Montag, 25. März 2013

Plant of the Day (March 25th, 2013) - Thujopsis dolabrata (Thunb. ex. L. F.) Sieb. & Zucc.

After I have already shown you two of the five ”Holy trees of Kinose”, it's now time for another tree from this group. This tree is Thujopsis dolabrata (Thunb. ex. L. F.) Sieb. & Zucc. from the Cupressaceae family (Cypresses). In English, this plant is known as “false arborvitae” or
“hiba arborvitae”, while in German, it's called “Hiba-Lebensbaum”. In Japan, the tree is known as
asunaro (あすなろ).

Thujopsis dolabrata - habitus (sort "nana")

T. dolabrata is a medium high, evergreen tree, which can reach a maximum height of nearly 15 metres (feet). However, dwarf sorts are also very common. For example, my picture shows the sort “nana”, which reaches a maximum height of only 60 centimetres. 
The colour of the thin bark varies between reddish brown and grey. The small, scale-like leaves are bright green to yellowish green. As with the most members of the Cupressaceae, there are two morphological kinds of leaves: lateral leaves and central (or facial) leaves, which lie flat on the branch.

T. dolabrata - branches and leaves (dorsal site)

The central leaves are inverted egg-shaped (obovate) and appressed, while the lateral leaves are more keeled and lanceolate. They are also a little bit curved and protruding. However, the most distinctive feature of the lateral leaves are the bright and broad ligaments of stomata, which can be found on their ventral side. Both types of leaves are overlapping each other and are between 4 and 7 millimetres long and 2 millimetres broad.

T. dolabrata - branches and leaves (ventral site) -
you can see the bright stomata

T. dolbarata is monoecious, so we have male and female cones on each plant. The male cones are very inconspicuous. They are green and cylindrical. The female cones are spherical and are built of eight fertile seed scales. Female cones are green at first but they lignify with their ripening and get a greyish colour. The pollen fly between March and April.

 T. dolabrata - branches and leaves (dorsal site) - 
closer look: l = lateral leaves; f = facial leaves; s = stomata

At the first glance, T. dolabrata looks very similar to an arborvitae (Genus: Thuja) and the species also belonged to this Genus for a long time. The high similarity to an arborvitae is also the reason for the Latin name “Thujopsis” (what means something like “Thuja like”) and the English name “false arborvitae”. In German, the species is still known as a “Lebensbaum” (German translation of arborvitae).

Thuja occidentalis - brances and leaves; as you can see
the leaves are much smaller and the stomatas aren't so bright
(d = dorsal site; v = ventral site) 

However, there are some differences between the Genera Thujopsis and Thuja. The leaves of T. dolabrata are broader and the female cones are spherical, while the ripe, female cones of a Thuja are more cup-like. So today, T. dolabrata is the only known species of the Genus Thujopsis (a monophylum).

T. dolabrata - habitus

T. dolabrata is endemic to Japan. It grows in cool and moist conifer forests and groves. Its areal reaches from the lower coast to the mountainous regions. As one of the five “Holy trees of Kinose”, this species is also a very popular ornamental plant for temples and shrines. In Europe, small sorts like “nana” and "variegata” can be found in parks, gardens or on cemeteries.

Dienstag, 19. März 2013

Conifers of the Puplic Cemetery in Bochum-Weitmar (Field-Tripp March 3rd, 2013)

Last Sunday, I participated in a field trip to the municipal cemetery in Bochum-Weitmar („Städtischer Friedhof Bochum Weitmar“) in Bochum, West Germany.

1) The Cemetery

As a municipal cemetery, the plant is operated and maintained by the City of Bochum and not by a religious community (in contrast to the catholic cemetery of Bochum Weitmar, which is right next door and operated by the St. Francis community).

the main entrance of the cemetery

As with the field trip in the last year to the cemetery in Herne, the focus was on the different species and sorts of conifers and evergreen plants. Because they are evergreen, such plant are very popular ornamental plants for cemeteries, because they symbolize eternal life and immortality, what is an refer to the immortality of the soul. However, as I mentioned before, evergreen plants aren't really “evergreen”, within the meaning of that they never lose any leaves. This plants also lose their leaves but not all at once like the seasonal green plants.

 the cemetery - note the open, park-like landscape

As cemetery plants, the conifers and evergreen shrubs must meet certain requirements. One of them is the size, because plants on graves may not exceed a maximum size, witch is determined by the city (the exception are trees, which are planted by the city itself). Another requirement is the shape. On a cemetery, leaves with hanging branches, needles or leaves are preferred, because they symbolize mourning and tears.

2) Haus Weitmar

As a kind of expansion, the field trip also made a short detour to the grounds of Haus Weitmar. Haus Weitmar is a very popular location in Bochum. These are the remains of a medieval mansion, which was build in 1592 by the nobleman Johann von Hasenkamp. Before that, there were only some small houses, which were built in 1464, and an old chapel (the so called “Sylvesterkapelle), which was build in 1397 and is located in the north of the manor.

Schloss Weitmar - the ruins  and the new building

Both Chapel and manor were built with sandstone, which was brought from the near river Ruhr.

Haus Weitmar and its grounds belong to the family von Hasenkamp for nearly 300 year. After the last von Hasenkamp passed away, Haus Weitmar was bought by the family von Berswordt, which are also the owners today.

During the Second World War, the area around the manor was hit by an allied bombing raid at May 13rd, 1943. The bombs destroyed the manor and the chapel almost completely and only some walls remained. To avoid a collapse, a modern art building was built in 1968 within the ruins, which stabilize the cracked walls. Today, this buildings hosts art exhibitions and a small cafe. 

 Schloss Weitmar - the grounds

The grounds around Haus Weitmar were later leased by the City of Bochum, which makes them public for visitors. A special feature of Haus Weitmar are the different species of rare and exotic trees and shrubs, which were planted by the owners. One of these trees were a dwarf beech (a sort of Fagus sylvatica, “Süntelbuche” in German), which was the oldest tree of Bochum until it was destroyed by a fire in 2000. At this time, the tree was over 300 Years old. 

 3) Species

4) Pictures

Chamaecyparis lawsoniana - habitus

Chamaecyparis obtusa - habitus

the ventral site of leaves from C. lawsoniana...

... and C. obtusa

Chameyparis pisifera: Sort "filifere aurea"...

... and "squarossa Boulevard"

 Cupressus arizonica - Arizona cypress

Metasequoia glyptostroboides - bald in the winter

Sequoiadendron giganteum - giant red wood

Platycladus orientalis

Thuja occidentalis: habitus...

... and the ventral site of the leaves

Thujopsis dolabrata - habitus

Cryptomeria japonica
 other conifers

 Tsuga canadensis - Canadian Hemlock

Cedrus atlantica "glauca"

 Araucaria araucaria - Araucariaceae

 Picea omorica - Serbian spruce

 Cedrus deodara

 Pseudotsuga menzisii - Douglasie

Non conifers
 Erica arborea - tree heath

 Ilex cornuta  from Japan

Erica carnea - winter heath

Osmanthus heterophyllus

 Parrotia persica - persian ironwood

 Rhododendron catawbiense

Skimmia reevesiana

 Skimmia japonica

Pieris japonica

Montag, 11. März 2013

Spring impressions


a new Article will be uploaded this week. Until then, I have some spring impressions for you. ;-)

Coryllus avellana (Hazel) - male inflorescences

Crocus agg. - a typical spring plant