Witchgrass

Grass (Poaceae family):

Panicum capillare L.

EPPO code:

PANCA

Other names:

Tumble grass, tickle grass, panic grass, old witch grass, hair grass, capillary

Species information

Lifecycle:

Annual.

Propagation:

Reproduces by seed.

Emergence:

Witchgrass is an early to mid-season germinating annual grass species.

Habitat:

It is found throughout the province, but more typically in cultivated fields in central and south-central Ontario.

Competitiveness:

Agriculture and Agri-Food Canada research has shown that witchgrass densities of 20,000 plants/ac can result in a 4–5% yield loss in corn and soybeans.

Identification clues

Auricles:

None.

Ligule:

Hairy.

Leaf blade:

Densely hairy on both sides.

Leaf sheath:

The leaf sheath of witchgrass is extremely hairy, as is the leaf sheath margin.

Stem:

Round and hairy.

Seed heads:

Witchgrass’ seed head is a “fluffy” panicle with numerous fine branches resembling arterial capillaries.

Roots:

Fibrous.

Often mistaken for

I know it's not Fall panicum because witchgrass has a hairy stem and hairy leaf sheath margin while fall panicum is almost entirely smooth.

I know it's not Large crabgrass because witchgrass has a hairy ligule while large crabgrass has a membranous ligule.

I know it's not Proso millet because the leaf blade of witchgrass is extremely hairy on both sides.