FORESTRY. 639 



" With rising sprinjj; toinporatures and absence in the pai-k of protection 

 against extremes of heat, a point is reached— the usual 'warm spell '—when 

 the layer of snow and ice in the park ' breaks up ' very rapidly and the water 

 goes off with a rush, resulting in a very small underground storage, and the 

 further consequence of a rapid drying or l)aking of the soil. 



'• In the forest, due to the high efficiency of the tree canopy in modifying sur- 

 face 'emperatures, and of the forest cover in checking the velocity of the winds 

 which at this season of the year are strong and from the southwest, and blow 

 with the regularity of the ' trades.' the progress of melting proceeds more mii- 

 formly and is prolonged into late spring or early summer with a minimum loss 

 of water by surface run-off and evaporation and a relatively high storage in 

 the forest soil." 



The effect of frost upon the green and blue forms of Douglas fir, E. Zeder- 

 BAUER (Vcntbl. Gcsam. For.stic, So (1909), \o. 8-9, pp. 381. i?SS).— Observations 

 which were made in different forests in Austria relative to- the comparative 

 resistance to frost of young trees of the green and blue forms of Douglas fir 

 (Pscudotxiiga ta.rifoita). show on the whole that the blue form (/'. ta-i-i folia 

 glauca) w-di< much more resistant than the green form, particularly in open 

 situations. 



A study of piiion pine, F. J. Phillips (Bot. Guz., J,8 (1909), No. 3, pp. 

 i]6-223). — A brief discussion of the piiion pine (Pinus edulis) relative to its 

 general distribution, local occurrence, tolerance and form. wood, fruit, reproduc- 

 tion, and future management. 



Eucalypts cultivated in the United States, C. Westekgaard, Jr. (Forestry 

 Quart. . 7 (1909). No. ,1 pp. 280-.i0,3). — Descriptions are given of the species of 

 eucalypts most generally cultivated in the southwestern United States, relative 

 to their identification, growth, wood and its uses, climatic requirements, and 

 occurrence. 



Four years' experience growing rubber trees on Basilan, C. F. Miller 

 {Philippine Agr. Rev. [English Ed.], 2 (1909), No. 7. pp. 395-40.',).— A brief 

 account of the author's experience in growing the Ceara rubber tree (Munihot 

 gl(iziorii) on Basilan. Philippine Islands. Consideration is given to germination 

 and planting, pruning, tapping, coagulation, the raw rubber, and soils. Fifty 

 trees 3* years old when taitped yielded a total of o lbs. of rubber. Each tree 

 was tapped 3 times, thus giving a little over i oz. per tree for each tapping. 



A list of the trees of the State of Florida, J. Gifeord (Cocounut Grove, Fhi., 

 1909, pp. 24). — This consists of a list of some 281 species which are either native 

 to or have been introduced into Florida. Both the botanical and common names 

 are given, and the locality as well as the economic value of the more imi)ortant 

 species are indicated. 



Native trees of the Hudson River Valley, N. Taylor (Bui. S. Y. Bot. 

 Garden. 7 (1909). No. 23, pp. 90-l.'i7. pis. 20).— This consists of a descriptive 

 list of trees known to grow naturally in the counties of New York and New 

 Jersey bordering the Hudson River. 



Forest flora and forest resources of Portuguese East Africa, T. K. Sim 

 [Aberdeen, 1909, pp. VI+166, pis. 700).— This is a handbook of the forest flora 

 of Portuguese East Africa published under the authority of the Mozambique 

 (government and based on the author's observations, together with other avail- 

 able data. The work is indicative of the forest wealth of that region. Part 1 

 contaiiis a general description of the country, and of the forests relative to their 

 constitution and locality, synoptical and si)ecitic botanical descriptions of the 

 forest flora, and an account of the timbers and miscellaneous economic products 



13042—09 1 



