Hypericum perforatum - St. John's Wort


Family Hypericaceae



St. John's wort is a rhizomatous perennial that spreads via seed and creeping rhizomes.  It is prevalent throughout the Willamette Valley.  It can become weedy in Oregon nursery stock, although I rarely see it well-maintained fields.

St. John's wort

The most unique identifying characteristic of the plant are its leaves.  Each leaves contain a number of translucent glands, which when held up to the sun make it appear as if the leaf were perforated (hence the name).

St. John's wort

Leaves are sessile and arranged oppositely along the stem.

St. John's wort hypericum

Stems are reddish in color.  They are also flattened, and the direction in which the stems are flattened rotates 90 degrees at each node.

St. John's wort hypericum



Flowers are yellow and occur in clusters called cymes.

St. John's wort


St. John's wort

Each flower has 5 petals and numerous stamens.

St. John's wort




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