1920] HORTICULTURE. 643 



and chemical composition of our fruit-hearinf,' plants and ascertaininj^ tlie ap- 

 proximate limits within wliich variation may occur witliout producing a de- 

 crease in tlie quality jind quantity of fruit. With such knowledge at hand it will 

 be easier to prescribe treatments that will be effective in producing desired 

 results. 



Some indirect methods in extension horticulture, H. A. Cakdi.nki.l (Proc. 

 Amer. ^'oc. Hurt, iici.. Hi (I'JIU), pp. 10l>-ni).—A ccaitrihution from the Univer- 

 sity of Missouri. Tlie author discusses several extension problems in horti- 

 culture and methods by which they are being attacked in Missouri. 



The county horticultural ajjent, A. R. Jknks (Proe. Amer. Soc. Hort. Set., 

 16 (1919), pp. JU.i-166). — A discussion of the functions of tlie county horticul- 

 tural agent, including an outline of fruit, vegetable, and marketing projects 

 developed by the farmers in Middlesex County, Mass., that were under way 

 during 1919. 



The development of practical horticulture and its relation to the farm 

 bureau movement, C. E. Durst {Proc. Amer. i^oe. Hurt. ScL, 16 (1919), pp. 

 155-162). — In this paper the author suggests methods of preparing and present- 

 ing horticultural information, with special reference to its utilization by county 

 agents in farm bureau work. 



Observations on French horticulture, S. W. Fletcher (Proc. Amer. Soc. 

 Hort. Sci., 16 (1919), pp. 136-1^0). — A contribution from the Pennsylvania State 

 College comprising a brief descriptive account of horticultural industries and 

 conditions in France. 



The need of vegetable investigations, J. W. Lloyd (Proc. Amer. Soc. Hort. 

 Set., 16 (1919), pp. 111-115). — A contribution from the University of Illinois. 

 The author briefly classifies the various vegetable investigations that have been 

 conducted during recent years, and points out lines of work which are much in 

 need of investigation at the present time. 



Nature of hardening in vegetable plants, J. T. Kosa, jr. (Proc. Amer. Soc. 

 Hort. Sci., 16 (1919), pp. 190-191, figs. 3).— A contribution from the University 

 of Missouri. 



In work begun in 1917, several methods were utilized to check the growtli 

 of plants in the greenhouse, and observations were made on the nature of the 

 changes taking place. The work was conducted chiefly with tomatoes, leaf 

 lettuce, and cabbage. The methods used included partial withholding of mois- 

 ture for several weeks; growing plants on poor .sandy soil; growing plants in 

 poor soils and partial withholding of moisture comi»ined ; checking growth by 

 allowing plants to become rootbound in small pots; applications of M/10 solu- 

 tions of various salt solutions which inhibit growth ; and exposing greenhouse 

 grown plants to relatively low temperatures in a coldframe. The results se- 

 curetl are presented in tabular form and briefly discussed. 



With all of the above methods, the final effects as to hardiness to cold were 

 about the same as exposure to low temperatures in a coldframe. The outstand- 

 ing effect of these treatments upon the plant was slowing the rate of growth. 

 Other changes accompanying the checking process were an increase in dry 

 matter, greater depression of the freezing point of the .«ap, and an accumula- 

 tion of sugar, starch, and polysaccharids. In addition, it seems that there may 

 be smaller cells in hardened plant tissues. 



Fertilizer v. manure for continuous vegetable growing, B. L. Hartwell 

 and S. C. Damon (Rhode Island Sta. But. 18^ (1920). pp. 3-11).— A progress re- 

 port on the market garden experiment started at the station by F. W. Card in 

 1904, in which stable manure has been compared with chemical fertilizers for 

 continuous vegetable growing (E. S. R., 20, p. 144). 



