Freitag, 28. Februar 2014

Plant of the Day (February 28th, 2014) - Bryum argenteum Hedw.

Today's “Plant of the Day” is Bryum argenteum Hedw. from the Bryaceae family. In English, the species is known as “Silver moss”. The German name is “Silbermoos” but “Silber-Birnmoos” is also very common.

1) Description

B. argenteum grows in dense and compact turfs. The cylindrical shoots of the Gametophyte are mostly around 1 centimeter long, so it isn't a very tall moss. However, these shoots are densely covered with small “leaves” (we call them leaves but in fact, mosses have no real leaves like the higher plants). These leaves are tiny and only between 0.5 and 1.25 millimeters long.

B. argenteum -between to concrete plates

However, the leaves are a distinctive character of identification for this species. There are two kinds of them: the basal leaves of the shoot and the leaves, which are located at the top of each shoot. The basal leaves are more spade-shaped, while the other leaves are more round but with a significantly narrowed tip. This tip has no chlorophyll and as a result a silver to white color, when dry. 

B. argenteum - habitus; you can see the silver tips
In both cases, the leaves are concave curved and have a leaf rib on their dorsal site. However, these rib goes not to the tip but ends in the middle of the leave blade. Both kind of leaves lie directly on the shoot like scales. However, protruding leaves are also possible; especially in the dry state.

 B. argenteum - the distinctive, silver shimmer

By the white color of the leaf tip, which I've described above, the stocks of B. argenteum shimmer silver, when dry. This is also the reason for the name of the species (“Argentum” is Latin and means “silver”).

The Sporphyte of B. argenteum is kept simple with a Seta and a capsule, which contains the spores. The Seta is about 1 centimeter long. The capsules at the end are pendulous or nearly horizontally. They are produced between autumn and spring.

2) Distribution

B. argenteum is a cosmopolitan and widely distributed. It benefits largely by the anthropogenic influence, because it prefers nutrient rich places to grow. Thereby, the species can be found nearly everywhere like ruderal wastelands, railway line or even in the cracks between concrete slabs. 

B. argenteum - is widey distributed in urban areas
As with the most species, B. argenteum can grow even under the most adverse circumstances and has also the ability to endure longer periods of dryness.

Mittwoch, 19. Februar 2014

Cryptogams of the Ruhr-University Bochum 2014

As in the years 2012 and 2013, I participated in a Field Trip to the Ruhr-University, which looks for Moses, Lichens and Fungi, which grow in the urban surrounding of the campus. So, it's also time for a new report about this field trip. Unfortunately, I didn't made a report in 2013, because there was to many snow and so I hadn't enough lichens or mosses for an interesting report. So, the temperate winter, which we have in Germany this year, may not be good enough for winter sports but it's ideal for some kind of hobby Lichenology. The Field Trip was organized by the “Botanischer Verein Bochum e. V.”, of which I'm a member.

1) The areal

The field trip is part of a series of field trips, which examine the population and diversity of lichens and mosses at the Campus of the Ruhr-University in Bochum, Northrhine-Wesphalia. It started three years ago in 2011 and each year, another part of the Campus was examined. This year, the field trip takes a closer look at a small area in the south west of the University. It starts at the “Kulturcafe”, a meeting point for students, and leads along the facades and over the rooftops of the buildings, which host the faculty of medicine. 

Campus of the Ruhr-University; the concrete plates
are ideal for liches

As with many urban areas, the Campus of the Ruhr-University is a good place to find many different lichens and mosses. The buildings are made of concrete, whose rough ground is ideal for these organisms to adhere. In addition, the different composition of concrete, which is often made of many various kinds of rocks, provides a potent high diversity of species in a small areal. For example, on a piece of a wall, which is made of very calcareous concrete, you can find lichens, which prefers lime. On the other side, you may find more acid preferring lichens on a concrete wall, which is made of gravel.

Another impression of the areal

Another advantage of such places is the missing of dense vegetation. As a result, Mosses and Lichens are easier to detect and also not in competition with higher plants for light, nutrients and water.

2) About Lichens & Mosses

In past articles, I've already written about the basic attributes and the biology of Mosses & Lichens, so a repeat at this place wouldn't make sense. So, if you want to know more about these very interesting organisms in detail, just look at my other Articles about the the last field trip and the basics about lichens.

3) List of Species

4) Pictures


C. citrina

 C. concolor (yellow)

Cladonia chlorophaea

Cladonia subulata

  Cladonia furcata

 Evernia prunastri - here on a wall and not on a tree

 Flavoparmelia caperata

 Hypogymnia tubulosa

Hypogymnia physodes

Lecanora dispersa

 Lecanora muralis

Stereocaulon vesuvianum

Physcia caesia


 Grimmia pulvinata

 Bryum caespiticium

Polytrichium juniperinum

Bryum argentum

 Bryum barnesii

Ceratodon purpureus

 Funaria hygrometrica

Tortula ruralis

Other species

 Dacrymyces stillatus (orange spots on wood)
 Paranectria oropensis (orange spots on the lichen)

Geastrum triplex

Montag, 3. Februar 2014

Species of the Day (February 3rd, 2014) - Geastrum triplex Jungh.

This time, I have a special kind of fungus for you. This species is Geastrum triplex Jungh. from the Geastraceae Family. In German, this species is known as “Halskrausen-Erdstern”. The common English name of this fungus is “Collared Earthstar”, what is also the literally translation of the German name.

1) Description

G. triplex is a larger fungus, whose mushrooms (the fruit bodies, which carry the spores) reach 6 to 10 centimeters in diameter. The above-ground mushrooms grow in stocks of two or three fruit bodies per stock.

G. triplex - habitus

The most distinctive feature of G. triplex (and the most other species from the Genus Geastrum) is the habitus of the mushrooms, which remind of tuber, which grow in a star-shaped rosette. These habitus is a result of the ripening. Young mushrooms are tuber-shaped, when they sprout from the ground. Basically, a mushroom of G. triplex consists of two different layers: the Exoperidium and the Endoperidium with the spores. During the ripening, the Exoperidium breaks up and forms a saucer-like pedestal for the smaller Endoperidium. Later, the Exoperidium tears up into star-shaped rays, which surround the Exoperidium. A stem is missing.

Ripening of a G. triplex mushroom: 1) intial phase; 2) medium phase
3) final phase (with spore erruption)
(exp =  Exoperidium; end = Endoperidium (in 2) with cracks; in 3) star shaped;
s = spores; h = hyphae; o = ostiole; c = collar)

This process is typically for all fungi from the Genus Geastrum. In addition, the Endoperidium of G. triplex also flakes off at the base and form a kind of collar around the Endoperidium. This is also the reason for the name “Collard Earthstar”. However, this collar may be missing or be only very inconspicuous. This leads to confusion with other species of the same Genus. In the most cases, G. triplex is confused with the similar Geastrum sessile (Sow.) Pouz., which is much smaller and never has a kind of collar.

G. triplex - younger mushroom in phase 2

As I said it before, the spores are inside the Endoperidium and leave it after ripening by the large pore at the the top of the mushroom (in Mycology: Ostiole). This eject often happens by an abrupt eruption. The spores are spherical and between 3 and 4 micrometers in diameter. They are also covered with some warts.

G. triplex - two mushrooms in phase three; the
ostiole and the collar are visible

G. triplex isn't poisonous. However, the whole fungus is completely uneatable, because the tissue is tough and has no taste.

2) Distribution

G. triplex is a cosmopolitan and can be found all over the world (e. g. in Europe, North America South Africa etc.). It's a saprobe and thrives on dead, organic matter, from which it gets its nutrients by decomposing. Normally, this species can be found in deciduous forests on lime in the undergrowth or along rotten trunks and tree stumps. However, it can also be found sometimes in parks or bushes with a high entry of organic matter. I found this fungi on the campus of the Ruhr-University in Bochum, Western Germany.