Aulacomnium palustre

On a walk along the ski trails at Stake Lake just after much of the snow had melted I was looking for things to photograph. In a moist forested area next to the trail I came upon a patch of moss often called glow moss because of its bright green colour. However, it was looking more orange than bright green after sitting under the snow for a few months.

But you can see new green shoots emerging that give this species of moss it’s characteristic name.

This is what the moss in the above photo will look like a couple of weeks later – a nice bright green colour.

Glow Moss (Doug Smith)

The following photo is of a mature shoot showing the characteristic green leaves with a white midrib that are characteristic of glow moss.

The leaves of glow moss are one-cell layer thick and the individual cells are often square or rounded and each cell has a single bump on the cell wall that you can see in some of the leaf cells in the following photo of a closely related species, Aulacomnium androgynum, that is much smaller in size and grows on decayed wood.

Like most mosses, glow moss produces capsules containing spores that are often on stalks that elevate the capsule above the leaves. Here the capsule has not opened yet to release the spores – the capsule opening is still covered by the capsule lid that is called an “operculum”.

Some species of Aulacomnium including glow moss also produce specialized asexual reproductive bodies called gemmae on small naked stalks that emerge from the tips of some shoots as shown below for Aulacomnium androgynum.

This is what a single gemma looks like under the microscope. It consists of a few cells that will eventually grow to produce a new plant.

Glow moss is a very widespread species that is typically associated with moist to wet forested areas and some wetlands at higher elevations around the Kamloops area. It is often easily recognized in the summer and fall from the bright green colour of the shoots that seem like they would glow in the dark (but they don’t!).