Search By Location 
 

St. John's-Wort (Hypericum)

section divider
Home « Hypericum

St. John's-Wort Genus Details

section divider
St. John's wort is native to S.E. Europe and Asia. It is generally used as a ground cover and it is drought tolerant. Bright yellow flowers appear in late July and are 3" in diameter. In autumn, the flowers turn purple. St. John's Wort is used in herbal medicine as a mood enhancer.
Common St. John's-Wort (Hypericum perforatum).
Common St. John's-Wort (Hypericum perforatum).
Common St. John's-Wort (Hypericum perforatum).
Common St. John's-Wort (Hypericum perforatum).

St. John's-Wort Allergy Info

section divider
Generally low to moderate allergic reactions have been noted with this genus.

St. John's-Wort Pollen Description

section divider
Grains are subprolate; the amb triangular and 3-colporate. The colpi are long and narrow and slightly constricted equatorially. The ora is lalongate and the opercula granular. The sexine is reticulate and the lumina small and polygonal. The intine is thin and thickened below the apertures.
Grains are 21-24 x 18-19 micrometers.

Species in This Genus

section divider
Allergenicity Legend:
Mild Allergen Mild Allergen  |  Moderate Allergen Moderate Allergen  |  Severe Allergen Severe Allergen  |  Allergy Test Allergy Test Available
St. John's-Wort (Hypericum) is a genus of the CLUSIACEAE family.
This genus includes the following allergenic species:

Allergens and Plants Search

section divider Enter a full or partial species name to find more information on one of over 1200 potentially allergenic plants. For example, you can find chenopods searching on "cheno" (no quotes) as Latin Name.

Search By Plant Name:
 
 Common Name    Latin Name

Search By Alphabet:
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Advertisement

St. John's-Wort Genus Location

section divider
The shaded areas on the map indicates where the genus has been observed in the United States. Click the map to see a full scale version of these allergy areas.
  - Native, observed in a county
  - Introduced, observed in a county
  - Rarely observed

Related Links

section divider
Advertisement
facebook_twitter

Advertisement