18 



ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 51 



Fig. 14. — In planting 

 trees with bare roots 

 the hole should be wide 

 enough to allow 1-1 Vz 

 feet of backfill beyond 

 the tips of the roots. 

 The depth should be 

 sufficient to allow for 

 the drain tile, gravel 

 fill, and 2-3 inches of 

 soil over the gravel be- 

 fore the tree is placed 

 in the hole. The bottom 

 of the hole should slant 

 toward the tile. The 

 black bars on the 

 branches indicate top 

 growth that should be 

 removed on newly 

 planted trees (see prun- 

 ing section, page 21). 



TILE 



^GRAVEL 



Fig. 15.— This twisted 

 and lopsided root sys- 

 tem resulted from im- 

 proper planting. Such 

 root systems frequently 

 do not supply adequate 

 nutrients and water for 

 normal tree growth. 



