. The Canadian field-naturalist. 1998 Douglas and Ryan: Status of the Yellow Montane Violet 493. Figure 2. Distribution of Viola praemorsa ssp. praemorsa in British Columbia. (? - extirpated sites, O - unconfirmed sites, • - recently confirmed sites) and ovules which do not open but produce seeds by self-pollination. They emerge after the petaliferous flowers have completed flowering. The extent to which V. praemorsa produces cleistogamous flowers and the importance of their contribution to seed pro- duction is not known. tained their size and plant numbers within 10% of their maximums. Limiti
. The Canadian field-naturalist. 1998 Douglas and Ryan: Status of the Yellow Montane Violet 493. Figure 2. Distribution of Viola praemorsa ssp. praemorsa in British Columbia. (? - extirpated sites, O - unconfirmed sites, • - recently confirmed sites) and ovules which do not open but produce seeds by self-pollination. They emerge after the petaliferous flowers have completed flowering. The extent to which V. praemorsa produces cleistogamous flowers and the importance of their contribution to seed pro- duction is not known. tained their size and plant numbers within 10% of their maximums. Limiting Factors The most direct and immediate threat to Viola praemorsa ssp. praemorsa is habitat destruction. This is of particular concern in the grass-dominated meadows often associated with the Quercus gar- ryana communities that are limited to the southeast- em side of Vancouver Island and some of the Gulf Islands. Both types of vegetation are believed to have been much more common before colonization by European settlers. Their destruction has continued to the present resulting in the elimination of almost all sites occurring outside parks or ecological reserves. Historically, Quercus garryana communi- ties and grass-dominated meadows have always been heavily influenced by human activity. Roemer (1972) believed that without human interference some of these stands would have eventually been replaced by Douglas-fir, Pseudotsuga menziesii, forests. The suppression of fire within the past century may also have contributed to the decrease of Viola praemorsa ssp. praemorsa populations. Most of the sites in which V. praemorsa ssp. praemorsa has been collected were likely maintained in the past as a result of periodic fires, both natural and unnatural. In the past, aboriginal peoples probably set fire to these stands to maintain them as an important habitat for wildhfe (Roemer 1972). Since that time, these sites have experienced httle disturbance, resulting in the invasion and expan
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