262 FORESTRY [BoT. Absts., Vol. VIII, 



the Balkans such stands are managed under a rough selection system. The sprouts suffer 

 much less from grazing damage, wind and snow breakage, and dryness than when clean cut; 

 but due to light deficiency there is poorer development, and suppression may ultimately lead 

 to bad openings in the stands. Felling is very much more difficult than when a clean-cutting 

 method is used as the stands are dense and trees lodge badly. The author does not advocate 

 the method, merely describes it, but presumes that it is much better adapted to southern 

 countries than to those farther north, since sprouting under deficient light is much better 

 in the south, — F. S. Baker. 



1851. Greenfield, W. P. The sand-dunes of the Lincolnshire coast. Quart. Jour. 

 Forest. 14: 176-184. 1920. — A general discussion of the sand dunes of the region and a plan 

 for their reclamation. Afforestation cannot be considered as an actual means of sea-defense ' 

 but should be a secondary operation following the fixing of the sand by means of the marram 

 grass. Corsican pine at Holkham in Norfolk has proved the best species for planting on 

 open parts exposed to sea breezes. In growth and hardihood, it far surpassed the Scotch 

 and maritime pines. — C. R. Tillotson. 



1852. Guthrie, J. D. The national forest resources of Alaska are for use. Amer. 

 Forestry 27: 12-14. 5 fig. 1921. 



1853. Hartel, 0. 1st die Wildbachverbauung notwendig? [Is control of torrents neces- 

 sary?] Wiener Allg. Forst- u. Jagd-Zeitg. 38: 171-172. 1920.— This question is treated under 

 two heads: (1) How far is the great expense of torrent control economically justified, and 

 (2) can poverty-stricken Austria afford the luxury of this control? The author shows that 

 reforestation, protection, and careful regulation of the use of the watersheds, where the 

 streams are small, helps greatly in ameliorating conditions in the main channels. Expensive 

 engineering works have in the past been constructed in some places where only full protection 

 of the upper slopes was needed. The work of the forester is inexpensive and can be carried 

 on generally; expensive engineering works can be constructed if needed, following protection 

 of the headwaters. Secondly, the author shows that Austria must control torrents both in 

 view of hydro-electric developments and agriculture in the valleys. — F. S. Baker. 



1854. Headley, R. Fire protection to save our forests. Amer. forestry 26: 710—714. 

 4 fig. 1920. 



1855. Henkel, J. S. Forestry in Rhodesia. Improvement fellings on the farm. Rhodesia 

 Agric. Jour. 18: 76-79. 1921. 



1856. Henkel, J. S. Forestry in Rhodesia. The management of woods. Rhodesia 

 Agric. Jour. 17: 408-411. 1920. 



1857. Henry, Augustine. The artificial production of vigorous trees by hybridisation. 

 Quart. Jour. Forest. 14: 253-257. 1920. — First generation hybrids in trees as in other plants 

 are remarkable for their size, rapid growth, early and free flowering, ease with which they 

 can be multiplied, and, in all probability, their comparative immunity to disease. The slow 

 growth of the ordinary species of oak, ash, and walnut, except on the best agricultural soils, 

 renders hopeless all possibility of an adequate financial return. Without vigorous 1st genera- 

 tion hybrids, the most valuable classes of timber can be grown only in limited quantity. 

 There is the possibility of obtaining vigorous hybrids of the valuable species capable of thriv- 

 ing on soils ordinarily inhospitable. The relation of vigor in hybrids to the degree of rela- 

 tionship between the parents is unknown but of practical interest in the selection of parents 

 for crossing experiments. Very little has been done in hybridization of forest trees. Klotzsch 

 carried on experiments in 1845, at Berlin, with pine, oak, alder, and elm, and after 8 years 

 the hybrids averaged 5 larger than the parents. Burbank's work with walnut in California 

 has resulted in progeny of greater vigor. The author has produced a very vigorous hybrid, 

 Populus generosa. Experiments carried out at Kew during the war with Fraxinus excelsior, 



