Compass Plant

Compass plant is a long lived, perennial member
of the sunflower family. Its basal leaves and stems all
arise from an underground crown. A large reddish brown
tap root 1 to 2 inches in diameter is located just below the
crown. The tap root rapidly looses diameter as it descends
up to 16 feet into the prairie soil. The large basal leaves
can be 15 to 24 inches long and are deeply cut like a giant
pin oak leaf. The rigid, sand paper like leaves orient
themselves in a north to south direction to avoid the direct
rays of the midday sun, thus leading to the plants common
name, compass plant. Stems are erect and number from
one to several with an overall height of from 3 to 10 feet.
The simple leaves are alternately arranged on the stem
and are less divided, smaller and have direct attachment
higher up on the stem. Leaves are leathery and stiff with
rough surfaces and hairs occurring on the leaf main veins.
Large yellow flower heads from 2 to 4 inches across are
conspicuous on the upper half to two thirds of the stem in
small clusters. Flowering begins in late June and proceeds
through August. Flower heads begin opening at the top of
the stem first. There are 15 to 34 narrow yellow petal
flowers (ray florets) that are 1 to 2 inches long. The center
of the flower contains the numerous disk florets with
yellow corollas. The fruit is a flattened achene about ½
inch long with a notched tip. Achenes develop on the
outside of the head since the ray florets are the only fertile
seed producing units on the flower.