Juncus effusus (Soft rush)

Juncus effusus L.

Soft rush, common rush

Kingdom	Plantae	Plants, but not fungi, lichens, or algae
Subkingdom	Tracheobionta	Vascular plants—plants with a “circulatory system” for delivering water and nutrients
Division	Magnoliophyta	Flowering plants, also known as angiosperms
Class	Liliopsida	Monocots (plants with a single seed leaf); includes the lily family
Subclass	Commelinidae	Dayflowers and spiderworts, and several others
Order	Juncales	Rushes, sedges, and other grasslike plants
Family	Juncaceae	Rush family
Genus	Juncus	Possibly from Latin jungere, “to join or bind,” because the stems were used for binding
Species	effusus	"Loosely spreading, straggling, spread out" (from Stearn's Botanical Latin)

About plant names...

Soft or common rush is native to Eurasia, North America, Australia, and New Zealand. It is at home in acidic, wet soils, such as pond or swamp edges. The attractive-looking clumps are sometimes used in landscaping.

Plants: Soft rush reaches 24-48" (60-121 cm) in height, growing in clumps (“tussocks”) 24-48" (60-121 cm) around. Individual stems resemble grass from a distance, but up close, they are smooth and round, filled with a light pith, and soft to the touch. At the base of each stem there is a dark ”basal sheath” 2-3" (5-7.6 cm) long.

Leaves: A reddish or brown sheath at the bottom of each stem.

Flowers: The most notable characteristic is the flower clusters, with 30-100 flowers, which stick out sideways from partway up the stem, looking rather lopsided. Actually, the flowers are at the stem tips, but a bract (specialized leaf) continues upward, looking like a continuation of the stem. Tiny, barely noticeable flowers are yellowish-green to pale brown.

Fruits: Brown oval capsules about ¹/₁₆-⅛" (2-3.5 mm) long, which split open into three parts, releasing tiny seeds about ¹/₃₂" () in size. Each seed is long, flattened, roughly elliptical, and brown.

Online References:

Juncus effusus at Illinois Wildflowers

Juncus effusus on CalPhotos

Juncus effusus on floridata.com

Juncus effusus on Perry’s Perennial Pages at the University of Vermont

Juncus effusus on the USDA Plants Database

Juncus effusus at the Missouri Botanical Garden

Juncus effusus on Plants for a Future, a resource and information centre for edible and otherwise useful plants

Juncus effusus from the Jepson Manual

Juncus effusus on eFloras

7/15/2020 · Cathance River Nature Preserve Trails, Highland Green, Topsham, Maine
≈ 12 × 8" (31 × 20 cm)

6/8/2012 · Townsend Wildlife Management Area, Townsend, Massachusetts
≈ 4 × 6" (10 × 15 cm) ID is uncertain

6/20/2012 · Nashua River Rail Trail, Groton Center, Groton, Massachusetts
≈ 8 × 5" (19 × 13 cm) ID is uncertain

6/8/2012 · Townsend Wildlife Management Area, Townsend, Massachusetts
≈ 6 × 9" (14 × 22 cm) ID is uncertain

Juncus effusus description by Thomas H. Kent, last updated 14 Aug 2021.

6/29/2014 · Mount Agamenticus, York, Maine
≈ 6 × 9" (15 × 23 cm)

6/22/2010 · Nashua River Rail Trail, Ayer, Massachusetts
≈ 7 × 4½" (17 × 11 cm)

7/15/2020 · Cathance River Nature Preserve Trails, Highland Green, Topsham, Maine
≈ 4½ × 7" (11 × 16 cm)

6/8/2012 · Townsend Wildlife Management Area, Townsend, Massachusetts
≈ 3½ × 5" (9.2 × 13 cm) ID is uncertain

6/22/2010 · Nashua River Rail Trail, Ayer, Massachusetts
≈ 9 × 6" (22 × 14 cm)

6/20/2012 · Nashua River Rail Trail, Groton Center, Groton, Massachusetts
≈ 11 × 7" (27 × 18 cm) ID is uncertain

Range: Zones 4-9:

About this map...