STEMS AND BRANCHES AND THEIR USES 199 



of each leaf a bud is formed, which may grow either into an 

 underground branch similar to the main stem, or into an erect 

 branch that will push above the surface of the ground in the 

 spring and bear leaves, flowers, and fruit. In the formation 

 of such erect branches, the may-apple and many other seed 

 plants with underground stems differ from the bracken 

 fern, which sends only leaves above the surface of the ground. 

 As in the case of the fern, the older part of the may-apple 

 stem dies as the younger part grows. 



In many plants, as for example in the Solomon's seal (Fig. 

 120), it is not an axillary branch but the end of the stem 

 itself that turns 

 upward and 

 bears leaves and 

 flowers. The 

 erect part of the 

 stem dies in the 

 fall, but the for- 

 ward growth is 

 continued under- 

 ground by the 

 last -formed axil- 

 lary bud. This 



bud grows into a short branch that appears to be an ex- 

 tension of the main stem ; the growing end of this branch 

 in turn the next spring pushes up above the ground. The 

 underground part of the plant, therefore, though it looks like 

 a continuous stem, is really made up of a series of short 

 branches. The large markings that give the name to the 

 Solomon's seal are the scars left, one each year, by the death 

 of the upright shoots. Many grasses and sedges are remark- 

 able for their long, branching, underground stems. That 

 of the quack-grass can be cut up into small pieces, each of 

 which may become an independent plant. This is why quack- 

 grass is so troublesome a weed. The formation of a sod by 



FIG. 1 20. Underground stem of the Solomon's 

 seal (Polygonatum), showing the joints that mark the 

 growth from year to year, and the scars ("seals") 

 left by the death of the upright shoots. 



