THE MORPHOLOGY OF WEEDS 



UJ 



occurring above ground some are 

 underground, which are often 

 merely disguised "stems," like the 

 quack grass stem. Buds are really 

 branches and bear small scales, 

 which are only modified leaves. The 

 bud terminating a branch is called 

 a terminal bud. Fleshy buds are 

 those having fleshy scales. When 

 more than one bud occurs in the 

 axil of the leaf, they are called ac- 

 cessory buds, as in the case of the 

 butternut and honeysuckle. Buds 

 also occur under the petiole of the 

 leaf, as in the sycamore, and are 

 called sub-petiolar buds. Some buds 

 are so concealed that they cannot be 

 seen until growth begins. These 

 are known as latent buds. Adven- 

 titious buds are such as develop 

 without any regular order from any 

 part of the stem or from roots. The 

 sweet potato root develops these 

 adventitious buds and many plants 

 such as the plum produce suckers 

 from them. 



The stems of grasses, lily, and 

 onion are endogenous ; the outside is 

 the epidermis and the bundles are 

 distributed through the mass. The 

 stem of pigweed is exogenous, and 

 consists of pith, wood and bark. 



Most plants of our region form a 

 definite annual growth with a ter- 

 minal bud, hickory and horse chest- j.^ 8 ' 

 nut being examples of these. Some(C. M 



