Monday, April 27, 2015

Judas tree

Judas trees, called erguvan in Turkish, are a symbol of Istanbul. When they flower in late March and throughout April the slopes on either side of the Bhosphorus are a sight to behold. The flowers come before the leaves, displaying their strikingly deep pink color profusely.

       

I was born in Istanbul but I didn’t come to live there until 1969, the year I started university. In those days urban development had not yet engulfed the natural environment. The slopes of the Bosphorus Strait were green and mostly untouched. I fell in love with what I saw and to this day I try to match every other place I visit or live in to that beauty entrenched in my memory.

Each year the blossoming of the Judas trees is noted by Istanbulites.



Judas tree or Cercis siliquastrum of the family Fabaceae is a small deciduous tree from Southern Europe and Western Asia. It grows up to 12 meters in height and 10 meters in width.

In 1753 Linnaeus used the name 'siliquastrum' derived from the Latin word 'siliqua' meaning pod to describe this tree. The genus name 'cercis' comes from the Greek word 'kerkis' meaning shuttle. The long, woody seedpods that hang vertically were likened to the tool used by weavers.

weaver’s shuttle

The origin of the common name is not certain. One explanation is that the name Judas is a corruption of the word Judean meaning the land of the ancient Judah tribe where the trees used to grow.

The flowers are produced on year-old or older growth, including the trunk which is called cauliflory. They are hermaphrodite and bees pollinate them. They are edible.



                                                            
The heart shaped leaves appear shortly after the first flowers.
                                        

Monday, April 20, 2015

Posidonia oceanica



Posidoniaceae is one of the 5 families of seagrasses, descendants of terrestrial plants that re-colonised the ocean between 100 and 65 million years ago. Seagrasses are monocotyledons (also known as monocots, one of two major groups of flowering plants or angiosperms that are traditionally recognized, the other being dicotyledons, or dicots) that are not true grasses (family Poaceae) but are closely related to the lily family, Magnolyophyta (http://www.marbef.org/wiki/mediterranean_seagrass_ecosystem). This kind of rich knowledge about plants accumulated over hundreds of years always amazes me.

The sole genus of the family Posidonia has 9 species: Posidonia angustifolia, P. australis, P. sinuosa, P. coriacea, P. denhartogii, P. kirkmanii, P. ostenfeldii, P. robertsonae and P. oceanica.

P. oceanica, common name Neptune grass, is named after the god of the sea. Poseidon is one of the twelve Olympian deities in Greek mythology. In Roman mythology he is Neptune.

My friends and I used to challenge ourselves to reach the darker waters above the P. oceanica meadows that were 150 or maybe more meters out from the shore at the Kadınlar Denizi beach in Kuşadası where we went swimming in the summers during the ‘60s and ‘70s. Several times a season decaying leaves from these meadows would hit the shore en masse. This phenomenon would usually take place at night and we would wake up to a beach line covered with dead dark brown leaves. This didn’t perturb us for we could easily walk over them and jump into clean clear waters with beautiful sand at the bottom all the way to the P. oceanica meadows. The grass would be gone the next day, carried away by the waves. Having Neptune grass in the sea is an indication of non-pollution in fact. This grass grows best in clean waters.


                              A picture of the town of Kuşadası (c. 1935) showing decaying Neptune grass that has hit the shore

There was another small bay nearby where the shore was permanently covered with dead leaves several meters high. I remember going out for a family picnic on this bed of grayish-brown dry leaves one time. The pile was soft and bouncy under our feet. It all depended on the currents, the winds and the compass direction the beaches were facing.


                                                          P. oceanica beds on the west coast of Corsica, in 2000

There is extensive research on P. oceanica and its significant role in littoral (coastal regions) Mediterranean ecosystems. Here are some facts about Neptune grass: It forms large underwater meadows in the submerged photic zone of sheltered coastal waters, photic meaning enough sunlight penetrates to permit photosynthesis; it has high rate of production which is the synthesis of organic compounds from carbon dioxide making it a high producer forming the base of the food chain; it structures and stabilizes the seabed thus creating habitat for many marine organisms.

P.oceanica is one of the largest, slowest growing, and longest-lived plants. In a genetic study of P. oceanica populations across the Mediterranean, individual clones spanning up to 15 km have been found. Based on the plant's known growth rate, such individuals are likely to be thousands, possibly tens of thousands of years old (Arnaud-Haond et al. 2012-http://eol.org/pages/1089001/overview).

This species is found only in the Mediterranean Sea occupying an area of only about 3% of the basin. This corresponds to a surface area of about 38,000 square kilometers. With their origin possibly dating back to the Pleistocene, some P.oceanica meadows have shown great resilience, persisting through environmental changes over millennia (http://eol.org/pages/1089001/hierarchy_entries/56317045/overview). Today, however, research indicates that P. oceanica populations are declining rapidly. This is due to human-induced disturbances such as coastal construction, trawling, fish farming, and climate change. Researchers warn that the ancient meadows of P. oceanica are declining at a rate several hundred-fold faster than the rate over which they spread causing an unfavorable situation this slow-growing, long-lived species of seagrass is poorly capable of recovering from.

                                                                                               dry rhizomes

As a lay admirer of this great plant I have been noticing for some time that the situation isn’t what it used to be in my youth. We used to find rhizomes of P.oceanica on the beach sand sometimes. There would be egagropili, the fibrous balls formed from materials of dry foliage and rhizomes shaped into balls by the under current, sitting on the sand. Most of them were 3-5 cm in diameter and perfectly spherical. They would feel like felt to touch. The one in the picture that I have kept is oval.

                            egagropili 

I do not remember seeing the fruit of P. oceanica. I am learning that the fruit is free floating and known in Italy as "the olive of the sea" (l'oliva di mare). They resemble small green olive drupes.


                   The Dilek Peninsula National Park and Kadinlar Denizi beaches on the Aegean Sea in Kuşadası


Kadinlar Denizi was one of the best beaches in the whole Mediterranean, I am sure. I don’t think that is quiet true anymore.

Things Mediterranean:

         

Monday, April 13, 2015

Rock rose

                                   Rock rose growing out of a crack in the asphalt. This picture was taken in California in April, 2008.

I remember noticing the white rock rose for its beauty. I would see two or three flowers on a plant that appeared to be weed like. It would be along cracked sidewalks or in rocky and dry grassy places. I never imagined rock roses could form pretty garden shrubs as seen in the following picture taken in California, near the San Francisco area.



When it came to learning the binomial name of the rock rose that I only recognize by sight, I had to look into the family Cistaceae and various genera in the family.

The Cistaceae (rock-rose or rock rose family) are a small family of plants. This family consists of about 170-200 species in eight genera, distributed primarily in the temperate areas of Europe and the Mediterranean basin, but also found in North America; a limited number of species are found in South America. Most Cistaceae are subshrubs and low shrubs, and some are herbaceous. They prefer dry and sunny habitats. (http://en.wikipedia.org/wiki/Cistaceae)

Keeping in mind the rock rose I know, we continue with a selective description: The plants often have showy yellow, pink or white flowers, which are generally short-lived. The flowers are bisexual and they usually have five petals. The petals are free, usually crumpled in the bud. They have five sepals, the inner three of which are distinctly wider, and the outer two are narrow. Sepals form the calyx of a flower which is a sort of whorl enclosing the developing bud, and opens up with the blooming flower. The sepal arrangement is a characteristic property of the family.

The stamens (the pollen producing reproductive organs) are numerous, of variable length, and sit on a disc; filaments are free. The ovary is superior (above point of insertion of the petals, sepals and stamens). The fruit is a capsule, usually with five or ten valves. The seeds are small, with a hard, water-impermeable coating, weighing around 1 mg.
                                                         The fruit of rock rose is a pentagonal capsule, 5–7 mm long.

Two important ecological properties, mycorrhizal ability and fast renewal after wildfires, gives Cictaceae the chance to thrive in Mediterranean habitats.

A mycorrhiza is a symbiotic association between a fungus and the roots of a higher plant that has specialized tissues for conducting water, minerals, and photosynthetic products through the plant. Most Cistaceae have the ability to create symbiotic relationship with root fungi of the genus Tuber. In this relationship, the fungus complements the root system in its task of absorbing water and minerals from the soil, and thus allows the host plant to dwell on particularly poor soils.

Cistaceae have also adapted to the wildfires that are common place in their native habitats. The plant seeds have a hard coating that is impermeable to water, and thus the seeds remain dormant for a long period of time. This together with their small size allows it to establish a large seed bank rather deep in the soil.

Within Cistaceae, eight genera are recognized, including five in the Mediterranean (Cistus, Fumana, Halimium, Helianthemum, Tuberaria) and three in the temperate regions of North America (Crocanthemum, Hudsonia, Lechea). It was difficult to know if the genus I needed to look into was Halimium, Helianthemum or Cistus. Halimium is a genus of 12 species in the family Cistaceae native to Europe, NorthAfrica and Asia Minor, with the center of diversity in the western Mediterranean region. Helianthemum is a genus of about 110 species distributed throughout the Northern Hemisphere, especially in the Mediterranean.

I concentrated on Cistus, a genus containing about 20 species They are perennial shrubs found on dry or rocky soils throughout the Mediterranean region, from Morocco and Portugal through to the Middle East, and also on the Canary Islands. They have showy 5-petaled flowers ranging from white to purple and dark pink.

Cistus salviifolius, common name Sage-leaved Rock Rose in the genus Cistus is the rock rose I know and it is favored by gardeners. The name Cistus from the Greek word kisthos (κίσϑος) means basket, while the species name salviifolius refers to the wrinkled leaves similar to those of the sage.


Cistus salviifolius is a typical maquis plant of the Mediterranean. It is a rock rose that has been introduced into California. The stems are covered by clumpy hairs. This bushy shrub reaches on average 30–60 cm in height. The five white petals have a yellow spot at the base, forming a corolla 4–6 cm in diameter. The stamens are also yellow and the anthers, the part of the stamen that produces the pollen, shed abundant yellow pollen. This plant is pollinated by insects and especially bees. The flowering period extends from April through May. The leaves are evergreen. No water or fertilizer is necessary from April until mid-October.

They are a joy to come by in the most unexpected places.

Monday, April 6, 2015

Chenomeles Japonica

I was six when I started walking to school. One particular thing I remember from those walks is a small shrub in a park that my mother called French bahar. Bahar is the word for spring blossoms of fruit trees in Turkish.


At a much older age I saw another one of these shrubs and I was told that it was called Japanese bahar. This was closer to the truth. I found out that this plant is Chenomeles Japonica. I am surprised to learn that it also bears fruit.

                                                                            Photograph: Tülay Karayazgan

I learn that the fruit is very hard and astringent and very unpleasant to eat raw. They can be used for making liqueurs and marmalade and preserves.

Chenomeles Japonica is commonly called Japanese quince. Chaenomeles is a genus of three species of deciduous spiny shrubs, usually 1–3 m tall, in the family Rosaceae. They are native to eastern Asia in Japan, China and Korea. These plants are related to the quince (Cydonia oblonga) and the Chinese quince (Pseudocydonia sinensis).

C. japonica blooms from February to April before the leaves appear and the blossoms are a rich golden red. The leaves are bronze-red when they start forming, turning green as they grow to their full size. The fruit is yellow and they resemble small quinces.


                                                                                                    Istanbul 2009

I will look forward to seeing the fruit of the shrub in the picture one day.