Wild Species 2015: plant kingdom
Bryophytes refer to the phyla Marchantiophyta (liverworts), Bryophyta (mosses) and Anthocerotophyta (hornworts). They are simple plants that typically grow low to the ground in moist environments. Lacking true roots and vessels, they absorb water and nutrients directly across their surface. This limits their size, as without woody tissue they don’t have the rigidity to grow tall. When dry, growth and metabolism stop until moisture revives them. They can reproduce asexually when water is scarce, or sexually by producing spores that are usually wind dispersed. Only a small fraction of spores land in conditions suitable for growth. Some species counter this by producing many millions of spores, while a few, such as the dung mosses, attract flies to deliver spores directly to their favoured growth medium: excrement. Bryophytes are ecologically significant, particularly in boreal and western coastal forest, alpine areas, and tundra. They colonize bare rock and affect water runoff, nutrient cycling, soil formation, and ground temperature. Sphagnum mosses are harvested on an industrial scale in several parts of Canada and used as soil amendments, chemical absorbent, wrapping material for plants, and component of menstrual pads. Canadian bryophyte distribution is understood at a general but not at a detailed scale, and mosses are better studied than either hornworts or liverworts. Threats to bryophytes include habitat loss and climate change.
There are 1375 known species of bryophytes in Canada (Figure 6). Many species are apparently secure or secure (47%). There are two species that are presumed extirpated, one species that is possibly extirpated, 75 species that are critically imperiled, and 85 species that are imperiled. Of these 163 species, 84 have only a small part of their range in Canada (10% or less) and 64 are intermediary (from 11% to 74%). However, 15 species have 75% or more of their range in Canada. Among those, eight species are thought to be endemic to Canada: Anastrophyllum tenue, Calliergon orbicularicordatum, Frullania hattoriana, Neomacounia nitida, Scapania diplophylloides, Seligeria careyana, Sphagnum venustum, Trematodon montanus. In total, 27 species have a high priority score (between 1 and 5). We also identified nine species that are exotic at the national level. We do not have enough knowledge on 398 species to give them a rank other than NU or NNR. No species of bryophytes are considered migratory.
The mosses were assessed in the Wild Species 2010 report. Since then, 305 species had a change in their status at the national level. A total of 49 species had an increased level of risk, 25 species had a reduced level of risk, and 158 species were changed from or to ranks U, NR, NA. Also, 52 species have been added to the list and 21 have been deleted from the list. Most of the changes (72%) are due to a procedural change.
Vascular plants refer to the phylum Tracheophyta. Plants are critical to all life. They provide oxygen, food, and wildlife habitat. They regulate the climate, create soil, improve air and water quality, and reduce erosion. Vascular plants have roots, leaves, and vessels (i.e. a vascular system) to transport water and nutrients. They include plants with spores such as ferns, and cone-bearing plants like pine trees, but the vast majority are flowering plants (e.g. grasses, orchids, maple trees). To reproduce, they use the wind or animals to carry pollen from male to female flower parts, and flowers have developed showy petals, nectar, and alluring scents to attract pollinators. Seeds in turn may be wind-dispersed or may be enclosed in fruit to entice animals to eat and spread them. In nutrient poor wetlands, some species have gone carnivorous, and actually eat insects. The distribution and status of vascular plants is generally well known, particularly for southern Canada. Most current research focuses on species significant to agriculture, forestry, or medicine. Habitat loss, habitat degradation and invasive species are the major threats to vascular plants. Over-harvesting is a concern for some species, particularly those with high medicinal or aesthetic value.
There are 5211 known species of vascular plants in Canada (Figure 7). The majority of these species are apparently secure or secure (52%). There are 26 species that are presumed extirpated, 24 species that are possibly extirpated, 315 species that are critically imperiled, and 325 species that are imperiled. Of these 690 species, 396 have only a small part of their range in Canada (10% or less) and 240 are intermediary (from 11% to 74%). However, 54 species have 75% or more of their range in Canada. Among those, 42 species are thought to be endemic to Canada: Quebec Rockcress (Boechera quebecensis), False Northwestern Moonwort (Botrychium pseudopinnatum), Fernald’s Braya (Braya fernaldii), Long’s Braya (Braya longii), Hairy Braya (Braya pilosa), Newfoundland Chickweed (Cerastium terrae-novae), Elkwater Hawthorn (Crataegus aquacervensis), Dark Green Hawthorn (Crataegus atrovirens), Enderby Hawthorn (Crataegus enderbyensis), Orbicular-leaved Hawthorn (Crataegus orbicularis), Adams Creek Hawthorn (Crataegus rivuloadamensis), Battle Creek Hawthorn (Crataegus rivulopugnensis), Red Bracteole Hawthorn (Crataegus rubribracteolata), Sheila Phipps’s Hawthorn (Crataegus sheila-phippsiae), Shuswap Hawthorn (Crataegus shuswapensis), Macoun’s Cryptantha (Cryptantha macounii), Mackenzie Hairgrass (Deschampsia mackenzieana), Caswell’s Draba (Draba caswellii), Cayouette’s Draba (Draba cayouettei), Frankton’s Draba (Draba franktonii), Kluane Draba (Draba kluanei), Puvirnituq Mountain Draba (Draba puvirnituqii), Dense Draba (Draba pycnosperma), Taylor’s Draba (Draba taylori), Yukon Draba (Draba yukonensis), Ojibway Waterwort (Elatine ojibwayensis), Peace River Fleabane (Erigeron pacalis), Queen Charlotte Avens (Geum schofieldii), Gaspé Saxifrage (Micranthes gaspensis), Nymphaea loriana, Mackenzie River Yellowcress (Rorippa crystalline), Seashore Stitchwort (Sabulina litorea), Green-scaled Willow (Salix chlorolepis), Barrens Willow (Salix jejuna), Blanket-leaved Willow (Salix silicicola), Turnor’s Willow (Salix turnorii), Tyrrell’s Willow (Salix tyrrellii, Mount Albert Goldenrod (Solidago chlorolepis), Gillman’s Goldenrod (Solidago gillmani), Solidago jejunifolia, Gulf of St. Lawrence Aster (Symphyotrichum laurentianum), Gulf of St. Lawrence Dandelion (Taraxacum laurentianum). In total, 138 species have a high priority score (between 1 and 5). We also identified 1315 species that are exotic at the national level. We do not have enough knowledge on 47 species to give them a rank other than NU or NNR. No species of vascular plants are considered migratory.
All the vascular plants were assessed in the Wild Species 2010 report. Since then, 949 species had a change in their status at the national level. A total of 227 species had an increased level of risk, 195 species had a reduced level of risk, and 85 species were changed from or to ranks U, NR, NA. Also, 271 species have been added to the list and 171 have been deleted from the list. Most of the changes (35%) are due to an improved knowledge of the species.
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