. The Canadian field-naturalist. Figure 1. Habit, inflorescence and achene of Scirpus verecundus. Drawn from Crins 6286, Sutherland & Varga; Crins 6312 & Dyer; Crins 6475 (relevant specimens in TRTE) by Lesley Bolm. forest canopy has developed. It shows the characteristic features of an anemophilous (wind- pollinated) plant, lacking showy perianth and nectaries and having relatively large, well exserted stamens and stigmas. Its flowers are protandrous (anthers emerging beyond scales before receptive stigmas), but the extent of outcrossing must be limited by the low stature of the plant
. The Canadian field-naturalist. Figure 1. Habit, inflorescence and achene of Scirpus verecundus. Drawn from Crins 6286, Sutherland & Varga; Crins 6312 & Dyer; Crins 6475 (relevant specimens in TRTE) by Lesley Bolm. forest canopy has developed. It shows the characteristic features of an anemophilous (wind- pollinated) plant, lacking showy perianth and nectaries and having relatively large, well exserted stamens and stigmas. Its flowers are protandrous (anthers emerging beyond scales before receptive stigmas), but the extent of outcrossing must be limited by the low stature of the plants and the irregular terrain in which the populations occur. Seed dispersal is well under way by late July and is virtually complete by early to mid-August. By late July, the leaves and culms become matted on the forest floor. This feature undoubtedly facilitates local dispersal and suggests a mechanism by which dense colonies of clumps could become established. If this mode of colony establishment is correct, then adjacent clumps must be closely related genetically. Seed set is extremely high, in spite of this presumed low genetic diversity within populations. Population Size and Trends Seven populations of S. verecundus arc known in ( anada. These occur in two areas separated by \!_^'^ i / 1^â â .^LX-^J" i i» 1 oc^^^a^-^ :\j_^ i i a V, r&^ AV~M' ^\r^i&r^^. y^isy - i ° ... ^r i. i» Figure 2. Distribution of Scirpus verecundus in Ontario. approximately 90 km (east Toronto and west Hamilton). Within these areas, the populations are relatively close to one another. In the Rouge River valley of Toronto, the two populations are less than 1 km apart. The five populations in Cootes' Paradise (Royal Botanical Garden property), Hamilton, are all within 2 km of each other. Due to the colonial nature of this plant, it is difficult to estimate the number of plants contained within each population. The clonal nature of the species, as well as its dispersal biolo
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