NOTES AND ABSTRACTS. 



367 



ether, but is much stronger in its action. Greater precaution is, 

 therefore, required in its use. 



It had been known for some time that if HIies of the valley and 

 some other plants had been plunged into a warm-water bath for some 

 hours and then brought into a warm greenhouse their blooming could 

 be considerably accelerated. The influence of the warm-water bath 

 was first studied in detail by Hans Molisch in 1908-09. The most 

 convenient apparatus for applying the warm-water treatment was 

 described by Molisch, and is reproduced in Burgerstein's account. 

 Molisch found that a nine to twelve hours ' treatment with water of a 

 temperature of 30O-50° C. gave the best results. If lilacs are re- 

 quired in bloom at Christmas the branches should be plunged into water 

 at a temperature of 35° C. for ten to twelve hours and then removed 

 to the forcing house, when they will come into flower eight to twelve 

 days earlier than those not treated with warm water. 



Alb. Hoffmann, using the warm- water bath treatment had branches 

 of the lilac Charles X in flower on December 1 and some branches of, 

 Marie Legraye a few days earlier than this. The court gardener 

 Kleine treated some rhizomes of lily of the valley in the middle of 

 November with a water bath at a temperature of 38° C. for fourteen 

 hours, and was able to bring them into flower in three weeks. 



Besides the above it has been found possible to flower the following 

 plants at Christmas by the use of the warm-water bath : Prunus 

 triloba, Malus S cheideckeri , Wistaria sinensis, Viburnum, Forsythia. 

 The same treatment was also very successful for Azalea indica and 

 some roses (' Frau Karl Druschki '). 



Exposure to steam has a similar effect to the warm-water bath in 

 accelerating the appearance of bloom upon plants which are being 

 forced, but for practical purposes the water bath is to be preferred. 

 Another means of assisting the forcing of plants into bloom is furnished 

 by low temperatures. Plants which have been subjected to frost will 

 subsequently force much more quickly than those which have not. 

 Burgerstein gives details of the researches which have been carried 

 out on this subject, and he also deals with the drying of plants as an 

 aid in their forcing. — R. B. 



Forest Cover and Avalanches in the Northern Cascades. 



By Thornton T. Hunger {U.S.A. Dep. Agr., Forest Se Tvice, Circ. 173 ; 

 Nov. 24, 1911). — Avalanches are of frequent occurrence in the 

 Northern Cascades, and it is the object of this pamphlet to point out 

 what may be and has been done by tree planting to obviate the evil. 

 The preventive measures to be adopted are fully discussed. 



A. D. W. 



Forest, Crater National. By Findley Burns (U.S.A. Dep. Agr., 

 Forest Service, Bull 100; Nov. 28, 1911).— An interesting account of 

 the Crater National Forest, which lies southwards from the Crater Lake 

 National Park, one oi the natural wonders of America, and visited 



B B 2 



