A reason for using native species is that they are better adjusted to each other. Most animals benefit more from native species for food. The bird berry, for instance, is food to 32 native bird species. The similarly decorative firethorn from the Mediterranean offers food to only 4 native bird species. If we would succeed in planting more native bushes, that would offer living space to many more birds, butterflies, bumblebees and other insects. Land Oberösterreich, 2008
The Province of Oberösterreich in Austria has a policy of developing urban green areas in a more natural way. To this end, the following five rules for natural management of urban green areas were established:
- Nutrient-poor = rich in species diversity. Nutrient-poor soils have a colourful variety of species and cost less energy, money and work to maintain.
- Wild plants have priority. Domestic wild plants bring more animals to the city.
- Today’s green waste is tomorrow’s food. Wood chips and compost replace fertilisers and peat, improve the health of plants and reduce maintenance.
- Less care results in greater diversity of species. Many animals’ vital needs, like those of hedgehogs, can be met by leaving leaves, dead wood and some scattered stones and by performing less maintenance.
- Water management should be adjusted to nature. Rain water should be allowed to infiltrate directly as much as possible; if this is not possible, it can be stored in bioswales or ditches and ponds. This way, water-loving plants and animals are catered too. Land Oberösterreich, 2008