Hypericum perforatum - St. John's Wort
St. John's wort is a rhizomatous perennial that spreads via seed and
rhizomes. It is prevalent throughout the Willamette Valley.
can become weedy in Oregon nursery stock, although I rarely see it
The most unique identifying characteristic of the plant are its leaves.
leaves contain a number of translucent glands, which when held up to
sun make it appear as if the leaf were perforated (hence the name).
Leaves are sessile and arranged oppositely along the stem.
Stems are reddish in color. They are also flattened, and the
in which the stems are flattened rotates 90 degrees at each node.
Flowers are yellow and occur in clusters called cymes.
Each flower has 5 petals and numerous stamens.
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