Hypericum perforatum

Scientific name anchor

Use Hypericum perforatum as the species boundary; retain common names as contextual labels rather than sufficient identification.

1. Which taxonomic authority and version define Hypericum perforatum for this record? definition
2. Does the observation concern this species, another St. John's wort, or an unresolved Hypericum? boundary

Combined morphology

Record stem lines, translucent and dark leaf glands, sepal form and anther glands together, retaining photographs and unresolved characters.

1. What stem-line count and gland distribution were observed under suitable magnification? measurement
2. Which local lookalikes does the complete character combination exclude? boundary
3. Who identified the plant, using which key and voucher or photographs? provenance

Observed reproductive window

Use dated field observations to establish reproductive timing instead of assuming a universal flowering calendar.

1. When were buds, open flowers, developing capsules and releasing seeds observed at this site? measurement
2. Which inspection or management action must occur before the observed seed-release period? action

Seedlings and root regrowth

Record whether new shoots are demonstrated seedlings, connected root sprouts or of uncertain origin.

1. What observation establishes seed origin or connection to an existing root system? provenance
2. After cutting or treatment, when and where did shoots reappear? measurement
3. Does the monitoring unit represent a shoot, a rooted individual or a potentially clonal patch? boundary

Local establishment context

Record substrate, moisture, light, disturbance and neighbouring vegetation alongside location-specific status evidence.

1. What site conditions and recent disturbances accompany this population? measurement
2. Which regional flora or assessment supports its native, introduced or invasive designation here? provenance

Spread pathway evidence

Investigate seed movement through water, machinery and animals alongside root-associated expansion; these seed pathways are documented by [NSW WeedWise](https://weeds.dpi.nsw.gov.au/Weed/StJohnsWort).

1. How have occupied area, cover and detached satellite patches changed between mapped surveys? measurement
2. Which observed pathway could move seeds or viable plant material from this occurrence? provenance
3. What locally appropriate containment action addresses the evidenced pathway? action

Sample-specific constituents

Treat hypericin or hyperforin values as sample-specific analytical observations rather than fixed properties of every plant.

1. Which authenticated plant parts, developmental stage and storage conditions produced the assayed sample? provenance
2. Which analytes were measured, by what method, in what units and on what mass basis? measurement

Livestock and human-use context

Livestock ingestion can cause photosensitisation; human medicinal-use assessment requires preparation-specific review of interactions. [USDA ARS](https://www.ars.usda.gov/pacific-west-area/logan-ut/poisonous-plant-research/docs/st-johnswort-hypericum-perforatum/) [NCCIH](https://www.nccih.nih.gov/health/st-johns-wort)

1. What evidence records access, ingestion, exposed animal species and timing of any suspected livestock effects? provenance
2. Does the proposed use concern the living plant, harvested material or a separately modelled medicinal preparation? boundary
3. Which veterinary or clinical assessment is needed before making an exposure or use decision? action

Klamathweed beetle association

Chrysolina quadrigemina has been used to control H. perforatum in California and can also feed on other Hypericum species. [UC IPM](https://ipm.ucanr.edu/home-and-landscape/klamathweed-beetle/)

1. Which identified organism and life stage are associated with the observed leaf or root damage? provenance
2. What proportion of foliage is damaged, and how does damage relate to flowering and subsequent regrowth? measurement
3. If biological control is proposed, what local authorisation and host-range evidence support it? action

Persistent outcome check

Measure subsequent regrowth and reproduction rather than equating a single removal of flowering stems with elimination.

1. Is the objective to maintain a cultivated population, prevent seed escape or suppress an established patch? definition
2. Which action is supported by current local guidance, site constraints and the plant's observed stage? action
3. What follow-up interval and evidence of regrowth, recruitment and seed production will determine success? measurement

Check these first

Recalled without web access and unsourced; every item is a lead to verify.

• This account is recalled knowledge; no sources were consulted.
• Check regional floras for native-range boundaries, infraspecific classification, and identification where related species or hybrids occur.
• Verify current pharmacopoeial requirements and jurisdiction-specific regulation; evidence for a particular extract does not establish equivalent properties for every preparation.

1. Which of these check these first hold for the sense of Hypericum perforatum this model covers, and on what evidence? provenance

Identifiers and schemes

Recalled without web access and unsourced; every item is a lead to verify.

• Botanical scientific name - Hypericum perforatum L. - The author abbreviation L. credits Linnaeus; common names such as St John's wort can also refer to other Hypericum species.

1. Which of these identifiers and schemes hold for the sense of Hypericum perforatum this model covers, and on what evidence? provenance

Standards and regulation

Recalled without web access and unsourced; every item is a lead to verify.

• The European Pharmacopoeia, published by the European Directorate for the Quality of Medicines & HealthCare (EDQM), includes a monograph for St John's wort herb (Hyperici herba).

1. Which of these standards and regulation hold for the sense of Hypericum perforatum this model covers, and on what evidence? provenance

Real-world use

Recalled without web access and unsourced; every item is a lead to verify.

• Flowering aerial parts are harvested to manufacture herbal preparations.
• Certain standardized extracts are used as herbal medicines for depressive disorders in some jurisdictions.
• Oil macerates are used in traditional topical preparations.
• The plant is studied for constituents including hypericin and hyperforin.

1. Which of these real-world use hold for the sense of Hypericum perforatum this model covers, and on what evidence? provenance

Typical measurements

Recalled without web access and unsourced; every item is a lead to verify.

• Mature flowering stem height - 30-100 - cm
• Flower diameter - 15-25 - mm
• Petals per typical flower - 5 - count

1. Which of these typical measurements hold for the sense of Hypericum perforatum this model covers, and on what evidence? provenance

Failure modes and hazards

Recalled without web access and unsourced; every item is a lead to verify.

• Herbal preparations can interact with many medicines by increasing drug-metabolizing enzyme and transporter activity, potentially reducing other medicines' effectiveness.
• Combining preparations with serotonergic medicines can cause serious adverse effects, including serotonin syndrome.
• Ingestion can cause photosensitization, particularly in grazing livestock.
• The species can become invasive in pastures and other disturbed habitats outside its native range.
• Misidentification and variation in chemical composition can undermine the consistency of harvested material.

1. Which of these failure modes and hazards hold for the sense of Hypericum perforatum this model covers, and on what evidence? provenance

Regional variation

Recalled without web access and unsourced; every item is a lead to verify.

• Native broadly to Europe, parts of Asia, and North Africa, and introduced widely elsewhere.
• It is treated as an invasive or agricultural weed in parts of North America and Australia.
• Herbal products containing it have different regulatory classifications across jurisdictions, including medicinal products and dietary supplements.

1. Which of these regional variation hold for the sense of Hypericum perforatum this model covers, and on what evidence? provenance

Neighbouring kinds and how to tell them apart

Recalled without web access and unsourced; every item is a lead to verify.

• Hypericum - Hypericum is the genus containing this species and many others; the registry entry here denotes one species.
• Hypericum maculatum - A related species typically bearing four stem ridges, whereas H. perforatum typically has two; hybrids can complicate identification.
• St John's wort extract - An extract is a manufactured preparation derived from plant material, with composition dependent on processing; it is not the living species.

1. Which of these neighbouring kinds and how to tell them apart hold for the sense of Hypericum perforatum this model covers, and on what evidence? provenance