Annual Knawel (Scleranthus annuus)
Key Details
| Taxonomic Groups: | Vascular plant > flowering plant > Herbaceous plant |
| Red List Status: | Endangered (Not Relevant) [EN(nr)] |
| D5 Status: | Included in the baseline Red List Index for England (Wilkins, Wilson & Brown, 2022) |
| Section 41 Status: | (not listed) |
| Taxa Included Synonym: | (none) |
| UKSI Recommended Name: | Scleranthus annuus |
| UKSI Recommended Authority: | L. |
| UKSI Recommended Qualifier: | (none specified) |
| Red List Citation: | in Stroh et al., 2014 |
| Notes on taxonomy/listing: | (none) |
Criteria
| Question 1: | Does species need conservation or recovery in England? |
| Response: | Yes |
| Justification: | Assessed as EN in England by Stroh et al. (2014) due to a 67% decline in AOO and a 64% decline in EOO. This species has mainly declined in arable habitats as a result of intensification of management practices. |
| Question 2: | Does recovery/ conservation depend on species-specific actions? |
| Response: | Yes |
| Justification: | Subsp. annuus is likely to be more effectively recovered as part of wider schemes to restore acid/grassland heathland and/or through targeted options for arable plants on sandy or calcareous soils. However, the recovery of subsp. polycarpos will require site specific actions. The data in this line regards subsp. polycarpos only. |
| Question 3: | At a landscape scale, would the species benefit from untargeted habitat management to increase habitat mosaics, structural diversity, or particular successional stages? |
| Response: | No |
| Justification: | Subsp. polycarpos needs targeted actions |
Species Assessment
| Current step on the Species Recovery Curve (SRC): | 2. Biological status assessment exists |
| Recovery potential/expectation: | Medium-high |
| National Monitoring Resource: | Structured - sufficient |
| Species Comments: |
Key Actions
Key Action 1
Proposed Action: Undertake a survey of historic sites of subsp. polycarpos to establish population sizes, habitats, threats and current management
Action targets: 2. Biological status assessment exists
Action type: Status survey/review
Duration: 2 years
Scale of Implementation: ≤ 50 sites
High priority sites:
Comments:
Key Action 2
Proposed Action: Collect seed from subsp. polycarpos existing sites and grow on for potential reintroduction
Action targets: 5. Remedial action identified
Action type: Ex situ conservation
Duration: 3-5 years
Scale of Implementation: Unknown
High priority sites:
Comments:
Acknowledgment:
Data used on this website are adapted from Threatened species recovery actions 2025 baseline (JP065): Technical report and spreadsheet user guide (Natural England, 2025). Available here.