RHUBARB 191 



consequently less sugar is required to sweeten the sauce, 

 which is a beautiful, nearly transparent pink. 



Light. Formerly it was the customary practice to 

 force rhubarb in total darkness. Total darkness prevents 

 the development of chlorophyll; consequently the stalks 

 are whitish and the leaf blades mere rudiments. The 

 markets show a preference for a little color in the stalks 

 and for leaf blades that are slightly developed (Fig. 62). 

 When grown in diffused light, the stalks vary in shades 

 of pink, and some leaf-blade development adds to the at- 

 tractiveness of the product. The stems average longer 

 than those grown in total darkness, and some light is an 

 advantage in caring for the beds and in harvesting the 

 crop. 



The importance of diffused light should be emphasized. 

 Results will not be satisfactory if some windows are 

 covered and others admit full light. Under such condi- 

 tions the growth will be unequal and crooked stems will 

 be developed by the tops of the plants bending toward 

 the light. Diffused light may be obtained by placing 

 brown paper over all of the cellar windows, or burlap 

 along the sides of the beds, if the crop is being forced 

 under greenhouse benches. 



Principles. The large, fleshy leaves of the rhubarb, 

 which is a perennial, elaborate more food than can be 

 utilized by the parts of the plant above ground, with the 

 result that there is an unusual accumulation of nutrients 

 in the fleshy roots. An old root of a single plant may 

 weigh several pounds. When the crowns are forced 

 under favorable conditions of heat and moisture, the 

 supply of food in the roots is transformed and extended 

 into new growth. In other words, it is transferred to the 

 leaf stalks and small leaf blades. As the stalks are har- 

 vested, additional shoots appear and grow until the supply 

 of plant food in the roots is exhausted, when, of course, 

 no further growth can take place. If the roots which are 



