Hypericum perforatum - Brassicaceae Family - Perennial
Prevention (Prev) Monitor and destroy new plants before seed production.
Mechanical (Mech) Hand pulling, digging, cutting, mowing and tilling.
Cultural (Cult) Biological control agents, livestock grazing, and revegetation practices.
Chemical (Chem) Selective herbicides based on the plant and the specific location. Check our weed fact sheets for specific control information.
St. John's wort: flower
St. John's wort: foliage
St. John's wort: full plant in bloom
St. John's wort: infestation
St. John's wort: seedling
St. John's wort: seed
St. John's wort going to seed
J.M., G.B. Kyser et al. (2013). Weed
Control in Natural Areas in the Western United States [PDF file]. Weed
Research and Information Center, University of California. Retrieved from https://wric.ucdavis.edu/information/natural%20areas/wr_H/Hypericum_perforatum.pdf
Invasive Species Database. (2017, August 8). Species profile: Hypericum perforatum. Retrieved from http://www.iucngisd.org/gisd/species.php?sc=1197
& Johnson, W. Managing common St.
Johnswort [PDF file]. Retrieved from https://www.unce.unr.edu/publications/files/nr/2003/FS0314.pdf
Species Consortium. (2018, January 3). Hypericum
perforatum (St John’s wort). Retrieved from https://www.cabi.org/isc/datasheet/28268
Sheley, R., & Brown, M. (2017, June). St.
Johnsort: identification, biology, and integrated management [PDF file].
Retrieved from http://www.msuinvasiveplants.org/documents/mt_noxious_weeds/St.%20Johnswort_MT199810AG.pdf
State Noxious Weed Control Board. Common
St. Johnswort. Retrieved from https://www.nwcb.wa.gov/weeds/common-st-johnswort
Health Technology Enterprise Team. (2012, May). Biology and biological control of common St. Johnswort [PDF file].
Retrieved from https://www.fs.fed.us/foresthealth/technology/pdfs/FHTET-2010-05_StJohnswort.pdf