fall panicgrass
Family
PoaceaeScientific Name
Panicum dicotomiflorum
Other Common Names:
western witchgrass
Habit
Seeds germinate in late spring or early summer and plants quickly grow to heights between 20 in to 40 in. Plants are erect to sprawling and often root at the nodes of bent stems.
Leaves
Seedling leaves are hairy on the bottom but not on the top. Hairs are common on young seedlings but become less common on upper leaves of older plants. Plants lack auricles and stems are smooth. The ligule is split with the top fringe being hairs and the lower portion a solid membrane. Overall the hairy ligule is shorter than that of the foxtails (1 to 2 mm long).
Identifying Characteristics
Stems grow in a zigzag fashion, turning at each swollen node. Stems are shiny and hollow when cut open. Older plants resemble Johnsongrass in that leaves are wide and large but Johnsongrass stems are solid and the plants are erect, not sprawling. Young seedlings have thin cotyledons, hairy ligules, and hairs only on the bottom of lower leaves.
Flower Seed Head
The seedhead is an open panicle that is up to 16 in long and may appear green or purplish at maturity. Each spikelet produces a single light brown seed.
Seed Fruit
Seeds are awnless, light brown and about 1.5 to 2 mm long.
Where Found
Typically a weed of cultivated areas such as home gardens, row-crop agriculture, and nursery beds. Seed will germinate in open or disrupted areas of turfgrass and are not uncommon in turf in mid to late summer. Although plants may occur in turfgrass, they are much less common than other summer annual grassy weeds such as crabgrass and goosegrass.
Leaf Hair on Upper Surface
Varies:
no hairs,
hairs from base to tip
Leaf Arrangement
rolled in bud
Mature Leaf Width
Varies:
6 to 15 mm,
more than 15 mm
Stem
round
Seedhead
panicle
Root Structure
fibrous
Life Cycle
summer annual
Auricle
not present
Ligule
hairy
Ligule Length
Varies:
1-2 mm,
2-3 mm
Plant Type
Grass