Freitag, 17. Januar 2014

Plant of the Day (January 17th, 2013) - Lagarostrobos franklinii (Hook. f.) Quinn.

Again, we return to the fascinating world of the Podocarpaceae. This time, I will show you Lagarostrobos franklinii (Hook f.) Quinn. In English, the species is known as “Huon pine” or “Macquarie pine”. Because the species isn't well known in Germany (and is also not a ornamental plant), there is no German name for this species. However, the English name “Huon Pine” (or “Huon Kiefer”) is also used.

L. franklinii is the only species of the Genus Lagarostobos (a Monophyllum). Earlier, the species belonged to the Genus Dacrydium.

1) Description

L. franklinii is a large, evergreen tree, which can reach average heights between 10 and 20 meters (32.8 to 65.6 inches). However, some individual trees can also reach a maximum height of nearly 30 meters (98.4 inches). It grows upright in a pyramidal shape with long, slender branches. Despite the stately heights, L. franklinii isn't a fast growing species and grows only 1 mm per year. On the other site, the species is one of the longest-living trees in the world. There is a stock of off-shoots (found at Mt. Read in Tasmania), whose Genom is about 10.000 years old, while the oldest, still vital tree of this stock is about 2.000 years old. The Bark has a distinctive, gray color.

 L. franklinii - habitus

As I mentioned it before, the branches of L. franklinii are long and slender. Along them, the leaves are arranged in a spiral leaf-pattern. They are very small (only about 1 millimeter long), scale-like shaped and closely pressed at the trunk but they are also strong keeled. All in all, the foliage reminds at a Cypress (Cupressus agg.). However, the leaves of L. franklinii also have white stripes of stomata on their back, what is a good difference between these two genera.

 L. franklinii  - the greyish bark

L. franklinii is dioecious, so we have male and female cones on different plants. In both cases, the cones are located at the end of the twigs. These cones are tiny and consists of 4 to 8 scales (male and female cones). After successful pollination, the female cones become small, globular seeds, which are surrounded by a fleshy mantle (Arillus). Vegetative propagation per off-shoots is also possible.

2) Distribution & Ecology

The tree is endemic to the Island of Tasmania, South of Australia. It grows in the riparian forests of the island and can be found along rivers, streams and creeks in the southern and western region of Tasmania. It uses the water for the distribution of the seeds and grows from sea-level to an altitude of 600 meters.

 L. franklinii- foliage; some cones are also visible
(red circles)

Over-exploitation and extensive logging (the wood is high quality because of its golden yellow color) had threatened the species and forced it into a serious bottleneck. However, the species is recovering, but because of the slow growth, adult trees are still rare. As a result, L. franklinii is protected by law.

Montag, 13. Januar 2014

Plant of the Day (January 13th, 2014)- Pherosphaera fritzgeraldii (F.Muell.) F.Muell. ex Hook.f.

This time, I want to take a closer look to another species from the Podocarpaceae, a family, which I'm connected with in a special way. This species is Pherosphaera fritzgeraldii (F.Muell.) F.Muell. ex Hook.f.. In English, this species is known as “Dwarf Mountain Pine” or “Blue Mountains Pine”. In German, the species is known as “Zwerg-Strobe”.

the old name

Please note: in many books, you will also find the name Microstobos fritgeraldii. This is the old name of the species, based on the old taxonomy. In some old literature, you'll also find the name Dacrydium fritzgeraldii. This is from a time, when the Podocarpaceae consisted of only a few different Genera.

1) Description

P. fritzgeraldii is a small, mostly inconspicuous conifer, which reaches only a maximum height of one meter (39.5 inches). It grows as ascending or creeping shrub, which can reach about two meters (78.5 inches) in diameter. As you may see on my pictures, the plant is richly branched. These branches are dropping.

P. fritzgeraldii - habitus

The leaves are only about 3 millimeters long. They are decurrent, so there is no petiole and the most part of the leaf-blade lays directly at the shoot. However, they are strongly keeled and the narrow tip of the leaf blade is curved to the outside. All leaves have a have white line of stomata on the inner sites. This inner site have a olive green color, while the outer site is a little bit darker. In both cases, the leaves are shiny. 

 P. fritzgeraldii - a closer look at the plant; you
cab see the keeled leaves with their curved tip

P. fritzgeraldii is dioecious, so we have male and female cones on different plants. In both cases, the cones are located at the end of the twigs. The male cones are brown, about 6 millimeters long and have a ovate shape. The female cones are smaller (only between 2 and 4 millimeters) but they have a more conspicuous, reddish color. Each female cone consists of 4 to 8 fertile scales.

P. fritzgeraldii - another look at the foliage;

As with the most Podocarpaceae, the roots of P. fritzgeraldii are covered with small root nodules, which acts as host for Endomycorrhiza.

2) Distribution

As the name suggest, P. fritzgeraldii is endemic to the Blue Mountains in New South Wales, Australia, where the species can be found between 650 and 1000 meters about sea level. It prefers moist, shady places on sand and grows only on the south-exposed slopes and cliffs in the zones of spray of waterfalls or mountains creeks within these mountains.

P. fritzgeraldii grows in dense shrubs

Botanists believe, that the species was widespread in many other parts of Australia in prehistoric times, but hot temperatures, drought and wildfires forced it to retreat to a such extreme limited habitat in order to avoid extinction.

Montag, 6. Januar 2014

Plant of the Day (January 7th, 2014) - Sedum kamtschaticum Fisch. & C. A. Mey.

The first plant of 2014 is Sedum kamtschaticum Fisch. & C. A. Mey. from the Crassulaceae family. In German, the species is known as “Kamtschatka-Fetthenne” (“Kamtschatka” is a Russian peninsula in the Far East). The common English names of this plant are “Kamtschatka Stonecrop” or “Orange Stonecrop”.

1) Description

S. kamtschaticum is a small, perennial plant, which can reach heights between 10 and 30 centimeters (4.0 to 12.0 inches). However, there are many offshoots, which spread from short rhizomes. Thereby, the species grows in dense cushions, which are about 23 to 31 centimeters (9.0 to 12.5 inches) in diameter. As with the most species from the Genus Sedum the plant has a thick an fleshy stem, which makes it very resistant towards dryness and drought.

S. kamtschaticum - habitus

This also applies for the flat leaves, with their thick, glossy cuticula, which provides extra-protection against to evaporation. They have a dark-green color on both sides and are cuneate to inverted lanceolate. The margin of the leaves is irregularly serrated or lobbed, while the petiole is missing or very short. The leaves are also curved slightly inwards to create a groove, which collects water.

 S. kamtschaticum - leaves; you can see the glossy 
cuticula of the leaves

S. kamtschaticum is an evergreen plant. However, the color of the stalk change to a reddish pink during autumn. Later, the leaves get the same color before they are dropped (see my pictures, which I made in autumn). The species endures the cold months in form of a green rosette.

S. kamtschaticum - the star-shaped flowers with
their bright petals

The inflorescence is a cyme, which is rich of small flowers. Each Flower is fivefold, so we have five petals, five sepals and so on. This gives the whole flower a star-shaped appearance. The petals have a distinctive, golden-yellow to orange color. Flowering time is in midsummer between May and June.

The ripe fruits are follicles. In botany, a follicle is a single carpel, which contains more than two seeds and opens after ripening to release these seeds. In this case, the follicles of S. kamtaschaticum are made from the five, orange carpels in the center of the flower

2) Distribution

As I said it before, S. kamtaschaticum is native to the Far East but not only on the Kamtschatka peninsula. It also grows from the Ural mountains to Mongolia and Siberia. Here, the plant has to endure extreme dryness, hot temperatures in the summer and very cold winters. As a result, the plant is highly tolerant towards these factors. Its succulent habitus protects it against drought and to grow in dense cushion is typical for plants in regions with such cold winters. By the low growth, the plant is covered with snow during the harsh months, what protects the vegetation buds against freeze.

S. kamtschaticum - another view of the plant.
the red stalk is visible
Because of its high tolerance toward drought, S. kamtschaticum is also a very popular plant for gardens and rooftops. It's often planted on rooftops in order to give them a green and more natural flair.