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SEASONAL IDENTIFICATION
WILD MUSTARD (Sinapis arvensis)
SPRING
-
LATE
SUMMER
SUMMER
-
FALL
SUMMER
-
FALL
SPRING
SPRING
-
SUMMER
LATE
SUMMER/FALL
-
WINTER
Young wild mustard is short growing with leaves growing
low to the ground. The leaves are generally oval shaped with
one to two lobes near the base of the leaf.
When in flower, large colonies of wild mustard are easy to
spot at a distance. Wild mustard can germinate in spring
and flower by summer or germinate in summer and flower
by fall.
As wild mustard matures and seeds have developed, the
plant lacks flowers and leaves in the upper branches. Note
the visible seed outline near the tip of the seed pod.
Leaves have a toothed margin and vary in shape and size.
Short stiff hairs are found on the underside of leaves on
stems. Purple coloring can be found where a branch meets
the stem.
The yellow flowers are 1–2 inches wide with four petals. The
flower grows in a cluster of multiple flowers at the end of the
upper branches.
After maturing and producing seeds, wild mustard may
turn bright red before it dies. Red color change is more
frequent in plants that mature by summer. Plants that
germinate in fall may be killed by frost before flowering and
producing seeds.