 DESCRIPTION:
Perennial to 2'. Flowers pale yellow with 5 petals to 1" wide. Fruit
a woody, brown pod that splits down the middle and persists on the plant.
Leaves simple pinnately compound, usually with 3 pairs of leaflets per
leaf. Leaves grayish-green with fine hairs. Fabaceae
(Legume) Family.
NATURAL HISTORY: Flowers bloom in spring and fall. Flowers are buzz-pollinated.
When Carpenter Bees and bumblebees
come to the flowers, they vibrate their wing muscles, creating a relatively
loud buzzing sound(compared to the buzz of flight). This high intensity
vibration shakes pollen out of the anthers and onto the bees. Carpenter
Bees have special hairs that "catch" the pollen, and then the
bees transport the pollen to other desert sennas for pollination. For
your information, tomatoes are buzz-pollinated too (electric toothbrushes
are used in greenhouses without bees). |
