DISEASES OF PLANTS. 945 



The afforestation of the infertile lands of small estates from the stand- 

 points of agricultural and forest policy, K. Beck (Die Anfforstuny dcr iiitrrn- 

 tablen FUichen des LandicirtschuftUcheii Kleinbesitses vom Agrar- und Forstpoli- 

 tischen Stand punkte auti betrachtct, Berlin, 1908, pp. 99). — In this prize essay, 

 which is similar in character to the one noted above, the author first considers 

 the question as to what lands are suitable for afforestation purposes, and then 

 discusses the ways and means for bringing about tbls afforestation. 



Moss cover and natural regeneration, K. Bohmerle (Ccnthl. Grsain. Forstic, 

 85 (1909), Xo. 1, pp. 22-:il). — An account with the data secured is given of 

 investigations conducted at the Mariabrunn Forestry Station relative to the 

 effect of moss covered ground on natural regeneration. 



The results of this study indicate that a mossy cover, other conditions being 

 equal, is not favorable for tbe germination of seeds falling on such ground. 

 During periods of drought the mossy cover exerts a favorable influence as long 

 as it remains moist by supplying the root systems with additional moisture. 

 This influence is only temporary, however, and in tbe exiierimental areas tbe 

 number of plants growing on moss-free ground was found to be considerably 

 greater tban that growing on mossy ground. 



The plant biology of the Flemish dunes, C. De Bbuyne {Handel. Vlaamsch 

 Xatuur en Ueneesk. Cong., 10 {1906), I, No. 1-2, pp. XXXYII-LXXX, figs. 50).— 

 In this paper the author discusses the various plant formations existing on 

 Flemish sand dunes and their value for sand-binding purposes. 



The future use of land in the United States, R. Zon iU. 8. Dept. Agr. For- 

 est Seri\, Circ. 159, pp. 15, map. 1). — In this circular the author points out the 

 importance of land as a natural resource and contrasts the present condition 

 and extent of our agricultural, grazing, desert, forest, and intermediate lands 

 with their probable condition and extent 50 years from now as influenced by 

 the needs of an increased population. He shows that with an increasing de- 

 mand for land for agricultural crops there is little hope of increasing the 

 extent of forest land. He presents data drawn from forest conditions in our 

 own and other countries to support the conclusion that the growing demand 

 for wood material must be met by an increase in tbe productiveness of existing 

 forest lands and a decrease in the waste. 



Forests and reservoirs in their relation to stream flow with particular 

 reference to navigable rivers, H. M. Chittenden (Cong. Rce.. .'/5 {1909). Xo. 

 .'/7. pp. 2102-2121). — An extensive paper on \:his subject which was prepared for 

 discussion before the American Society of Civil Engineers. 



The autbor takes exception to the rather commonly accepted opinion relative 

 to the beneficial influence of forests on stream flow, and advocates the preserva- 

 tion of the forests independent of tbeir relation to tbe rivers, which latter he 

 believes can best be regulated by the establishment of reservoirs. 



Wholesale lumber prices, 1886-1908 {U. S. Dept. Agr., Forest Serv., 1908, 

 folio). — Tbis is a scbcdule of market (piotations fci* various species and grades 

 of lumber based on figures quoted by the Neir York Lumber Trade Journal, 

 the Redwood Association, and the Yellow I'ine Manufacturers' Asswiatiou. 

 The figures in most instances are based on the January prices for each year. 



DISEASES OF PLANTS. 



The development of plant pathology during the past ten years, R. Solla 

 (Riv. Fatal. Veg., 3 (1908). No. 1-3, pp. 1-36).— A summary is given of the 

 present status of i)lant pathology, and some of the more conspicuous discoveries 

 and noted advances made during the past 10 years are described at some length. 



