About Descurainia pinnata (Walter) Britton
Scientific Classification and Common Names
Descurainia pinnata (Walter) Britton is a species of flowering plant in the mustard family Brassicaceae, with the common names southeastern tansymustard and western tansymustard.
Native Range and Habitat
It is native to North America, where it grows widely across many different types of habitat, and it thrives particularly well in deserts. This hardy plant easily grows as a weed, and readily sprouts in disturbed, barren sites with poor quality soil.
General Growth Form
It is a hairy, heavily branched annual mustard that has very variable appearance. Several subspecies exist that differ from one another, and even individual plants within the same subspecies can look different based on the climate they grow in.
Size and Growth Habit
It can grow as a clumping thicket or a tall, erect mustard, and generally does not grow taller than 70 centimeters.
Leaf Morphology
Its leaves are highly lobed or divided, with pointed, toothed lobes or leaflets.
Flower Characteristics
Tiny yellow flowers grow at the tips of the plant's stem branches.
Fruit Characteristics
The fruit is a silique that measures 0.5 to 2 centimeters long, borne on a threadlike pedicel.
Reproduction Method
This plant reproduces exclusively from seed.
Toxicity and Nutritional Value
When consumed in large quantities by grazing animals, this tansymustard is toxic due to the presence of nitrates and thiocyanates; however, it is nutritious when eaten in smaller amounts.
Ecological Interactions
Its flowers attract butterflies.
Human Uses
The seeds have a flavor described as somewhat similar to black mustard, and they were used as food by Native American peoples including the Navajo.
