investigation: "The form-point method 

 and its use in determinations of form-class and volume. "J Skogsv&rdsforen. Tidskr. 17: 

 109-122. 1 fig. 1919. 



2041. Mkk, E. Influence de la dimension des arbres sur l'efncacite des eclaircies. 

 [Influence of size of trees on results of thinning.] Kev. Faux et Forets 57: 141—146, 165-175. 

 1919. — Two sample plots in a stand of fir about 60 years old and averaging respectively 9.3 

 and 11.2 cm. in diameter, were thinned in 1886 and again in 1899. Careful records of growth 

 which were maintained until 1911 showed that the increased growth resulting from the 

 thinnings was uniformly greater both in diameter and volume in the smaller trees. This 

 difference is probably due to the fact that the smaller trees were younger and therefore more 

 vigorous than the larger trees. While further investigation is needed to determine how 

 generally applicable are the results of this experiment, two conclusions may be drawn from 

 it, — (1) that sample plots to study the effect of different degrees of thinning should be com- 

 posed of trees of as nearly as possible the same size; (2) that as a rule thinnings may be profit- 

 ably undertaken at an earlier age than is now customary. — S. T. Dana. 



2042. Mongenot. L'epicea et la secheresse. [The spruce in relation to dryness.] Compt. 

 Rend. Acad. Agric. France 5 : 713-715. 1919. — discusses the relation of the spruce to the water 

 supply and shows how it is this factor that limits the altitude below which this tree cannot 

 be planted in the south of France, since the rainfall decreases as one descends. — E. A. 

 Bessey. 



2043. Myhrwold. Den svenske statsskogforvaltning aar 1917. [Review of the Swedish 

 government forest report for 1917.] Tidsskr. Skogbruk 27:202-208. 1919 —The total area 

 within designated forest land in Sweden is given at 22,398,195 hectares. Of this the Govern- 

 ment owns 6,070,230 hectares and maintains supervision over 2,640,704 hectares in the hands 

 of different state institutions. 3,757,109 hectares of the Government owned land is con- 

 sidered productive forest area. The Government maintains seven forest schools and one 

 forest school of higher training. The permanent and temporary personnel consist of 1556 

 men, all of whom have passed the required exams. 505 men make up the permanent force. 

 In 1917 the Government sold from its holdings, 4,189,694 cubic meters (m 3 ) of miscellaneous 

 forest products at a total receipt of 38,422,635 crowns. During the same year the sum total 

 of the expenditures amounted to 12,273,689 crowns. The net receipt was therefore in the 

 neighborhood of seven million dollars. Only 1.200 hectares burned over in 1917. (One 

 crown is about 28 cents, and one hectare is 2.47 acres.) — J. A. Larsen. 



2044. Xordstedt, C. T. O. [Swedish Rev. of: Hasselman. H. Iaktagelser ofver skogs- 

 tradens spridningsformaga. (Observations on the power of distribution of forest trees.) 

 Medd. Statens Skogsforsoksanst. 16:27-66.] 1919.] Bot. Notiser 1919: 167-168. 1919— See 

 Bot, Absts. 4, Entry 232. 



2045. Opsahl, Waldemar. Indtryk fra en studiereise gjennem de danske skoge. [Im- 

 pressions from a trip' through the Danish forests.! Tidsskr. Skogbruk 27:209-221. 5 pi. 

 1919. — Most foresters know of the success reached in afforesting the barren heaths of Jut- 

 land, Denmark, but few have realized the years of experimentation, and the unflinching 

 faith and courage of those who fathered this project. Though several companies, which had 

 been promoted for reforesting the dunes, had failed, Enrico Dalgas became convinced that 

 it could be done and gave himself and his fortune to the work. The company which he organ- 

 ized has successfully reforested 80,000 hectares and the Danish Government 50,000 hectares. 

 The work began about 50 years ago, and at the present time only forty per cent of the total 

 waste area remains unreclaimed. One 55 year old stand of Norway spruce, planted where 

 nothing but worthless brush grew, yielded 3950 cubic feet per hectare. The work is done as 



