272 



JOUENAL OF THE ROYAL HORTICULTURAL SOCIETY. 



figs. 95-99 ; April 21, 1906).— The art of pruning," the author says, 

 " may be said to serve one or more of the following purposes : — To 

 improve or alter the shape or appearance of the plant ; to increase the 

 quantity and improve the quality of the blossom ; to bring about an 

 improvement in health. Of all the arts which are employed in horticulture, 

 pruning is the one most frequently misapplied. Bad pruning is worse 

 than none." He then gives details of how and when, according to the 

 kind of plant, this operation should be performed. Good figures are 

 given of the right and wrong ways of cutting off boughs of trees. 



G, S. S. 



Radium {Le Jar din, vol. xx. No. 457, p. 65 ; March 5, 1906). —Vadium, 

 as elperimentally studied by Dr. Gayer, appears to have a deleterious 

 effect on seeds. Where its action preponderates, germination may be 

 retarded, and even completely arrested. Other radio-active substances, 

 such as radio-tellurium, give similar results, while polonium appears to 

 have no distinct action. — F. A. W. 



Rhodora canadensis. By Jean Beziat (Le Jardin, vol. xx. 

 No. 456, p. 57, fig. ; February 20, 1906). — A charming shrub of 

 Canadian origin belonging to the Ericacem. It grows between three and 

 four feet in height, and is covered with a profusion of red rose- scented 

 flowers. It is perfectly hardy and more ornamental than Daphne mezereoUf 

 wdth which it is comparable. — F. A. W. 



Rhubapb, Ether Forcing- of (U.S.A. Dep. Agr., Farm. Bull. 233 ; 

 1905). — The application of ether vapour to rhubarb in a dormant state 

 resulted in the total yield being increased from 5 to 34 per cent., while, 

 with one exception, the early yield was very greatly in excess over the 

 untreated plants. The exception was when the etherisation was delayed 

 until the beginning of February. — F. J. C. 



Roots of Plants. By A. M. Ten Eyck (U.S.A. Exp. Stn. Kansas, 

 Bull. 127 ; June 1904 ; 26 figs.). — The author has investigated the extent 

 of the root systems of plants, and gives photographic reproductions of the 

 root systems of several farm and garden plants, with a description of the 

 method of investigation. — F. J. C. 



Rose-growing- in Pots. By P. (Garden, No. 1788, p. 116 ; 

 February 24, 1906). — If purchased in 5 -inch or 6-inch pots, the plants 

 should be transferred at once to a size larger. Make up a mixture of 

 loam, which can be obtained from a meadow, just beneath the grass. Three 

 parts of this and one part of well-rotted manure make good rose soil if well 

 mixed together. Have the new pots ready washed, and place in each some 

 crocks, one large piece over the hole, and a few other smaller pieces. Put 

 a handful or so of soil on the crocks, then the plant, having first removed 

 the old crocks. The ball of earth should be lightly prodded wdth a 

 pointed stick to release the roots a little. Press the new soil firmly 

 around the ball, and ram it tight with a stick. If plants in 7-inch or 

 8-inch pots are procured, no repotting will be necessary the first year. 

 Never have the pots over-large : that is to say, when repotting is necessary 



