New York Natural Heritage Program
Back's Sedge
Carex backii Boott
Monocots

General Description [-]
A densely tufted grass-like plant, this sedge has leaves 1.3-5.4 mm wide. The leaves are up to 37 cm long and the whole plant often appears somewhat flattened. The flowers and fruits, which occur in clusters 0.7-1.6 cm long, are borne on the tips of stalks which are shorter than the leaves. The flowers and fruits are inconspicuous because they are completely concealed by leaf like structures (scales) which surround each individual flower/fruit in a cluster. The best way to look for this plant is to search for these leafy scales.

Best Life Stage for Proper Identification [-]
This species can be identified in flower although fruiting characteristics are best. A complete reproductive shoot with mature perigynia should be collected to verify the identification.

Similar Species [-]
In New York there are two (Carex jamesii and C. willdenowii) and perhaps a third (C. juniperorum) species that are somewhat closely related and similar morphologically. Carex backii can be distinguished from all three by its wider pistillate scales (2-6.5 mm wide compared to 1.6-2.22 mm for C. willdenowii, 1.4-3.0 mm for C. jamesii, and 1.2-3.0 mm for C. juniperorum) which completely conceal the perigynia in C. backii as compared to not concealing the perigynia in these other species. These scales and particularly the upper scales have narrow hyaline or green margins in C. backii as well as C. juniperorum but have broad hyaline margins in C. willdenowii and C. jamesii. Carex backii also has 2-3 staminate flowers per terminal spike as compared to 3-29 for C. willdenowii, 3-13 for C. jamesii, and 5-21 for C. juniperorum. In addition, C. backii has clavate, minutely papillose stigmas as compared to filiform, strongly papillose stigmas of C. willdenowii, C. jamesii, and C. juniperorum.
Back's Sedge Images
click to enlarge
The Best Time to See
The species is in fruit from late May to mid July although fruits are shedding by the end of this season making identification more complicated at this time. Surveys for this species should be done from late May through June.
J F M A M J J A S O N D
Fruiting
The time of year you would expect to find Back's Sedge fruiting (green shading) in New York.