Enhancements to the VASCAN Checklist Builder

Tuesday, 15 April 2014

The Vascular Plants of Canada website received some updates to its checklist builder today, making it easier to use. Provinces and Territories on the map are now clickable, the main occurrence options were reworded, and treatment of Saint Pierre and Miquelon and Greenland is now more explicit.

Saint Pierre and Miquelon & Greenland

The Vascular Plants of Canada treats Saint Pierre and Miquelon and Greenland in a special way. As you may have noticed, they are included in the Atlantic and Arctic regions, respectively. However, clicking “Canada” at the top of the region list does not include either Saint Pierre and Miquelon or Greenland.

There is a new checkbox entitled, “include plants that may also occur in Greenland or Saint Pierre and Miquelon” at top of the region selector. Should your region selections include Atlantic or Arctic Provinces/Territories, this checkbox becomes important, depending on your chosen occurrence option(s) and chosen distribution status(es). For example, if you were interested in the vascular plants that are native to and only occur in Newfoundland and Labrador but did NOT select “include plants that may also occur in Greenland or Saint Pierre and Miquelon”, your list would exclude species that additionally occur in either Saint Pierre and Miquelon or Greenland, a total of 24 species. Checking “include plants that may also occur in Greenland or Saint Pierre and Miquelon” would produce a list of 27 species. The additional 3 hybrids/species are Alchemilla alpina Linnaeus, Diphasiastrum ×takedae Y.A. Ivanenko, and Atriplex nudicaulis Boguslaw, which are native to Newfoundland and Labrador, but are ALSO native to either Greenland or Saint Pierre and Miquelon.

Occurrence Options

Plants that occur [ in any of / in all of / only in / in all of and only in ] are the new occurrence options.

Selecting the distribution status native, introduced, ephemeral, doubtful, extirpated, or excluded at the bottom of the regions selector is also very important to establish the scope of the filter. When more than one distribution status is selected, these are considered “OR” selections. In other words, choosing both “native” and “extirpated” under distribution status would produce a list of taxa that are considered “native” OR “extirpated” among all selected Provinces and Territories – VASCAN considers a distribution status to be Province- or Territory-wide. It usually helps to think of the significance of these distribution statuses when just one is chosen. Therefore, examples provided below will use just one of the six statuses.

What is the significance of the logic behind the four main occurrence options?

In Any of

Choosing this option will produce a list of taxa each with at least one of your chosen distribution statuses in at least one of your chosen Provinces/Territories. If you were interested in finding extirpated taxa in any of the Prairie provinces, you would use this option. This would show you that Sporobolus compositus (Poiret) Merrill var. compositus, the rough dropseed [PHOTO], has been extirpated from Saskatchewan, its presence is doubtful in Manitoba, it is absent from Alberta and yet it is native to the much of the rest of Canada.

In All of

Choosing this option will produce a list of taxa each with at least one of your chosen distribution statuses in all of your chosen Provinces/Territories (but not exclusively so). Unselected Provinces/Territories could also have the distribution statuses you selected. For example, you may be interested in producing a comprehensive list of species that are native to Labrador and the island of Newfoundland. Making such a list should not exclude species that are native to other Provinces or Territories in Canada.

Only In

Choosing this option will produce a list of taxa each with at least one of your chosen distribution statuses exclusive to all of your chosen Provinces/Territories. All other Provinces/Territories must have other distribution statuses than the one(s) you selected. For example, you may wish to create a list of species that are native to Greenland or Nunavut, but native to nowhere else in Canada. This filter would show you that there are 64 such example, including the alpine fleabane, Erigeron alpiniformis Cronquist, a delicate herb with pink/purple flowers.

Holotype of Erigeron alpiniformis Cronquist © Smithsonian Institution, National Museum of Natural History, Department of Botany

In All of and Only In

Choosing this option will produce a list of taxa with at least one of your chosen distribution statuses exclusive to all of your chosen Provinces/Territories. If you were interested in finding taxa that are considered introduced to all Atlantic Provinces but not in other Provinces or Territories, you would use this query. For example, Symphoricarpos albus (Linnaeus) S.F. Blake, the common snowberry is native to most of Canada, but considered introduced to the island of Newfoundland, Prince Edward Island, Nova Scotia, and New Brunswick.

Symphoricarpos albus (Linnaeus) S.F. Blake, the common snowberry © H. Zell

We hope these new adjustments clarify the logic behind the Vascular Plants of Canada checklist builder and make it easier for you to use. If you have other examples of how this interface led you to new understanding and appreciation for vascular plant species distributions in Canada, please let us know in the comments.