The hedgerow system
A hedgerow is a plantation of trees or shrubs that form a dense and impenetrable line. It consists only of woody plants growing spontaneously in a region. Hedgerows are used to delimit meadows and can be used as firewood, but since the 1990s they have almost disappeared in favour of larger fields. A bocage environment fosters a rich diversity of wildlife. Insects, reptiles, small mammals and lots of birds come to feed and nest there. Various plant species grow in a hedge. They are characteristic of the microclimate and soil type in the region where they are planted.
The aim of hedge laying is to create a new homogeneous fence from a hedge that has lost its effectiveness as an impassable boundary. Bent like wickerwork, the branches form an obstacle to domestic animals, even the smallest ones, allowing livestock to graze. In France, this custom continued until the 1960s, with different techniques depending on the species used or the region: oak and hazelnut in the Morvan, beech in Normandy, hawthorn and blackthorn in the Perche... Hedge laying is also a way of collecting firewood, and this is practiced during the winter period, from November to March. These hedges are safe havens for birds and insects, and help to preserve biodiversity.
A participatory observatory!
The Garden Bird Observatory (L’Observatoire des oiseaux des jardins) is a participatory research programme initiated by the LPO (League for the Protection of Birds) and the Museum. It gathers data that enable researchers to study the distribution of several species in France and the adaptation of urban birds to ever higher temperatures. They also identify the urban developments and management of green spaces that are the least harmful to these species.
When cold weather and food shortages drive some birds into gardens, you can help them with water and suitable food (seeds, fat balls, etc.), but stop feeding them as soon as they can fend for themselves and absolutely avoid feeding them during the breeding season. If you like to observe them, even from your balcony, then go to the website "Oiseauxdesjardins".
If birds can do it, why can't we?
Birds for Change is an action research project in collaboration with MNHN and lnrae. It aims to raise citizens' awareness of waste management and the place of biodiversity in the city. Do you know what corvids are? Crows, ravens, magpies... These birds are among the most intelligent in the animal kingdom, but are still often perceived as pests. What if it was possible to improve how we live alongside them? Faced with the decline of biodiversity and the pollution of ecosystems, a massive and rapid awareness-raising is imperative!
With the help of Bird Box, the role of Birds for Change is twofold:
- to develop a unique awareness-raising solution to reduce waste-related incivilities;
- to improve the image of these birds by raising awareness of the importance of animals and nature in our society.
To find out more, go to the website "Birdsforchange".
A hotel for wild bees and pollinating insects
This "hotel" recreates the various habitats that have become rare in the urban environment and encourages pollinating insects to live there. They stay in the hotel over the winter or lay their eggs there in the summer. In France, there are about 900 species of wild bees:
- Rubicole bees look for plant stems with sufficiently soft pith so that they can easily burrow into them to make their nests.
- Carpenter bees dig up dead wood (branches, unmaintained carpentry).
- Leafcutter bees make their nests in cavities such as wood that has been perforated by other insects, for example wood-eating beetles (wood-eating larvae). The females of some species line their nests with plant fibres or small round pieces cut from leaves.
Monitoring spring pollinator numbers
In the spring, flowers and lots of wild bees appear at different times, depending on the species. But how are they doing in the city? Do they tend to come out earlier because of global warming? Are some species in decline? To answer these questions, it is vital that populations are monitored over several years. There are numerous monitoring programmes for mammals, birds and even plants. The monitoring of wild bees is much rarer. This flowerbed is one of the sites where their populations in Île-de-France is assessed. The selected flowers start to bloom before April and attract pollinators, which are then studied – either in situ or in the laboratory – to determine whether their populations remain stable over the years.
Crows are ringed and closely monitored
Crows live in the countryside as well as in big cities and are concentrated in the green spaces of Paris where they eat our leftovers or dig up lawns to unearth cockchafer larvae. To gain a better understanding of their numbers, movements and behaviour, 852 crows were captured in the Ecological Garden, ringed and then released. Each crow wears three rings: a metal one from the Museum and a coloured one on each leg, featuring a three-digit code. The first results show that few of the crows are sedentary in Parisian parks. Some have been observed near Angers, Reims, and even as far as Bourges. They are so mobile that it would be futile to try to reduce their numbers by regulating them locally; those eliminated would very quickly be replaced by new explorers.
On the website "Corneilles-paris", you can register a ringed bird and view its history.
Vines and their companion plants
Vines were still grown in the Ile-de-France region a century ago. A companion plant adapted itself to these specific cultivation practices. A selection was made that favoured bulbous plants and annuals that grow well in hot weather (some have now found a temporary refuge in the orchards, where the soil is still being cultivated).
At the foot of the vines, vine garlic (Allium vineale), grass lily (Ornithogalum umbellatum), wild tulip (Tulipa sylvestris subspecies sylvestris), muscaris grape (Muscari atlanticum and Muscari comosum) and field gagea (Gagea villosa) push their bulbs into the soil alongside annuals and perennials such as the field marigold (Calendula arvensis), cocklebur (Physalis alkekengi) and clematis aristolochia (Aristolochia clematitis), which occupy a large part of the terrain.
Cereal fields and their companion plants
For almost half a century, the use of herbicides has profoundly changed the rural landscape, leading to the depletion or disappearance of many plant species. Messicolous plants or "harvest companions" are perfectly adapted to the rhythm of traditional cereals, since their annual vegetation cycle follows the alternation of cultivation and harvesting. These plants include poppies (Papaver argemone, Papaver dubium, Papaver rhoeas), cornflower (Cyanus segetum), corn spurry (Agrostemma githago), and harvest chrysanthemum (Glebionis segetum). In this reconstituted environment, only cereals are sown each year, with the messicolous plants regenerating themselves by seeds that have fallen as they ripened.
Consisting mainly of grasses accompanied by a variety of perennial flowers, this meadow has its origins in a traditional agricultural activity: the harvesting of hay for livestock. Annual mowing prevents woody plants, such as trees or brambles, from growing and maintains a dense cover of grass. This natural environment is home to a wide variety of plant and animal species, but it is now in decline in the Île-de-France region. It often only subsists on the edges and embankments of roads. It is also an environmentally friendly alternative to conventional lawns. Easy to maintain, it creates a habitat for biodiversity to develop spontaneously in parks and gardens. Mowing should preferably take place in the autumn, when animals and plants have completed their reproductive cycle. This technique is applied to the meadows at the Versailles-Chèvreloup Arboretum.
The ever-changing wasteland
This evolving 450 m2 wasteland allows the natural process of plant colonisation to be observed. It is divided into three plots that illustrate the evolution of a wasteland from the youngest to the oldest stage. A cluster of plants at a given location is not immutable. As such, once land has ceased to be cultivated, the abandoned wasteland will rapidly develop. It will then evolve more slowly, becoming more of a woodland. If nothing disturbs the process (human intervention, storm, fire, etc.), several stages of colonisation will occur: pioneer plants – mainly annuals – will start to grow, "preparing" the ground for the arrival of herbaceous perennials and shrubs, which themselves precede the arrival of tree species.
La platière, a unique lunar landscape
A typical example of the Fontainebleau massif landscape, the Platières are made up of almost impermeable sandstone bedrock, with a network of small temporary pools and a few, less numerous but broader, permanent pools. These micro wetlands are fed by rain, surrounded by shrubby vegetation (birch, heather) and are generally covered in peaty moorland with acidic pH. Apart from the deepest pools, these environments dry out in summer. Their unusual character allows unique and rare flora to develop. Being so fragile, the alteration of certain factors can cause these wetlands to disappear: drying out due to low rainfall, an increase in the pH of the soil due to nitrate pollution, the progression of the forest (which leads to the environment being invaded by highly dynamic species that cause other species to disappear).
Calcareous grassland (pelouse méso-xérophile)
Like all vegetation, the presence of calcareous grasslands is the result of a combination of soil, climate and history. They grow on thin limestone soil, under intense light and through periods of climatic drought. It is thought that they may be the result of ancient deforestation, followed by grazing or the colonisation of areas that were first cultivated and then abandoned. Although they are clearly declining in France, these grasslands offer a broad range of floristic diversity. They are essentially composed of perennial herbaceous plants that form a carpet of pretty much uncovered grasses, which shelter a huge diversity of flowers, including orchids. These meadows have a high heritage value, with floristic, phytosociological, faunistic and topographical importance.
A mound of earth for burrowing insects
Female spider wasps, solitary bees and digger wasps burrow their nests in wood or soil. Spider wasps and digger wasps are gardeners’ natural helpers and feed their offspring on insects and arachnids; pollinating bees provide their larvae with pollen and nectar. The wood that makes up the mound takes the needs of these insects into account. Due to its simplicity, exposure, shape and size, the bank of sandy earth backed by a stone wall provides ideal conditions for galleries and cells to be excavated for the new generation. But other species can also lay their eggs there: parasitic wasps or flies, whose larvae consume their host’s offspring, or cuckoo species that hog these supplies. This mound offers an inexhaustible wealth of discoveries.
The ruderal grassland
As a result of oak woodland degradation, this kind of scrubland is often found in the vicinity of residential areas, often on an abandoned site. In etymology, "ruderal" means "related to ruins" and, by extension, "to human activities". Soils rich in nitrates and phosphates are proof that there has been quite a significant amount of anthropogenic pollution (dumping, waste, etc.) allowing ordinary vegetation to grow.
Elm, flat maple, sycamore and black locust are the dominant species in this environment. The field elm, which used to be the most abundant tree, has almost disappeared from Europe due to a disease called graphiosis. The species survives in the form of shoots that grow at the foot of old stumps. They are capable of growing up to a few metres tall before being affected by graphiosis.
The oak/ chestnut forest
The oak/ chestnut forest consists of periodically pruned chestnut trees, dominated by free-form sessile oaks. This light forest stands on well-drained, acidic sandy soils of limited fertility. This is very common in the Île-de-France region, particularly on what are known as the "Fontainebleau" sands. The area has relatively few species growing there. The herbaceous stratum is sparse, except for eagle ferns and lily of the valley.
This forest grouping retains a wintry appearance for a long time and few flowers pop up, with the exception of the purple foxglove which flourishes in the clearings. Wood from the chestnut tree is used to make charcoal, fence posts, etc.
The mountain potentilla, which is a protected plant in Île-de-France, grows here.
The oak/ ash forest
The oak/ ash forest is a forest grouping that is characterised by the presence of pedunculate or English oak and common or European ash. It grows on calcareous, rather dry soils and takes the form of a dark coppice with a dense shrub understory. The shrub layer is well developed and features dogwood, viburnum and privet, as well as blue honeysuckle. On the ground, one can find the purple orchid, the hellebore – which blooms from the middle of winter, the male orchid – one of the most common orchids in France, the fetid iris – which only blooms in the light, the wood laurel, and two plants that are protected in the Île-de-France region – the falcaria vulgaris and the asarum or wild ginger, which are on display in the ecological garden.
The European hornbeam and pedunculate oak give this area its name. It is commonly found as a coppice of hornbeam dominated mostly by oak high forest, growing on rich soils that have often been cleared for agriculture. Widespread in Île-de-France, this type of habitat has a sparse shrub understory and a large herbaceous stratum composed of clearly visible flowers that appear in early spring, before the oaks and hornbeams start to bud. These include a number of bulbous plants (wood hyacinth, bifoliate scilla, wild garlic, etc.). In an urban context, this grouping turns into a ruderal grassland, partly due to the presence of walkers who pick the flowers between March and early May.