Spikes:

A spike at the top of the stem with 3 to 13 staminate (male) flowers at the tip and pistillate (female) flowers below (androgynous), the staminate portion up to 14 mm (to ~½ inch) long. At the base of each pistillate flower is a bract, the lowest one in the spike largest and leaf-like, to 5 cm (2 inches) long but not (much) wider than the spike, the uppermost bract much smaller and more scale-like. One to 4 additional spikes on slender, flexible stalks arise from or near the base of the stem; these are androgynous or all-pistillate.

Leaves and stems:

Four to 6 leaves are attached near the base, each up to 15 inches long, 2 to 3.5 mm wide, longer than the flowering stems, hairless, mostly flat. Stem leaf sheaths are whitish and tightly wrap the stem. The ligule (membrane where the leaf joins the sheath) is longer than wide.

Bases are wrapped in a dark cinnamon-brown sheath that is not fibrous. Stems are slender, erect to ascending, 3-sided, varying in length, up to 12 inches tall at maturity but remain shorter than the leaves. Plants are densely clump-forming in large, rounded mounds and not colony forming.

Fruit:

Fruit develops in mid to late spring, the spike forming a cluster of seeds (achenes), each wrapped in a casing (perigynium), subtended by a scale; staminate scales may persist on the terminal spike. Each spike contains 1 to 4 fruits, erect to ascending and overlapping.

Pistillate scales are narrowly lance to awl-shaped, tapering to a pointed tip, that of the lowest perigynia largest, green and leaf-like but with translucent edging near the base, the uppermost more scale-like and about as long as or shorter than the perigynia. Perigynia are 4.4 to 7.2 mm long, 1.9 to 2.4 mm wide, 2-veined, green to bronzy when mature, urn-shaped to oval-elliptic, round in cross-section, tightly wrapping the achene, abruptly tapered at the spongy base when mature, abruptly tapered at the tip to a toothed beak 1.6 to 3.8 mm long. Achenes are 2 to 2.6 mm long, nearly round in cross-section, rounded at the tip, abruptly tapered at the base, brown at maturity.

Notes:

Carex jamesii is a rare sedge in Minnesota, where it reaches the northern edge of its range, found primarily in rich, deciduous forest, shady ravines, and the base of shady bluffs. It was first discovered in Beaver Creek Valley State Park in 1984 and shortly after in Forestville SP. According to the DNR, subsequent biological surveys located few populations, and its forest habitat is at risk from a variety of factors, including logging, invasive species, and development (same sad story we've heard many times before). It was listed as a state Threatened species in 1996.

Carex is a large genus, with over 600 species in North America and 150+ in Minnesota alone. They are grouped into sections, the species in each group having common traits. Carex jamesii is in the Phyllostachyae section; some of its common traits are: clump forming, basal sheaths brown and not fibrous, leaves V-shaped in cross-section when young, leaves hairless and much longer than fruiting stems, 1 to 5 spikes, terminal spike with staminate flowers at the tip (androgynous), lateral spikes stalked and androgynous or all-pistillate, lowest sometimes at or near the plant base, perigynia beaked and hairless, 2-veined or obscurely veined, beak toothless, lowest pistillate scales green and leaf-like, achenes 3-sided with 3 stigmas. The leaf-like pistillate scales are unique to species in this section.

Carex jamesii is one of the three members of the Phyllostachyae section in Minnesota and is distinguished from other Carex species by the combination of: densely clump-forming, largest leaves to 3.5 mm wide and much longer than the flowering/fruiting stems, stems of varying lengths, the basal spikes on long flexible stalks, terminal spike with erect, leaf-like bracts not (much) wider than the perigynia, perigynia 4.4 to 7.2 mm long with an abrupt taper to a beak up to half as long as the perigynia. Most similar are Carex backii and Carex saximontana, both of which have a much shorter staminate portion on the terminal spike (less than 4mm), the largest leaves are broader (5+mm), less densely clump-forming, and basal spikes are on stiffer, more erect stalks.