Diario de rambryum

Conglomerates are a type of sedimentary rock made up from peices of other rocks. With the obligatory reference to this Beavis and Butthead clip, I can't emphasize enough the satisfaction I get seeing a rock made out of rocks. Sometimes, the rock is made out of rocks that themselves are made out of rocks. I don't know what the record is, but locally both the Jackass Mountain Conglomerate (around Lilloett and southwards) and the various coarser units of the Nanaimo Group (which outcrops all along the Salish Sea) offer lots of ponderous exposures.

If you are interested in bryophytes and lichens, there are few substrates that show as much variation. Because of the shapes of both the cobbles and the concavities left behind when said cobbles weather out, you get tremendous variation in aspect over a matter of inches. Furthermore, the cobbles that make up the conglomerate can be both texturally and compositionally heterogenous. As a cherry on top, the intersticies between the cobbles, known geologically as "the matrix", can also be compositionally and texturally heterogenous.

On Denman Island there is a group of three massive conglomerate boulders called "Triple Rock". You can see them on a satellite photo here. They are presumably remnants or erratics from the submarine channel deposits of the Nanaimo Group, perhaps dropped as the ice sheet melted out in the area roughly 20,000 years ago. This conglomerate is made of cobbles that vary from volcanic basalts to intrusive granites to metamorphic quartzites and even calcareous nodules, the ages of the individual cobbles varying from ~80 million years old to roughly 1,500,000,000 million years old. The matrix in this case is a calcite-cemented sand, giving the rocks a basic quality that leads to unexpected bryological surprises-- things typical of Garry Oak bark or limestone make cameo appearances.

What fallows are all the mosses I could kick up on these conglomerates. If you are ever on Denman, stop by and try and add to the list.

Moving closer to the darkest day of the year, certain habitats become off limits. The rivers are too high, the mountains are under snow and ice, the forest sloughs flooded. On a day like today, even the tides are prohibitively high for looking at coastal outcrops. It seems human environments get extra attention in the winter because of their ease of accessibility and the often unique assemblages of bryophytes that tend to gather is these disturbed places.

Chances are you are never far from a quarry pit where sand and gravel have been excavated for road bed, concrete, foundational materials and landscaping. In the summer, these tend to be dusty places, but in the winter in SW British Columbia, they saturate as the water table rises. The banks from which materials have been excavated can seep, as do the track margins along which the excavators excavate and the aggregate trucks haul out. The combination of mineral soils and saturation seems to promote the growth of a predictable community. What follows is an incomplete list (and subsequent images) of the taxa you might find in this region along quarry edges. I am ordering the list from Dryest to Wettest-- imagine the driest ones being on the upper lip of seasonal pooling of water, whilst the wettest ones are saturated for much of the year. Those without photos below are linked to iNat taxon pages.

Pogonatum urnigerum (dry gravels and sands)
Polytrichum juniperinum (drier gravels and sands)
Racomitrium elongatum (drier sands)
Ceratodon purpureus (finer soils, more seasonally saturated)
Philonotis fontana or Philonotis capillaris (seeping finer mineral soils)
Bryum/Gemmabryum barnesii (flat, exposed, saturated and finer mineral soils)
Pleuridium acuminatum (flat, exposed, saturated and finer mineral soils)
Tortula truncata (flat, exposed, saturated and finer mineral soils)
Riccia sorocarpa (flat, exposed, saturated and finer mineral soils)

One of the recurrent issues I have when trying to photography informative characters in small organisms is capturing in an image the level of detail I can see with my eyes. With the twirl of the stage knobs and the focus knobs and the diaphragm, I can see leaves from base to tip through different cell layers with the required levels of light. But when you take a photograph, you only capture one frame in one plane.

Modern microscopy imaging setups have been able to deal with this issue with automated stacking and tiling that is integrated with the camera and its requisite software. For the homebrew microscopists, it gets a little trickier absent a very expensive microscope. To that end, i've recently discovered a great peice of cross-platform open-source software called "Hugin". While its meant for home-stitching of panoramas from image sequences, it is actually amazing for stitching together microscope photos. Not only does it stitch together in the X & Y planes, it also can do a version of focus stacking by stiching between optimal sections of each photo. This has allowed me to shoot entire leaves in focus, both in surface veiw and in cross section. I've pasted a recent observation of Pogonatum contortum as an example.

Another tool that I have found useful for about 20 years now is ImageJ. Developed by the US NIH for analytical tasks generally related to cell imaging, it has a deep library of plugins and add ons that make it very helpful. I use it to measure things like cell dimensions, variation in spore size, surface area of leaves and other tasks that used to take way more work. It has a focus stacking module that is ideal for imaging spores. @david1945wagner has an incredible PDF linked at his website that goes through lots of tips and tricks for home microscopy. Amongst them is the construction of a a tool to standardize increments through the focus plane to make for optimum results when you feed them into stacking software.