Grass foliage and plume forms can be categorized into six groups.  The categories describe the general form regardless of the plants foliage or plume height.

	Tufted (T) - Foliage is usually spiky or fine-textured with upright leaves.  Example: Pennisetum alopecuroides 'Little Bunny'.
	Mounded (M) - Foliage is somewhat weeping, mounding foliage.  Top growth covers the lower leaves.  Example: Pennisetum alopecuroides.
	Upright (U) - Foliage/Plume grows vertically in a uniform or even columnar form.  Example: Panicum virgatum 'Northwind'.
	Upright Divergent (UD) - Foliage/plume grows up and out in an erect or stiffly ascending manner.  Example: Helictotrichon sempervirens.
	Upright Arching (UA) - Foliage/Plume ascends vertically then become fountain-like at the top.  Example: Miscanthus sinensis 'Sarabande'.
	Arching (A) - Foliage/Plume arches up and out, in somewhat equal proportion. Example: Calamagrostis acutiflora (x) 'Karl Foerster'.

 (Images from The Encyclopedia of Ornamental Grasses by John Greenlee, Rodale Press, 1992)