Jointleaf Rush Juncus articulatus
Jointleaf Rush is a perennial grass native to Alaska, Canada, and the lower 48 states. It grows to 2 ft and blooms Jun in full sun – part shade, with brown fruit.
More about this plant
Juncus articulatus is a flowering plant species in the rush family Juncaceae. It is known by the common name jointleaf rush or jointed rush, which can also refer to J. kraussii from Australia. It is native to Eurasia, Canada, Greenland and much of the United States. It grows in moist areas, such as wet sand, and thrives in calcareous soils. J. articulatus was found to be more sensitive to drought and salt stress than its congeners J. acutus and J. maritimus. It is a perennial herb producing mainly erect stems from a short rhizome. The stem may root at nodes, and it generally has one or more flattened hollow cylindrical leaves up to 10 centimeters long. Transverse internal partitions or joints may be seen or felt in the leaf of the plant. Wikipedia →
Growing & care
USDA PLANTS · TRY- Sun
- Full sun – part shade
- Soil & moisture
- High moisture
- Soil pH
- 4.8–7.5
- Fertility need
- Medium
- Adapts to
- Coarse (sandy), Medium (loam), Fine (clay)
- Hardiness
- USDA zone 5+
- Height
- 2 ft
- Spacing
- 2–3 ft apart from USDA planting density
- Spread
- Slow
- Growth rate
- Moderate
- Growth form
- Rhizomatous
- Lifespan
- Perennial · moderate
- Foliage
- Evergreen broadleaf · fine texture
- Active growth
- Spring & summer
- Fruit
- Brown
- Flower colour
- Brown AI AI image-analysis of community-science photos (~87% expert agreement) — not a botanical record
- Propagate by
- Seed, Bare root, Sprigs
- Seed starting
- No stratification needed
- Seeds ripen
- Summer seed-collection / harvest window
- In the trade
- Routinely available
- Deer browsing
- Low often deer-resistant
- Resprouts if cut
- No
Sow timing keys off your local last- and first-frost dates.
Wildlife & pollinators
How pollinator value is scored →❧ Caterpillar hosts ~6 caterpillar species
Juncus supports ~6 caterpillar species.
Native butterfly & moth caterpillars are the base of the terrestrial food web — most songbirds rear their young almost entirely on them. As a host for native Lepidoptera this is a modest genus.
Recorded feeding on Juncus in North America, including:
+ 8 more species → ↑ show fewer
Related plants
More Juncus →
How we know this (4) Methods & honest limits
We read each species’ measured specific leaf area (leaf area per unit dry weight) from the Global Spectrum dataset and band it: thin & fast (high SLA), medium, or thick & tough (low SLA). The global median is about 10 mm²/mg.
Honest limits: A species-mean from pooled measurements — individual plants vary with light and site. A broad strategy signal, not a precise per-plant figure.
A recorded categorical fact: each species is tagged C3 (standard), C4 (heat/water-efficient) or CAM (succulent, night-time CO₂ uptake) — or a facultative combination. We only show a trait card for the noteworthy C4/CAM cases; C3 is the unremarkable majority, kept in the data but not surfaced as a card.
We take the plant’s U.S. county range and look up each county’s long-term climate, then summarise: native rainfall = the median annual rainfall across its counties; heat tolerance = the warm end (90th percentile) of average temperature across its range (mirroring how our cold-hardiness floor uses an extreme). Counties + medians blunt the roadside/observer bias that makes point-level climate unreliable. Needs at least five placeable counties.
Honest limits: A realized, sampling-biased niche (where it has been recorded, not its physiological optimum), and county climate is coarse — large Western counties span deserts and mountains. Derived guide, never a measured fact.
McKenzie et al. assigned each species a flower colour with a GPT-4V vision model over iNaturalist photos. We use the confident tier plus a separately-labelled lower-confidence top-up (mostly inconspicuous green/brown flowers), and render it as a small tint — never as an asserted fact, and kept out of the written synopsis.
Honest limits: AI image inference (~87% expert agreement on the confident tier); a decorative, confidence-tiered indicator, not a measured trait.
Sources for this entry (35) Open & cited
Cite this page Open data, please attribute
PlantKey’s data is open under CC BY-SA 4.0 — free to reuse and adapt, with attribution and the same licence. Photos keep their own per-image licence + credit (see Sources above).
Loading…
BibTeX
Loading…