Montag, 30. Januar 2012

Plant of the Day (January 30th, 2012) - Tremellia mesenterica Retz. Fr.

During the fieldtrip at the Ruhr-University in Bochum, a participant of the event found a very interesting fungus. I didn't mentioned this species in my last article, because the focus was on Lichens & Bryophytes; a fungus would not fit in this topic. So, today, I want to tell you something about this fungus. It's Tremella mesenterica Retz. Fr. from the Tremellaceae. In German, this plant is known as “Goldgelber Zitterling”, while in English, common names of this species are “golden jelly fungus”, “yellow brain”, “yellow trembler” and “Witch's butter”.

T. mesenterica - habitus

The golden-yellow to honey-yellow mushroom has 3 to 10 centimetres (1.25 to 4 inches) in diameter. It's gelatinous and has many convolutions and ridges. Thereby, the mushroom looks like a small, yellow brain, which is also the reason for names like “Yellow Brain”.

The dry mushroom is only a thin organe layer on the wood. It gets his brain-like habitus only by becoming wet.

The spores are egg-shaped and has a messurement of 7-11 x 7-9 micrometres. The sporepowder is white or pale yellow.

T. mesenterica -  on a branch

T. mesenterica is a parasite, which infects other fungi. These hosts are wood-decomposing fungi, which grows on the wood of angiosperm trees like alder, acer or beeches. The species is a cosmopolitan and can be found all over the world.

Unlike the allegation in some literature, this fungus is not poisonous and edible. However, the tough, rubber-like mushroom has no special flavor and tastes very insipid.

Freitag, 27. Januar 2012

Crypotgams of the Ruhr-University of Bochum

1. Introduction

During the last day, I participated in a little Field Trip to the Ruhr-University in Bochum (Western Germany). The topics of this field trip were Bryophytes and Lichens; some of the lesser organisms of nature. However, both are very interesting lifeforms and in this article, I want to give you a small introduction towards Lichens and Bryophytes. It's a very complicated topic, so my goal is to explain you some basic information about these two types of organisms and show you some species, which we've founded during the Field trip.

2. Lichens

Lichens are a very unique type of life. In fact, they're composite organisms, a symbiosis between a Fungus and a photosynthetic partner like an alga or a cyanobacterium. The purpose of this connection is to improve the living conditions of both organisms. However, the fungi benefit a lot more of this symbiosis. Through the photosynthesis of the alga (or cyanobacterium), the fungus has a completely new source of nutrients. But the alga has also an advantage, because the mycelium of the fungus is a good, moist habitat, which protects also from sun radiation. Thereby, Lichens are very undemanding and are able to settle on many different places like rocks, walls but also on wood, stems and so on. To colonize such places is the main advantage of lichens towards over organisms.

Lichens are classified by their habitus and the way they grow. The main types of lichens are
  • crustos: The lichens has a very flat form like a crust with a scurfy, rough surface. Crustos lichens are typical lichens of walls and Rocks.
  • Leafy: Leafy lichens grows area and have a leaf-like thallus (name). The purpose of this habitus is to created a big photosynthetic area like the leaves of the higher plants. Leafy lichens are rich in forms.
  • Branched: Branched Lichens have a shrubby habitus with long “branches”. They often hang from trees and other places.
  • gelatinous: The Thalli (bodies) of these lichens are spongy and swollen. This is a side effect of the symbiosis with cyanobacteria; so gelatinous lichens have often a black or dark blue color.
In general, a lichen is composed of several layers.

The first Layer (A) is the outer bark. It's a dense web of hyphae, which protects the lichen from outer influence. Below the first layer is a loose web of hyphae (B). Here, the algae have settled within the cavities between the hyphae. The third layer (C) is also very loose layer of hyphae but without any symbiont. Finally, the last layer is again a dense web of hyphae and forms the inner bark (D), which lies on the substrat. The Rhizines (E) are root-like hyphae (no real roots). Their function is to anchor the plant on the substrate.

3. Bryophytes

Bryophytes belong to the lesser plants; developed from green algae over 450 Million years ago as one of the first tries of vegetable life to settle on land. However, the main difference between Bryophytes and the Higher Plants (Tracheophyta) is the lack of any vessels. The Bryophytes also have no real leaves, stems or roots, but similar organs called Phylloidae (leaflets), Cauloidae (stem-like structures) and Rhizoidae (root-like structures).

Because of this, Bryophytes cannot control their water cycle and habe no protection against evaporation. However, Bryophytes have the ability to dry out and renature again by wetness. In Biology, this ability is called Poikilhydry

All Bryophytes producing spores as main way of reproduction. The life of a Bryophte is divided into two stages.(s. Picture). The haploid stage is the Gametophyte and the diploid stage the Sporphyte.

In short, the diploid Sporophyte creates spores through meiosis. These spores are located within a spore capsule. After spreading, the spores germinate and form the haploid Gametophyte, which is also the “green part” of the Bryophytes. On this Gametophyte, the Gametangia (the sex organs) are located. There are male and female Gametangia and Bryophytes can also be monoecious or dioecious. The male sex organ creates sperms, which fertilize the female sex organs. Through their fusion, the diploid stage will be started and the sporphyte grows directly on the Gametophyte. In the most cases, the sporophyte is only a brown, inconspicuous structure in comparison to the Gametophyte. This domination of the haploid stage over the diploid is also another different between Bryophytes and higher plants.

In classic taxonomy, the Bryophytes are subdivided into three divisions
  • Liverworts (Marchantiophyta): The habitus (Thallus) of the Gametophyte is lobed to ribbon-like and very small (often only a few millimeters). The Sporophyte is short-lived and inconspicuous. The Thallus is also very oily.
  • Mosses (Bryophyta): the “classic” Bryophytes. The Gametophyte looks like a small plant with leaflets, a stem-like and a root-like structure. The Sporophyte is brown with a long stalk (Seta) and a spore capsule. This capsule is often locked by a hat (Calyptra). The Bryophyta has know oil glands.
  • Hornworts (Anthocerotophyta): Thallus of the Gametopyhte similar to the liverworts with a lobed habitus. Also very small. However, the main difference is the creation and location of the sex organs and the Sporophyte. They are formed endogenously and don't sit on the Gametophyte. Because of this, the mature Sporphytes looks like the horns or funnels of the Gametophyte.
4. Area

The field trip was held at the Campus of the Ruhr-University in Bochum (Western Germany). It was founded in 1962. With 30.000 students, the Ruhr-University belongs to the Top 10 of Germany's biggest Universities today. The total area of the Campus is 4,5 km² (450 ha). Many buildings on the campus are made of concrete. Concrete consists of many different kinds of stone, so it's a good surface for lichens and Mosses. Another important factor are the exhaust of the cars, which help the spores to spread.

Campus of the RUB

So, the Campus of Ruhr-University is a good place to find many different species. On this field trip, the focus is on three locations of the Campus: the walls, a rooftop and last but not least some park trees.

rooftop are good places for lichens

5. Species

5. Pictures

Caloplaca citrina (lichen)

Amblystegium serpens (Moss)

 Asplicia calcaria (white) & Caloplaca citrina (yellow) (lichens)

Atrichum undulatum (Moss)

 Brachythecium undulatum (Moss)

Flavoparmelia caperata  (lichen)

 Cladonia cariosa (lichen)

Cladonia digitata  (lichen)

 Cladonia furcata (lichen)

 Evernia prunastris (grey-green) & Xanthoria parietina (Yellow) (both lichens)

Orthothrichum affine (Moss)

 Hypnum cupressiforme (Moss)

 Hypogymnia physodes (lichen)

 Lecanora muralis (Lichen)

Lunularia cruciata (Liverwort)

Rhytidiadelphus squarrosus (Moos)

Peltigera rufescens (lichen)

 Lecanora caesia (white) & Xanthoria parietina (yellow)

Physcia tenella (lichen)

Polytrichum formosum (Moss)

Xanthoria parietina (lichen)

Sacrogyne regularis (lichen) - white spot on the left

Grimmia pulvinata (left) & Tortula ruralis (right)

Verrucaria muralis (lichen)

Funaria hygrometrica
Pleas note: This time, I've mentioned no determiner, because some names would be to long. If you want the full name check literature or site like wikispecies.

Freitag, 20. Januar 2012

Plan of the Day (January 20th, 2012) - Hypericum perforatum L. agg.

Today's “Plant of the Day” is Hypericum perforatum L. from the Hypericaceae family. In English, you maybe know this plant as  “St. John's wort” or “Tipton's weed”. In German, this species is known as  “Tüpfel-Johanniskraut” (Spotted St. John's wort”) or “Durchlöchertes Johanniskraut” (perforated St. John's wort) and sometimes “Herrgottsblut” (Good Lord's blood).

H. perforatum - habitus

It's a perennial plant, which can reach heights between 50 and 80 centimetres (19.75 to 31.5 feets). It grows upright and has a two-edged , bald stalk. The alternating leaves are oval or egg-shaped and between 1 and 2 centimetres long (0.25 to 0.75 inches). They have no petiole but are covered with many, thin oil-glands. You can see these glands by holding a leaf against the light. It seems to be perforated (name!) by many small, white holes (the glands).

H. perforatum - leaves and stalk

The inflorescences are wide panicles with many flowers. The sepals are green, lanceolate and with a protruding tip. The asymmetrical petals are golden-yellow; with black dots at the edge. Flowering time is between July and August.

 H. perforatum- here, you can see oil glands as white dots

This species is native to Middle Europe and West Asia but can also be found as neophyte in America and Australia. H. perforatum is a pioneer, a plant, which grows at first on a rough ground. So, you can find it e.g. on scree slopes, ruderal wastelands or railway tracks but also meadows, the edges of forests and heaths. H. perforatum prefers dry and lean sites, with a low content of nitrogen within the soil.

H. perforatum - inflorescence

H. perforatum is also a medicinal plant and contains many ingredients like Flavonoids or essential oils. One of these ingredients is Hypericin, a red coloured liquid, which can be extracted by crushing the flowers with your fingers. This Hypericin is used as antidepressant, burns and muscle aches. During the Middle Age, the ingredients of H. perforatum were also used for abortion.

Montag, 16. Januar 2012

Plant of the Day (January 16th, 2012) - Plantago major L. agg.

Plantago major L. from the Plantaginaceae is today's “Plant of the Day”. It's a very common species with many English and German names like “Common Plantain” in English or “Breitwegerich” in German. Other typical German names are e. g. “Wegtritt”, “Großer Wegerich” or “Wegeblatt”.

P. major - habitus

It's a small perennial plant, which can reach heights between 5 and 60 centimetres (2 to 23.5 inches). The crude, egg-shaped leaves are located in a rosette. They have a long petiole (3 to 12 centimetres or 1.2 to 4.7 inches) and between 5 and 9 leaf veins on the back. Their margin is even or a little bit wavy.

The inflorescences are terminal spikes, which are located at the end of a long, leafless stalk. Each spike has a length between 8 and 20 centimetres (3.1 to 7.9 inches). The small, green flowers are very inconspicuous. Flowering time is between June and October. The ripe fruits are small, green capsules with 6-10 seed inside. They are very sticky, so the seeds can be distributed by sticking on wheels, shoes or paws.

P. major - habitus

P. major is native to Europe, but can also be found as Neophyte in many other parts of the World like North America. It is very resistant to pressure and other mechanic influences and also salt, so it grows on paths, trails and even streets and public places, because it's no problem for P. major, if people walk over it . In North America, this species is also called “White man foot prints” by the Indians, because it was brought to their land by European settlers and started to grow at the paths of the White man treks.

Freitag, 13. Januar 2012

Plant of the Day (January 13rd, 2012) - Platanus x hispanica Miller ex. Münchh.

Today, I've a new tree for you. It's Platanus x hispanica Miller ex Münchh (or Plantanus acerifolia (Ailton) Wille.)  from the Platanaceae family. Common English names of this species are “London plane” or “London planetree”, while common German names are “Gewöhnliche Platane” “Ahornblättrige Platane” or “Bastard Platane”

Platanus x hispanica  - is a typical tree in parks

This tree can reach a height until 35 metres (114.8 feet), so it's a big one with a wide crown. The bark of young trees is dark-grey. With age, this bark will fall off into plates. The new, younger bark underneath is yellowish-grey. The leaves are lobed with 3 – 5 deep lobes and sharp ends. The margin is even. So, you can see, that these leaves looks very similar to the leaves of Acer platanoides L. Actually, this is also the reason for the Latin names of both species: “acerifolia” means “similar to acer”, while “platanoides” means something like “looks like a plane”

P. x hispanica - stem with typical, peeling bark

Flowering time is in May. The inflorescence are inconspicuous, small catkins. The flowers are dioecious with male and female ones. Male flowers are greenish, female are carmine. The fruit is compound fruit, which is composed of small, cylindrical nuts. These compound fruits are hanging in groups from long stalks and have spiky, rough surface.

P. x hispanica - leaf (note the similarity to a maple leaf)

P. x hispanica is a hybrid of Platanus orientalis L. (oriental plane) and Platanus occidentalis L. (American plane). In Europe, it's a very popular tree in cities, because it has a high tolerance toward air pollution, smog and dense soils. So, trees are planted in parks, at roadsides or public places and so on.

P. x hispanica - compound fruits

Montag, 9. Januar 2012

Plant of the Day (Janurary 9th, 2012) - Lysimachia punctuata L.

In order to give my visitors from the Northern Hemisphere a little portion of spring feeling, today's “Plant of the Day” is Lysimachia punctuata L., a flower from the Primulaceae. In Germany, this plant is known as “Punktierter Gilbweiderich”. To my shame, I have found no exact English name, but the Genus Lysimachia is known as “loosestrife”, while the literally translation of the German name is “punctured loosestrife”.

L. punctuata - habitus
 (note the hairs)

It's a herb with a height until 100 centimetres (39.25 inches) . The hairy stalk grows straight and is unbranched. The leaves are egg-shaped and until 8 centimetres (3 inches) long. They are sitting directly at the stalk in whorls with 3 – 4 leaves per whorl. Their ventral site is punctured with black dots, what also has given the species it's name.

The inflorescence is a special form of the panicle  The pedunculated flowers are located within the axillary (Blattachsel) of the whorls (with 3 to 4 flowers per whorl). Each flower is radial with five yellow petals per flower. The petals have a egg-shaped and ciliated tip.

L. punctuata - habitus

Sometimes, L. punctuata is confused with Lysimachia vulgaris L., but the inflorescence of this species is a normal panicle and the petals have a red-rimmed tip. The leaves are also narrower and longer.

L. punctuata is an oil plant and contains fatty oils as extra gift for pollinators.

L. punctuata - habitus

Originally, this species is native to Turkey and Souther Europe. As popular garden and ornamental plant, it was imported to the countries of Middle and Northern Europe, because of its ability to endure longer periods of frost. These garden plants started to grow wild and today, L. punctuata can also be found outside of Gardens e. g. on roadsides, ruderal wastelands or scrubs It prefers fresh, bright places with a high content of lime within the soil.

Freitag, 6. Januar 2012

A short introducion to Ecology (January 6th, 2011)

Hi everybody,

it's time for a new “big” article. This time, I want to give you a general overlook about the basic terms of ecology.

1) Vegetation and Plant Communities

Plants are not growing alone, but in interaction with other plants, animals and their environment. The sum of all plants within a definite area is called a plant community and the sum of all plant communities is called vegetation.

2) Ecological factors

Plant communities are not existing randomly. In fact, the composition of vegetation within an definite area is determined by many different ecological factors, which have all an influence on a plant. The most important factors are the follow:

  • Climate: this factor includes everything to do with the weather. This includes precipitation, temperature, solar radiation and so on.

  • Soil: This factor is very important, because the most plants (except the epiphytes) are rooted in the soil. From the soil, they get nutrients and water. So, the factor “Soil” includes things like source rock, humus, pH, salinity or lime
  • Mechanic: This factor includes all things, which can have a mechanical influence on a plant like Wind, Snow, thunderstorms or sandstorms. It's very important factor, because it determines the shape and growing of a plant.
  • Relief: That means, if a plant grows on the south or north side of a slope or e. g. in a valley
  • biotically factors: The influence of other living things on a plant. This includes symbioses, parasitism, competition with other species or individuals and last but not least animal feeding, which can also be a mechanical factor

3) The Definition of an ecosystem

The first four factors are called the abiotical (lifeless) environment. Their entirety within an areal is called Ecotope. The last factor, the interactions between plants with animals or other plants, is the biotical or living environment and their entirety is called biocoenosis. Together, abiotical and biotical environment are forming an ecosystem.

So, the combination of this factors is forming a ecosystem. For example a rocky, south exposed slope on lime is a very hot and alkaline place, so you will find species, which can grow under these conditions. And in a bog, you will find species, which have no problems with wetness, high precipitation and low content of nutrients.

4) Types of Vegation

In the most cases, the climate is the most important factor. Depending on the prevailing climate, a typical vegetation will be formed. This vegetation is called zonal vegetation. For example, the beech forest is the typical form of vegetation in Germany; created by the warm and temperate climate. But in Canada, the coniferous forests are the zonal vegetation and so on.

Beech forrest are the typical vegetation in Germany

However, through the influence by other factors like relief or micro-climate, it's possible, that a vegetation will be created, which distinguishes from these zonal vegetation. For example, a meadow on a hot, south exposed slope in Germany is not the typical, zonal vegetation, but an exception with its own micro-climate. Such a vegetation is called extrazonal vegetation. Extrazonal vegetation includes often rare and unique ecosystems.

A special form of extrazonal vegetation is azonal vegetation. Unlike the other two types of vegetation, the climate is not most dominant factor for vegetation, but soil or mechanics. A good example for an azonal vegetation is a bog but also ruderal wasteland or heavy metal slopes.

heath is a good example for azonal vegatation,
because it's created by soil and mechanical factors
and not by the climate

5) Summary

I hope, that I was able to give you a first overlook about Ecology and phytosociology. In future Articles, I want to introduce you some plant communities and types of vegetation but for now, the most important thing is, that you've learned the basic definition

Sonntag, 1. Januar 2012

Plant of the Day (January 1st, 2012) - Arctium lappa L.

Happy New Year to everybody.

This is the 100th Post of my Blog and I want to say thank you  to everybody, who have visited my blog since it has gone online in April 2011. I hope, I could help you with your search about plant facts. From my experience, I know that it could be very tricky to find informations about plants in the Web. For the future, I want to write some new “big” Articles", which aren't about plants but about field trips or scientific topics.

However, on this New Years Day, I want to show you a new plant. It's Arctium lappa L. from the Asteraceae family. In the German language, we know this plant as “Große Klette” while in English, this species is known as “greater burdock” or sometimes simple as “lappa”

A. lappa - habitus

It's a big plant, which can reach heights between 80 and 150 centimetres (31.5 to 59 inches). The stalk is branched with many upright branches. The basal leaves are egg-shaped or broadly triangular. Their dorsal site is dark green, while the ventral site is grey and covered with many  bristles. The petiole is pithy.

 A. lappa - inflorescences

The inflorescence are round heads. Each head has 1,5 to 3 centimetres ( 0.5 to 1.5 inches) in diameter. Each inflorescence consists of  small radial flowers with purple petals in the centre, which are surrounded by a hull (involucrum) of green bracts. Each of  these bracts have a hook-shaped tip, which is used as a barbed. After successful pollination and ripening, the whole inflorescence will hang in the fur of animals, which will spread the seed by this way..

A. lappa - basal leaves

A. lappa is native to Middle Europe (except Spain and Scandinavia) but can also be found as neophyte in North America. It grows on bright places and likes a fresh nutrient-rich soil of clay. So, you can find it e. g. at roadsides, on scree slopes or railway tracks and other types of ruderal wastelands but also on the shores of rivers, lakes or ponds.

A. lappa - inflorescences with ripe fruits

It's also a medicinal plant. The roots contain essential oils and traces of sulphur. Their extract is used to cure some skin diseases and dandruffs. In Japan, the roots of A. lappa are also eaten. The fruits also contains oil (similar to the oil of the sunflower). This “burdock oil” is used for the production of cosmetics.

The next Article will be posted at Friday. I hope, it will be a new “big one”, but I cannot make a promise yet.