Dwarf Rush (Juncus capitatus)
Key Details
| Taxonomic Groups: | Vascular plant > flowering plant > Rush |
| Red List Status: | Vulnerable (Not Relevant) [VU(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: | Juncus capitatus |
| UKSI Recommended Authority: | Weigel |
| 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: | Confined to Cornwall in mainland England, with extant populations on the Lizard & an outlier at Nare Head (East Cornwall). Formerly also in two sites in West Penwith. Currently recorded from c 15 broad locations since 2000 (historically in c. 22 sites) on the Lizard. Pearman (2017) records a loss of 39% of sub-sites on the Lizard in 8 year period to 2016. |
| Question 2: | Does recovery/ conservation depend on species-specific actions? |
| Response: | Yes |
| Justification: | Targeted conservation of serpentine rock outcrops in coastal zone & coastal valleys needed to restore lost populations |
| 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: | Yes |
| Justification: | Widespread reintroduction of extensive grazing to coastal slopes & heathland has unquestionably aided species, but more widespread grazing / disturbance of outcrop grasslands likely to encourage further spread |
Species Assessment
| Current step on the Species Recovery Curve (SRC): | 7. Best approach adopted at appropriate scales |
| Recovery potential/expectation: | Medium-high |
| National Monitoring Resource: | Combination - insufficient |
| Species Comments: | Loss of up to 39% of subsites since 2008 probably due to (i) increased height of vegetation (both grass & scrub), (ii) build-up of dry organic litter/mor humus, & (iii) proliferation of pleurocarpus mosses all leading to loss of bare mineral soil microsites for germination & growth. Species responds well to summer drought, & often relatively abundant in year immediately following drought year. |
Key Actions
Key Action 1
Proposed Action: Maintain or introduce programme of practical management at all sites known since c. 1950 including scrub clearance, moderate to heavy extensive grazing etc
Action targets: 7. Best approach adopted at appropriate scales
Action type: Habitat management
Duration: 3-5 years
Scale of Implementation: ≤ 20 sites
High priority sites: Mullion Cliff to Predannack Cliff SSSI. Caerthillian to Kennack SSSI. Kennack to Coverack SSSI. Goonhilly Downs SSSI
Comments: Significant management work currently underway (2023-2025) through Species Recovery Programme within West Lizard SSSI.
Key Action 2
Proposed Action: Maintain database (established by David Pearman & Cornish botanists) of all current or post 1950 sites, to include known population size/extent, history and management. Monitor all populations on 1-3 year cycle.
Action targets: 3. National Monitoring Plan agreed and implemented
Action type: Targeted monitoring
Duration: >10 years
Scale of Implementation: ≤ 20 sites
High priority sites: As listed under action 1
Comments:
Key Action 3
Proposed Action: Undertake research into role of humus (undecomposed dry litter & mor humus) & pleurocarpous moss growth in negatively impacting survival of this & associated species. Review roles of grazing & disturbance in mitigating impacts.
Action targets: 4. Autecology and pressures understood
Action type: Scientific research
Duration: 3-5 years
Scale of Implementation: ≤ 5 sites
High priority sites: West Lizard SSSI. Kennack to Coverack SSSI
Comments: Introduction of conservation grazing does not appear to have entirely reversed fortunes of species. More detailed assessment of causes at the micro-level required.
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.