Content tagged with "weed"

Black Mustard

Photo of black mustard flower cluster
Brassica nigra
Next time you breeze past weedy black mustard on the highway or spot it in a fallow field, think of how important this and other mustards are to the world economy – and to your dinner table. More

Black Mustard

Photo of black mustard plant growing in cracked pavement
A native of Eurasia, black mustard is weedy and grows in fields, waste places, roadsides, and other disturbed areas. Until it was recently replaced by another species (brown mustard, which also is naturalized in Missouri) black mustard was the chief source of seed used in making table mustard. More

Black Mustard

Photo of black mustard plants on the edge of a field
Black mustard can grow to 5 feet tall. Next time you breeze past weedy black mustard on the highway or spot it in a fallow field, think of how important this and other mustards are to the world economy – and to your dinner table. More

Black Mustard (Flowers)

Photo of black mustard flower cluster
The flowers of black mustard are very small, yellow, and about 3/8 inch wide, with the 4 petals arranged like a cross. It blooms April–November. The fruits are long seedpods (technically, siliques) that form lower on the stalk as new flowers develop higher up. More

Black Mustard (Leaves)

Photo of black mustard leaves
The leaves of black mustard have long petioles and are highly variable, often irregularly lobed to the midrib, generally ovate, some with teeth. More

Canada Thistle

Photo of Canada thistle flowers
Canada thistle is a native to Eurasia and arrived on our continent probably before the Revolutionary War—most likely mixed in agricultural seed. A bad weed of crop fields and rangeland farther north, it causes problems in Missouri, too. More

Canada Thistle

Photo of Canada thistle flowers
Cirsium arvense
Canada thistle is a native to Eurasia and arrived on our continent probably before the Revolutionary War—most likely mixed in agricultural seed. A bad weed of crop fields and rangeland farther north, it causes problems in Missouri, too. More

Common Teasel

Photo of common teasel flowering heads
Dipsacus fullonum
“Infestation” is the term for what teasels are doing in Missouri. Learn to identify these thistlelike plants, and help to control the weedy spread of these tough, prickly invaders. More

Common Teasel

Photo of common teasel flowering heads
“Infestation” is the term for what teasels are doing in Missouri. Learn to identify these thistlelike plants, and help to control the weedy spread of these tough, prickly invaders. More

Cornflower (Bachelor’s Button) (Flowerhead)

Photo of a cornflower, closeup of a flowerhead.
A member of the thistle tribe of composites, cornflower lacks true ray florets; instead, the outer florets of each head have enlarged, flaring corolla tubes that at a glance look something like the strap-shaped extensions of true ray florets. More