Species: Geranium sp.
Common names: cranesbill Swedish name: näva
Geranium is a genus of about 430 species of flowering annual, biennial, and perennial plants. They are found throughout the temperate regions of the world and the mountains of the tropics, but mostly in the eastern part of the Mediterranean region. In Sweden for example there are 14 species of wild growing Geranium. The common name cranesbill derives from the beak-like appearance of the fruit capsule of some of the species. The Geranium genus has a distinctive mechanism for seed dispersal. Where the fruit capsule springs open when ripe and casts the seeds some distance.
There are many cultivated species of Geranium most are hardy perennials treasured for their attractive flowers and foliage. Several hybrids have been awarded, ‘Rozanne’ is one of them.
Description: The long, palmately cleft leaves are broadly circular in form. The flowers have five petals and are coloured white, pink, purple or blue, often with distinctive veining. Some species have spreading rhizomes. Among those there are two cultivars I often use for their ground covering function along with rich blossom. Geranium x cantabrigiense ‘St Ola’ and Geranium macrorrhizum. Both are lovely to use with other perennials as well as with shrubs and trees.
How to grow: Geraniums will grow in any soil as long as it is not waterlogged. The majority need only reasonably fertile and moist soil. A few prefer gritty, well-drained soil. They are normally grown in part shade to full sun. But some works even in shade therefore suitable for woodlands and as ground cover under shrubs. Propagation is by cuttings in summer, by seed, or by division in autumn or spring.
Spieces dependent of forest fires to survive and thrive
The great forest fire in Tyresta National Park, Sweden.
In August 1999 ten per cent of the national park and nature reserve burnt down. For about two weeks fire fighters tried to extinguished the fire before getting it under control. The extremely hot and dry conditions contributed to the extent of the fire and made it very difficult to put out.
The fire in Tyresta National Park was a tragedy in many ways. The park is known as a valuable area of unspoilt natural beauty. It is uncommon with such an old forest so close to a large city, Stockholm. Many plant and animal species dependent on an unharmed habitat were threatened and lost. At the same time, fires are a natural part of the life circle in primeval forests and from an ecological point of view not a disaster. Fire may start a natural regeneration of the forest.
The natural chaos in the aftermath of a fire is beneficial for many species. Geranium lanuginosum and Geranium bohemicum are two floral species that depends on fire for their seeds to germinate. They have to be heated to 50-100 °C. Their seeds may lie latent in the soil surviving for a long time (in some parts of Tyresta for 200 years). In today’s society we are extinguishing the forest fires very fast which leads to only small areas of forests get burnt yearly. Due to this many fire dependent species are endangered or close to extinction. Svedjebruk, controlled slash-and-burn, is necessary to save and keep these spieces alive.