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 
