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DESCRIPTIVE BOTANY. 



Still another account is that it was brought into Russia from Tartary early 

 in 1700, and thence spread through Europe. 



It was introduced into northeast America by European colonists. 



Cultivation. — In latitude 40° to 45° it is sown about the 1st of July, and 

 ripens in September. It is planted when practicable upon new ground, and 

 leaves the land in a good condition for next year's planting of other crops. 

 The yield ranges in the northern and northwestern states from 20 to 50 

 bushels to the acre, but 30 bushels is a satisfactory yield. In the south Atlan- 

 tic States the yield is less, ranging from 10 to 25 bushels. 



Use. — Although this grain has not the importance of the cereals, yet 

 it constitutes the bread of a large number of the people of central Asia and 

 northern Europe. It is very popular as a material for griddle-cakes. In 

 northern Europe it is used in making a dark bread, and there too the grain is 

 hulled and used in the same manner as rice. It is an excellent feed for cattle 

 and poultry. 



BHETJM, L. Calyx colored, sepals 6, in double series, persistent; 

 stamens 9, opposite the outer sepals ; styles 3, very short and spread- 

 ing ; stigmas 3 ; fruit with 3 winged angles. Leaves large, mostly 

 radical, on long stalks. Flowers in racemose or paniculate fascicles. 

 Perennial herb. 



1. R. rhaponticum, Linn. (Rhubarb.) Stem stout, hollow, 4 feet high, 

 furrowed ; stipules large and sheathing. Leaves entire, cordate, ovate, obtuse, 



and smooth, 12 to 24 inches long and 

 10 to 15 wide, cauliue leaves smaller; 

 sepals greenish, with white margins. 

 Root large, fleshy, tuberous, and yel- 

 low within. 



2. R. palmatum, Linn. Leaves 

 5-lobed, palmate, rough ; lobes sinu- 

 ate-toothed, acute. 



.3, R. undulatum, Linn. Leaves 

 oval-cordate, Avith undulated margins. 



4. R. compactum, Linn. Leaves 

 with a general heart-shaped contour, 

 but interrupted with a number of 

 deep sinuses. 



The last three are the species 

 which furnish the rhubarb-root of 

 commerce, the R. palmatum supply- 

 ing the larger part. 

 Several varieties have been obtained by sporting and hybridizing, which 

 furnish very large leaf -stalks. There are some 10 varieties, that for one or 

 another reason recommend themselves to the cultivator. The Victoria is 

 admired for its gigantic size. The most delicate and desirable for the private 

 garden is the R. compactum. 



Geography. — Rhubarb will grow well as far north as the 50th parallel. 

 The market is supplied by the products of regions lying between 35° and 45°. 

 Unsuccessful attempts have been made in England to raise it for the druggist. 



Rheum rhaponticum (Rhubarb). 



