Arctous (Arctostaphylos) rubra

Submitted by cohan on Tue, 11/13/2012 - 00:38

I was about to start a thread for Arctous (Arctostaphylos) rubra, but I see we don't have an Ericaceae section yet.. perhaps someone can rectify that? ;) [Your wish is my command, Cohan! :) - Moderator]
meantime a few pics- I will eventually show the plants in several seasons- all equally charming...
Here it is on June 26, 2010. this is the same site near the Athabasca Glacier (Columbia Icefields site on the Icefields Parkway, Alberta).
The first couple show the Arctous with one of the white flowered Dryas discussed earlier; (these shots should be a little darker, but not as much as you think- at this time of year, many of the Dryas have not made a lot of new growth and mats appear largely grey)..

Third shot is with Hedysarum boreale in flower, and a low but not prostrate Salix sp/willow- maybe about a foot tall..

Last couple show the Arctous with an Antennaria sp..

I'd have to review all my photos to be sure, but I think the Arctous at this site are all/mostly on fairly low/flat areas between the mounds and ridges of glacial deposit, and also, I think on the gentle slope a little farther back which has clearly been vegetated much longer than these gravelly rocky zones- though even these have been free of the glacier for many decades to well over a century. In this zone there would be little to no humus apart from what these subshrub mats have created themselves. I also assume these areas are generally fairly moist, though I think this summer I saw the area looking dryish for the first time (I mean first time I saw such a thing, which is not saying that much) though that was likely superficial..
More to come..


Submitted by cohan on Wed, 11/21/2012 - 11:47

If I have it straight, only rubra occurs in Alberta. Its certainly common at this site, I haven't seen much in other places, but I think that's just because I haven't been in the right spots.. certainly nothing as common as Arctostaphylos uva-ursi (correction!) which is everywhere from the drylands to altitude..

Submitted by cohan on Wed, 11/21/2012 - 23:48

Lori wrote:

I think there's a typo in your last post, Cohan?  Where it refers to Arctous rubra as being "everywhere", I think you may have meant to say Arctostaphylos uva-ursi.   :)

By the way, I found this site (and must bookmark it)... looks interesting:;jsessioni...

Oops! absolutely right, thanks!
Interesting map- I found all those blanks a bit confusing at first, though interesting- I guess those are places that were specifically checked for the species in question or had species catalogued and it was not found? I'm not quite sure if any of those sites correspond to where I've seen it (doesn't seem like it)- I find it hard to judge locations on these site maps with no place names or roads shown (as with Flora of Alberta, also) -it would be nice to have large versions as transparencies  that could be overlaid on detailed maps...

Submitted by Lori S. on Thu, 11/22/2012 - 19:56

It's a grid laid out with a dot at the center of each grid area.  Grid areas that were surveyed (one location or more within that grid area, presumably), and the species not found there, are marked with yellow dots.  Grid areas that were surveyed where the species was found are marked with yellow dots with red centers.  Neat!

Submitted by cohan on Fri, 11/23/2012 - 00:22

Yeah, I'll have to do some more looking around on that site .. I know the maps in Flora of Alberta don't show a lot of things in my area that in fact are, but I assume that's just gaps in areas that happen to have been botanised- don't imagine there's a lot of it going on around here-- all private land..

Submitted by Tim Ingram on Fri, 11/23/2012 - 03:07

Cohan - those little communities of plants set around Arctous rubra are just delightful. Dwarf ericaceae are a group I know little about, living in the wrong place with the wrong soil to grow them well, but I would very much like to learn more of them.

Submitted by Lori S. on Fri, 11/23/2012 - 23:25

cohan wrote:

.. I know the maps in Flora of Alberta don't show a lot of things in my area that in fact are, but I assume that's just gaps in areas that happen to have been botanised- don't imagine there's a lot of it going on around here-- all private land..

The preface to Flora of Alberta (page viii) explains that the range maps are based on collections from the National Museum (Ottawa), the Department of Agriculture Herbarium (Ottawa), the major herbaria in Alberta and some "well-authenticated literature and sight records" with each dot on the map referenced to herbarium, locality  and collector.  I'm pretty sure the dot maps are meant to be generalized.

However, a complete, thorough sampling does seem more clearly to be the possible, eventual premise behind the biodiversity maps I linked, in that these show sites that were visited and of those, where species occurred and also where they didn't.

Submitted by cohan on Sat, 11/24/2012 - 18:59

Thanks, Tim- I'll show those communities in more seasons when I get a chance- I have photos from spring and fall also, and I'll link to other postings with more of the other plants there..

Lori- I do realise there is no way the range maps in F.of A. can be totally complete (it would be interesting to know more about the sources, how sites for sampling were chosen etc, but I expect that would be volumes of reading even if one had access)..

The other project will be interesting to keep an eye on..

Submitted by cohan on Mon, 11/26/2012 - 12:14

Some more images, this is from May 31, 2011; At this time, snow has receded from most of the open areas at this site (still near the Athabasca Glacier) though there were still some snowbanks around and melt pools. The Arctous is at various stages of emergence, none fully leafed out, but some quite advanced, others just starting. Flowering appears to start before the leaves, and continues with young leaves. I believe this species can have above ground stems or underground, I haven't noticed above ground stems here, but I have not dug into the leaf litter..
Here's an album with more photos, showing other plants in the area etc..

1 shows part of my shoes, giving some scale..
2 with Dryas and Hedysarum
3 flowers
4 large patch with flowers
5 flowering plants
6 large patch with flowers
7 with fancy rock
8 flowering plants
9 flowering plants

Submitted by cohan on Wed, 11/28/2012 - 00:00

This section is around the moraines not too far from the glacier(though still at least many decades out of the ice); the heaviest plant cover is in the sheltered areas between ridges, and the Arctous is mostly on these flats - not always in the most sheltered places, but not on the sides or tops of the piles of rock, gravel etc. These shots show some of the more isolated patches, but they do also grow with Dryas, Salix, Arctostaphylos etc and some forbs grow through the Arctous- notably Anemone parviflora as I have shown elsewhere.
Yes, the rocks and gravel are still very prominent in this landscape, one of the things I like about it :)