154 AGRICULTURAL BOTANY 



and Corms. --In many grasses branches often lie 

 along the ground or under the ground, take root at 

 their nodes, and send up new plants. Such a branch 

 is called a stolon or runner if it lies on the ground, and a 

 rootstock if it lies under the ground. The strawberry, 



FIG. 75. Stolons of Black Raspberry. 



black raspberry, and white clover are propagated by 

 means of stolons, and Kentucky blue grass by root- 

 stocks. Bermuda grass is propagated by rootstocks and 

 stolons. These methods of reproduction enable plants 

 to perpetuate themselves after the original plants from 

 seed are dead. The dense sod of lawns and pastures is 

 due to propagation by stolons and rootstocks. 



A sucker is a branch which springs from a parent stem 

 underground where it makes roots of its own, then 

 farther on rises above ground into a leafy stem and 

 becomes an independent plant whenever the connec- 

 tion with the parent plant is broken. The rose, the 

 blackberry, and the red raspberry are propagated by 

 suckers. 



Note- Suckers appearing at the base of the same stalk or in the 

 axils of the leaves of the tobacco plant are not used for propagating 

 plants. 



