The genus Carex of Renfrew County:
A comparative study

By Grant A. Bickel, 2020

Carex richardsonii R. Br., Richardson’s Sedge (Section CLANDESTINAE)

Carex richardsonii is a rare species in Renfrew County found in alvars and limestone plains. The prominent reddish brown bracts and sheaths (Figures 3, 4 and 5) distinguish this species from the similar looking species in Section ACROCYSTIS.

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Achenes, perigynia and scales of Carex richardsonii

Figure 1. Achenes, perigynia and scales.
Habit of Carex richardsonii

Figure 2. B&W scan of specimen showing habit.
Terminal inflorescence of Carex richardsonii

Figure 3. Terminal inflorescence.
Lateral inflorescence of Carex richardsonii

Figure 4. Lateral inflorescence.
Basal sheath of Carex richardsonii

Figure 5. Basal sheath of culm.
Habit of Carex richardsonii

Figure 6. Habit.
Inflorescence of Carex richardsonii

Figure 7. Inflorescence.
An occurrence map of Carex richardsonii in Renfrew County

Figure 8. Occurence map for Renfrew County and surrounding area.
Accession records for specimens from Renfrew County
Accession # Collector Date
DAO 859633 A. Ward, S. Kyte, G. Gregorich, P.M. Catling & G. Mitrow 2011-June-02
DAO 888120 S.R. Brinker, M.J. Oldham & D. Coulson 2010-June-22
DAO 871909 G.A. Bickel 2005-June-03
DAO 542170 D.F. Brunton & K.L. McIntosh 1986-May-25
CAN 487083 S.J. Darbyshire & W.J. Crins 1983-June-05