Here is a plant that is topical with the many fires in the South. The plants of this family are pyrophilic. Pyrophilia is the property of a living organism to derive benefit from fire, here a plant. Cists are characteristic of Mediterranean countries. No wonder our region has about as many as the fingers of one hand.
You may be lucky enough to see her during your vacation.
Scientific name: Cistus albidus L., 1753
Other common names: Ciste blanchâtre, Ciste cotonneux
Origin of the name: its Greek name “kiste” which means basket, box, comes from the shape of its fruits. Its species name "albidus", white, is not related to the color of its flowers but to that of its very cottony leaves.
German common name/dialect: Weißliche Zistrose
English common name: grey-leaved cistus, rock rose, white dart
Date of sighting: July 17 in Gravesson (13)
Plant family: that of the Cistaceae which includes cistus, rock rose, fumana
They are small shrubs, shrubs and perennial or annual herbs, rather present in the Mediterranean areas. The leaves are usually opposite and simple, often leathery.
The flowers are solitary or in a cymose inflorescence. Their symmetry is of order 5: 5 brightly colored petals often wrinkled or crumpled, quickly obsolete, 5 sepals, often very numerous stamens (100). They ripen from the inside out which is unusual, and hide the stigma which ends at the base in an ovary in 3, 5 or 10 parts.
This cistus flower resembles that of the mallows to which it is close. The Cistaceae (Cistaceae) are also grouped with the Malvaceae (Malvaceae) and Tiliaceae (Tiliaceae), the lime trees, in the order Malvales.
Role of Cistaceae in fires and ecological role:
Rockroses settle in abandoned fields and pastures. They are also pioneer plants that grow first after forest fires, maquis and garrigues (or scrubland).
The fire and its heat breaks the dormancy of the seed and causes the seeds to germinate. They are very flammable plants in summer. They thus maintain a high cycle of fires where they are. They are flammable material and at the same time seed banks hidden in the ground which germinate immediately after the fire
Category: typical scrubland shrub with large pink flowers
Height: 50 to 120 cm high
Stems and roots: erect woody stems
Leaves: sessile, entire, flat, oval, and opposite. They are whitish on both sides because they are covered with small stellate hairs.
They measure up to 6 cm long and 0.5 to 3 cm wide and have 3 marked ribs on the underside.
To survive in arid lands, this plant has developed, like other species in these arid ecosystems, a lot of hairiness. Fine hairs form a felt that insulates the tissues of the plant from the dry outside air and slows down its dehydration.
Flowering: April to July
Flower colour: 40-60 mm pink flowers with radial symmetry. Its five petals are crumpled. These flowers are solitary and arranged in cymes, on branches a few cm long which branch out in pairs and stop their growth with a flower at the end.
The stamens are very numerous and have bright yellow anthers which hide the style of the same length
The calyx with 5 pointed sepals (3 to 5 mm) is green.
Pollination: by insects. Plant rich in pollen and very attractive to them.
Possible confusion: yes with hybrids of this species and other cistus of the same color such as the frizzy, tense cistus, Cystus crispus, but whose leaves are wavy, tense. On the contrary, those of Cystus albidus, star of the day, are flat.
Fruits: the fruits are woody capsules, oval 4 to 6 mm, which release, through 5 valves, small seeds of 1 to 2 mm which are disseminated by animals.
Habitat: typical species of clear forests, burnt areas of scrubland and maquis of southern France, from Portugal to Italy and to the near Maghreb.
Protection: fairly common plant, not protected by law but classified Znieff in the Midi-Pyrénées region.
Ecology: this plant has been the subject of much research in Spain;
Seed viability(1): not affected by age (tests on 3, 8 and 13 year old seeds). However, older individuals have fewer flowers. Physiology in the event of water stress (2): plants in very dry environments have better photochemical functioning during very dry periods than those in more watered environments. This may be the result of natural plant selection.
Another study (3) did not show a significant difference in the amounts of enzymes despite significant DNA variations. The substrate on which the White Cistus grows determines when water stress appears in times of drought. It starts at 13 days on a commercial substrate (sphagnum, coconut fiber, perlite) and at 53 days with a more complete compost (slurry, coconut fiber, perlite).
A recent study (2021) showed the link between the accumulation of vitamin E in the plant and jasmonic acid, an already known plant hormone. A close component (OPDA) of this acid has the opposite effect. This proves a regulation of vitamin E by jasmonates. Vitamin E is a plant stress response. This type of discovery makes it possible to better understand how plants resist water stress. Understanding all these mechanisms will make it possible in the future to seek out and select the plants that are the most resistant to episodes of heat wave and drought.
Horticulture: rockroses, including this one, are often planted in gardens because of their very beautiful flowers and their ability to grow in dry soil.
Cists are frequently parasitized by Cytinet, Cyttinus hypocistis, a very curious plant to which we will return on occasion.
Food use: the leaves of this plant are used for the preparation of digestive infusions and to prevent gastric pain.
It would have been used for its bactericidal, analgesic and anti-inflammatory properties. The leaves as a poultice were used to cure abscesses.
There is cistus officinalis, rich in pharmacological powers and in particular, a good healing potential. This is the Cistus ladaniferus, Cistus ladaniferus. Its properties have been known for a long time since it is already mentioned in the Bible alongside myrrh and frankincense.
No citation of this cistus in wikiphyto
Active components found in this plant are large amounts of tannins, leucoanthocyanins and glucosides. They explain its vulnerary properties. Clinical tests remain to be done to better use this plant.
As always, and before any use, you should consult a doctor to be warned of possible adverse effects as well as possible interactions with conventional medications.
Text, photos, bibliography Roland Gissinger (Anab) ) Proofreading Bernard Weinzaepflen (Anab)