Common black locust

Common black locust
Common black locust ( Robinia pseudoacacia )
Systematics
Order : Fabales (Fabales) Family : Legumes (Fabaceae) Subfamily : Butterflies (Faboideae) Tribe : Robinieae Genre : Robinia ( Robinia ) Type : Common black locust
Scientific name
Robinia pseudoacacia
L.

The common black locust ( Robinia pseudoacacia ), also called black locust , white black locust , false acacia , pseudo acacia , common pod thorn or silver rain , is a deciduous tree. It is native to North America and has only been planted in parks and gardens across Europe for almost 400 years. It is now also growing wild.

The common robinia is tree of the year 2020 in Germany.

Taxonomy

Robinia avenue in Stepperg

The black locust is a species of the subfamily of the Pea family (Faboideae) in the family of legumes (Fabaceae).

The black locust is commonly known as false acacia after its species name pseudoacacia . She may be the acacia ( Acacia not particularly related) close, which in turn to the subfamily of mimosa plants include (Mimosoideae), but both are similar in the shape of feathered leaves and thorns . But even the flower shapes are very different. Mixing up species of both genera is almost impossible in Central Europe, as acacias are only native to subtropical and tropical regions and only thrive in very few places in Central and Western Europe with a particularly mild climate.

The species of the genus Robinia ( Robinia ) are almost all shrubs, trees besides Robinia pseudoacacia are only Robinia neomexicana and Robinia viscosa .

It is not always certain to what extent different forms of black locust can be traced back to crossings with other black locust species or mutations. Is known Robinia pseudoacacia var. Rectissima which in 1936 Long Iceland was found. A striking feature of this variety , the status of which is controversial, is a straight shaft that is also developed outdoors. This shape has given it the name "ship mast robinia". Offspring of these trees are in great demand in forest plant breeding.

Origin of name

Robinia inflorescence

Carl von Linné , who scientifically published the genus Robinia for the first time, named it after Jean Robin , the court gardener of the French kings Henry III. , Heinrich IV. And Ludwig XIII.

The scientific epithet pseudoacacia indicates the (misleading) similarity with the acacia. The occasional use of the trivial name Silver Rain is due to the grape-like, drooping white inflorescences of the tree - obviously based on the names of are also included under the butterfly cabbage family trees laburnum (Laburnum) and Wisteria (Wisteria).

description

Appearance (habitus)

Bark of the common black locust

Thorns

The common robinia is a deciduous tree with a rounded or loosely umbrella-like crown, which can grow to heights of 12 to 20 m in the open and 20 to 30 m in the closed stand. The trunk diameter can reach over 1 meter. The rough, thick bark of the trunk is gray to dark brown, deeply furrowed and often longitudinally fissured. The branches are twisted on a short trunk that tends to form a double crown. The tree is largely winter frost hardy .

The common robinia does not green itself until very late in spring. The alternate and imparipinnate leaves are 15 to 30 cm long. They consist of a slightly furrowed rhachis and about 9 to 23 egg-shaped to elliptical or elongated, entire-margined and short-stalked, rounded to indented, sometimes finely-pointed and 2–5 cm long individual leaves . They can fold vertically downwards through small joints when the heat is high ( thermonastia ). There are rapidly sloping, needle-like and meticulous stipelles .

During the inflorescence area and the crown are usually without thorns, which are particularly to the scions Stipules long cm to 3, red-brown colored thorns transformed.

Inflorescences and flowers

Inflorescences

The white, stalked flowers of the common robinia appear from May to June. 10 to 25 of the strongly bergamot-like scented flowers are grouped together in between 10 and 25 centimeters long, pendulous and racemose , axillary inflorescences on the young twigs. The typical butterfly flowers with their green-reddish, hairy calyx offer plenty of nectar and are therefore visited by many insects , including honey bees. In Alsace, locust trees were therefore planted as a bee pasture for "acacia honey". The nectar and the anthers ripen at the same time. If an insect settles on the flower, the first thing that emerges is the scar, which brushes off any pollen that may have been brought with it from the stomach.

Fruits and seeds

Pods ("pods") of the common robinia

Open pods of common robinia

Shells that are strongly flattened, pointed and slightly winged on the abdomen are formed. They are brown, with short stems, about 5 to 12 inches long and 1 to 1.5 inches wide. Its cover is parchment-like leather. There are about 4 to 14 seeds in the inner indentations of the pods . These flattened, red to dark brown, somewhat speckled and slightly kidney-shaped seeds, which ripen in September, are 4 to 7 millimeters long, smooth and very hard-shelled. The sleeve that surrounds them gradually rips open along the back and abdominal seams during winter. Since the fruits or at least seed-containing pod halves sometimes hang on the tree until next spring and are blown away by strong winds, the common robinia is one of the so-called winter dwellers .

Chromosome number

The number of chromosomes is 2n = 20 or 22.

Propagation strategy

The common robinia spreads its seeds by the wind (so-called anemochory ), at least as long as they are still hanging in the pods or pod halves. The spreading distance that the seeds of the plant can overcome in this way is relatively small because of their high weight. The seeds are seldom spread more than 100 meters. Even with wind, single seeds only go to the ground in the immediate vicinity of the mother tree.

Robinia compensates for this disadvantage using two mechanisms. The tree species blooms and produces fruit as early as the age of six and its seeds can germinate for a long time. The period of germination is estimated to be up to 30 years. However, the plants need a lot of sunlight to germinate. These properties determine the pioneering ability of the robinia. Starting from already existing seed trees, the Robinia is very quickly able to cover new open locations; the species has a very strong tendency to feral.

The robinia is also able to reproduce vegetatively through root saplings. This spread, also known as “clonal growth”, is favored when site disturbances such as fires or clearing occur. The common robinia reacts to this with an increased formation of root brood , which ultimately leads to a compression of already existing stands; other species are thereby displaced.

distribution

Natural occurrence

The common black locust is a tree that is native to the Atlantic North America and was widespread in the Appalachian Mountains and the US states of Pennsylvania , West Virginia , Virginia , Kentucky , Tennessee , North Carolina , Georgia , Alabama and Arkansas . It grows there as a pioneer plant in mixed deciduous forests on moderately nutrient-rich sandy and loamy soils at heights of up to 1600 meters. Their natural range is characterized by a humid climate with annual rainfall between 1020 and 1830 millimeters.

Natural range of the common robinia (1938)

Old black locust forest on the juniper heather ( Oberdorla )

As the studies cited by Kowarik show, the common robinia is a tree in its original range that initiates forest regeneration after "catastrophic" disturbances such as forest fires or clearcuts. The newly populated area is dominated by this tree species for about 20 to 30 years, which is then displaced by other tree species such as the tulip tree . The tree species that are able to displace the common black locust in their location are usually characterized by the fact that they grow taller than the black locust and provide a lot of shade. In the forests of the Appalachian Mountains, which have been able to develop undisturbed for a long time, the percentage of black locust is less than 4%.

Distribution area

The undemanding black locust was spread by humans in numerous areas that did not belong to its original range. It is therefore a so-called hemerochore plant and, due to its introduction after 1492 in Europe, is one of the neophytes . Today it can be found in Europe, North Africa, West and East Asia. In North America, too, starting from plantings, it has significantly expanded its range both spatially and spatially. Both in Europe and in the newly populated North American distribution areas, it grows in locations that are much drier than those in its original distribution area.

In the German forests , the black locust comes after the results of the Third National Forest Inventory (2012) with a total of 11,000 hectares in the Hauptbestockung and 9,000 hectares in the Jungbestockung ago, which corresponds to an area ratio of well below one percent. In addition, it is often found in Germany outside the forests as a park and city tree as well as "overgrown" in dry bushes, on fallow land and along railway embankments. In Switzerland, it was included in the black list of invasive neophytes due to its potential for spreading and the damage in the areas of biodiversity , health and economy .

Introductory story in Europe

The common robinia was introduced to Europe as an ornamental plant

According to most sources, black locust was introduced to Europe in 1601 by Jean Robin , the pharmacist and botanist to the kings of France, from Virginia to Paris , where in the Jardin des Plantes and on Place René Viviani in front of the north facade of the church of St Julien-le-Pauvre, not far from Notre-Dame, two specimens planted by Robin are considered to be the oldest trees in the city. The Robinia on Place Viviani with a trunk circumference of 3.90 m is probably the older one. It was damaged by bombing during World War I and then supported by three concrete pillars, but it is still in bloom. The tree is listed in the Directory of Notable Trees of France ( Arbres remarquables de France ).

Because of its attractive inflorescences and pinnate leaves, the common robinia was first planted as an exotic ornamental wood in parks. It came to England in 1640, and the first evidence of cultivation in Germany is available for 1670, when it was planted in the Berlin Lustgarten.

In Italy , the locust was introduced in 1662, the first copy in the Botanical Garden of Padua planted. Seeds from this tree were used in 1750 on behalf of Empress Maria Theresa to introduce the tree to Austria . In 1788, a sprout raised from a seed in Padua was brought into the garden of the Arcispedale di Santa Maria Nova in Florence and then transplanted into the Giardino dei Semplici . The author of the introduction to Tuscany was the doctor and botanist Ottaviano Targioni Tozzetti. Since then the black locust has mainly spread in northern Italy: in Piedmont (approx. 85,000 ha), in Lombardy , in Veneto and in Tuscany.

In the course of the 18th century this type of wood was seen as a promising species for the developing regulated forestry on poor locations. There was regional hope of being able to counteract the shortage of wood that had previously been caused by unregulated overuse , resulting in forest destruction, through the cultivation of the robinia in the short term. More on this in the history of the forest in Central Europe . Two properties favored its rapid spread: the robinia makes only minor demands on the soil, because thanks to the nodule bacteria that bind with nitrogen in the air, it is able to “fertilize” the soil. It is therefore a suitable tree species for the reforestation of forests that have been destroyed by overexploitation, and it is a plant that prevents further soil erosion . It is therefore still used today for planting in sandy areas.

Typical locations in Europe

The common robinia is now cultivated in a targeted manner on a wide range of locations. There is a stronger natural distribution, especially in the areas that are climatically particularly favorable, since the tree is dependent on high amounts of heat in the vegetation period for seed formation . In these areas, it spreads, starting from plantings, along the edges of forests and traffic routes to fallow land and urban industrial locations. It also penetrates sites such as dry sand and lime grasslands and displaces the species that grow there.

The common robinia also spread widely on rubble areas after the Second World War . The destruction and the subsequent lack of maintenance on many properties led to the creation of large areas overgrown with robinia in cities such as Leipzig , Berlin , Stuttgart and Cologne .

In some areas of Hungary and Slovakia , the black locust is now the most important forest tree, with cultivated forms that are more straight-stemmed than the original species are preferred. The common robinia is also grown on a very large scale in South Korea .

Worldwide, the area under cultivation increased from 227,000 to 3,264,000 hectares between 1958 and 1986 , which is more than tenfold. After poplar and eucalyptus, the black locust is the most common deciduous tree cultivated in plantations worldwide.

Forestry Economically, the black locust is depending on anthropogenically induced Susceptibility all the more important because, as a legume is capable of atmospheric nitrogen by means of symbiosis with her living nodule bacteria bind. In low-nitrogen locations, this tree species therefore has a competitive advantage over other species, which, among other things, can lead to a higher wood yield of the robinia compared to pine or oak .

use

Use of wood

The widespread distribution that the robinia has meanwhile found is due to the economic use of its wood.

The wood, which is resistant to wood rot, is flexible, strong and extremely hard at the same time ( Brinell hardness 46 N / mm²). It is used in shipbuilding and furniture construction, as pit timber, as threshold timber, in traditional arch construction and in agriculture (e.g. viticulture: stickel ). It is considered to be more resilient and durable than oak . Since it remains stable for a long time when used outdoors, even without chemical preservation treatment, it is well suited, for example, for the construction of devices in children's playgrounds and garden furniture. In addition, it is often used as part of protective forest restoration for temporary construction . Snow rakes and tripods are often built from this wood.

Since robinia wood is a good substitute for tropical woods due to its properties , it is currently widely planted.

The robinia provides rich nectar and is therefore important for beekeeping as a bee forage plant

Mining

Robinia wood was used in mining to support the tunnels. Robinia reaches the dimensions prescribed for pit punches at an age of 20 years, compared to 30 to 40 years for pine . However, robinia wood never played a major role in mining. Even in the home of the black locust, the USA, the consumption in 1923 was only 6997 m³, less than one percent of the total consumption. Today, at least in Germany, robinia wood is no longer used in industrial mining.

Numerous tests have also been carried out in Germany to determine its suitability as pit timber . As early as 1900, the Saarbrücken mining directorate reported on experiences with robinia wood, in which it was still completely healthy after two years, while oak wood was already rotting in its outer parts.

Reports from Hungary that built-in robinia wood smelled so unpleasant that it was not possible to work in its vicinity were probably based on the coumarin released from glycosides (see toxicity ), among other things . Robinia root wood, in particular, has an unpleasant odor that it retains for a long time.

Robinia wood (above under normal lighting) fluoresces inside with ultraviolet irradiation (below), presumably due to there by decomposition of glycosides freed coumarins

Robinia wood can have a certain "warning capacity". This is understood as the property of the wood to splinter before breaking and to emit audible warning noises to the environment, which enables the miners to react in good time. However, this property is more pronounced in softwoods that break with long fibers. In return, robinia beams bend sharply before breaking, which gives an additional visual warning.

The difficulty in processing robinia wood is seen as a disadvantage. Robinia stamps are heavier than those made from other types of wood. Plus, they're harder to work with and to nail .

Bee pasture

As an important early summer crop, the common robinia is one of the so-called bee pasture plants . Robinia blossoms provide a lot of nectar with a high sugar content between 34 and 59 percent. A single black locust blossom produces nectar with a sugar content of 0.2 to 2.3 milligrams in 24 hours. On average, honey yields between 0.66 and 1.44 kilograms can be achieved per tree and flowering season. Because of their high sugar value , locust trees are occasionally planted specifically by beekeepers as a foraging plant. - The honey, which is sold under the name “ acacia honey ”, has a light, slightly yellowish color, is very fluid and crystallizes very slowly over the course of several years in the form of a sediment. The slow crystallization is due to the high proportion of fructose , since fructose in honey has little tendency to crystallize in contrast to glucose, which is predominant in many other types of honey .

The countries in which it is used very intensively as a beekeeping plant in addition to forestry include France and Hungary. In Brandenburg , too , the robinia makes up to 60 percent of the honey harvest in good years.

Use as an ornamental plant

Robinias are still used as ornamental plants. For this reason, a number of cultivars have now emerged. The common robinia is often used as an avenue and city tree. It tolerates the dry urban climate very well and is insensitive to smoke , dust and soot . In the opinion of the Central Horticultural Association , however, planting within reach of endangered types of vegetation and open land biotopes, especially in the case of poor grassland , should be avoided.

Use as food

The flowers are non-toxic, they can be made into jam or syrup or used in teas and drinks.

In parts of Austria where the tree is called acacia , the flowers are baked in batter to make so-called acacia grapes.

Toxicity

The whole plant is considered highly poisonous, especially the bark and the fruits; Because of its toxicity, especially for horses, robinia wood must not be used in the construction of boxes in the stables. The flowers are not poisonous.

Main active ingredients

• in the bark about 1 to 6% robin , phasine , syringin , 2 to 7% protocatechin
• in the leaves of indican , asparagine , kaempferol and acacetin
• in the seed lectins

Symptoms of poisoning, immunobiological effects

Robin and Phasin are very poisonous. Like other toxalbumins, both substances are real antigens and have an agglutinating effect on red blood cells and destroy tissue; when heated, the toxicity of the robin is lost. Natural immunity to these antigens is also possible. Vomiting, lethargy, mydriasis, and convulsive twitching can occur within an hour . In horses there are first states of excitement, then apathy and at times convulsive twitching. 150 g of robinia bark can be a lethal dose for horses.

The consumption of seeds and the chewing of the roots have occasionally resulted in poisoning, some of which are fatal. Poison control centers report on cases in which symptoms of poisoning in the form of nausea occurred after ingestion of four to five seeds, but 30 seeds - then probably swallowed whole - were tolerated without symptoms.

Effects on the mucous membranes

The pollen of black locust is one of the hay fever -Erregern. Its importance as an inhalative allergen is overestimated, however, since the pollen grains are only carried short distances by the wind and only find their way to the mucous membranes in the direct area of ​​the black locust trees or groups of black locust trees.

Ecological Significance and Hazard Potential in Europe

Robinia pseudoacacia 'Frisia'

Part of the cultural landscape

Due to its properties as a road salt and emission-resistant tree species, the black locust is a valuable tree that is often better suited than native species for greening difficult urban-industrial locations. Cultural and historical aspects can also speak in favor of planting. The invasion biologist Ingo Kowarik also spoke out in favor of the further planting of locust trees:

“Robinia has been a defining element of historical cultural landscapes in various areas since the 18th century. In Brandenburg she refers u. a. on the traditional use of plants in historical gardens, on early landscaping and on plantings as bees, for erosion protection and as corridor wood or forest tree ... In many villages and cities it is a traditional ornamental and street tree . "

- Kowarik, p. 165

The oldest locust tree in Germany is in the Branitz Park .

The robinia forests that arose immediately after the destruction of Berlin are of historical testimony value. Benesperi et al. report, however, that such forests, which are dominated by black locust trees, are characterized by species poverty and the dominance of nitrogen-loving plants.

Problem: invasive plant

Although the black locust tree is a popular tree species in forestry and represents an alternative to imported tropical wood, it is viewed as a problematic neophyte that can threaten the biodiversity of certain locations. In some places the black locust has become an invasive plant species. "The reason for this is its ability to symbiotic nitrogen fixation, which has a fertilizing effect and can lead to a change in the species composition at certain locations. As a result, rare biotope types such as grasslands , limestone grasslands and dry sandy grasslands are particularly threatened. The black locust can penetrate dry slopes, but also in near-natural Central European forest stands. In Hungary, for example, in the Kiskunság National Park, it endangers the dry grasslands characteristic of this area , and in Austria 30% of the important dry grass stands are threatened by this tree species among others the nature reserve Mainzer Sand , the Sandhausen dunes , the Spitzberg near Tübingen , the Mansfeld Hügelland and the Badberg in the Kaiserstuhl .

Robinia pseudoacacia 'Umbraculifera'

Studies cited by the invasion biologist Ingo Kowarik show that black locust growth in such locations very quickly and significantly reduces the diversity of species and that the range of species is shifting towards non-endangered and widespread species. This goes hand in hand with a strong change in the spider and ground beetle fauna . Indigenous pioneering plants such as sloe and sand birch threaten such locations, but the transition to the forest is much slower. In the case of robinia, however, the expansion and compression of the stands takes place very quickly, mainly because of the vegetative growth via root shoots, and under older robinia a dense shrub layer usually forms, which consists mainly of black elder . Robinia stands therefore resemble closed beech forests in terms of their light conditions on the ground.

In its natural range, insect damage and the growth of shade wood species ensure that the robinia is replaced as the dominant tree species after around 20 to 30 years and a more mixed forest structure gradually sets in. In contrast, there is no such succession in the black locust stands in Central Europe - the conversion of a black locust tree into a maple forest , which was assumed in the 1960s, has not yet been confirmed. Both the 60 to 70 year old stocks at the Kaiserstuhl as well as the somewhat younger Berlin black locust forests suggest that locust populations are much more permanent here than in their original area of ​​distribution. The black locust is therefore to be assessed as an "invasive" neophyte and is included on the warning list of invasive vascular plant species in Germany by the Federal Agency for Nature Conservation . Results of niche-based forecast models suggest that the Robinia could spread significantly further in view of global climate change in Central Europe, including in Natura 2000 protected areas.

Man as the cause of the spread of the black locust

Robinia in a front garden in Ferchesar , Havelland

The black locust populations, from which rare types of biotope are threatened, can mainly be traced back to plantings. While the giant hogweed, for example, very quickly reaches new areas along open land areas and flowing waters due to the driftiness and swimming spread of its diaspores , with the common robinia humans first have to colonize an area by planting a seed tree. The strong increase in urban areas after the Second World War was only possible because locust trees had already been planted there as ornamental trees.

Control of black locust trees as part of nature conservation

The removal of established black locust stands is very time-consuming and must be limited to the locations where this is urgent for nature conservation reasons. Even after the successful removal of robinia, a change in the biotope has taken place due to the nitrogen enrichment of the soil, so that, for example, the original grassland vegetation cannot arise again.

Control measures are sensible and effective where black locust stands are close to biotope types that are endangered by them and where there is a risk that they will overgrow them without further intervention. Control is difficult because the robinia can both kick out of the hive and also form root runners. As experience in individual nature reserves has shown, a simple felling of the trees only leads to the formation of denser stands. In the USA, the herbicide Roundup is often used to control robinia after clearing . More gentle and also more successful than felling, but more time-consuming, is a procedure used in Berlin's nature reserves, which is known for forestry as ringing . With the exception of a narrow bar, the bark is removed from mature trees in a wide band during the summer. Unlike usual, the trees do not react to this damage by developing root sprouts. The remaining bridge will be removed next spring. The tree can be felled two years after the ringing, before it falls out again as in simple felling.

Predators and parasites

The black locust is attacked by the white berry mistletoe , both in Europe and, after its introduction there, in North America. Over a hundred different types of mushrooms live on or in the wood of the robinia in North America, but many also in Europe. In southern Germany, for example, 69 wood-dwelling fungi were found on robinia, of which 43 were parasitic such as the sulfur pore or the flat pear pear . The Phomopsis oncostoma fungus produces a tree canker .

The gall mite Obolodiplosis robiniae lives exclusively on the black locust and is also spreading rapidly in Europe.

Robinia leaf miner larva in an open mine on a black locust leaf

In the meantime, the black locust leaf miner and the mining Parectopa robiniella have established themselves in Europe as a neozoon that specializes in the common black locust . The caterpillars of the robinia leaf miner only use the leaves of this tree as a feeding plant. In 1983, this insect, which is actually native to North America, was first discovered near Basel . From there it spread very quickly to the rest of Europe. In 1988 the first finds were reported in Germany , France and Italy , and since the 1990s finds have also been reported in Hungary , the Czech Republic , Slovakia and Poland . This caterpillar hardly has any predators in its new habitat, and its speed of spread has increased significantly in recent years. So far there is no detailed knowledge of how much it can damage the trees.

literature

• Eugen Vadas: The monograph of the black locust. With special consideration for their forestry importance. Joerges, Selmecbanya 1914.
• Kurt Göhre (Ed.): The Robinia and its wood. Deutscher Bauernverlag, Berlin 1952.
• Ulrich Hecker: BLV-Handbuch Trees and Shrubs. BLV, Munich 1995, ISBN 3-405-14738-7 .
• Ingo Kowarik : Biological Invasions. Neophytes and Neozoa in Central Europe. Ulmer, Stuttgart 2003, ISBN 3-8001-3924-3 .
• Angelika Lüttig, Juliane Kasten: Rose hip & Co. Flowers, fruits and spread of European plants. Fauna, Nottuln 2003, ISBN 3-935980-90-6 .
• Mario Ludwig , Harald Gebhard, Herbert W. Ludwig, Susanne Schmidt-Fischer: New animals and plants in the natural environment. Recognize and identify immigrant species. BLV, Munich 2000, ISBN 3-405-15776-5 .
• Ruprecht Düll , Herfried Kutzelnigg : Pocket dictionary of plants in Germany and neighboring countries. The most common Central European species in portrait. 7th, corrected and expanded edition, Quelle & Meyer, Wiebelsheim 2011, ISBN 978-3-494-01424-1 .
• Lutz Roth, Max Daunderer , Kurt Kormann: Poison Plants - Plant Poisons. 6th edition, Nikol, Hamburg 2012, ISBN 978-3-86820-009-6 .

Web links

Commons : Ordinary black locust  album with pictures, videos and audio files

• Common black locust. In: FloraWeb.de.
• Common black locust . In: BiolFlor, the database of biological-ecological characteristics of the flora of Germany.
• Profile and distribution map for Bavaria . In: Botanical Information Hub of Bavaria .
• Robinia pseudoacacia L. In: Info Flora , the national data and information center for Swiss flora . Retrieved November 18, 2015.
• Thomas Meyer: Data sheet with identification key and photos at Flora-de: Flora von Deutschland (old name of the website: Flowers in Swabia )
• Profile in the NeoFlora internet manual
• On the toxicity of the silver rain (Robinia pseudoacacia)
• Martin Wolfangel: Invasive alien plants - a threat to biological diversity
• Richly illustrated short description on garten.cz, accessed on November 14, 2016.

Individual evidence

1. ↑ Common Schotendorn as the regional name for the Robinia ( Memento from January 1, 2013 in the Internet Archive ) accessed on June 15, 2014.
2. ↑ The Common Robinia (Robinia pseudoacacia) Tree of the Year 2020 - 32nd YEAR TREE
3. ↑ Beautiful and unusual (in Robin Wood magazine, No. 143 / 4.19). (PDF) The Robinia is Tree of the Year 2020. www.robinwood.de, 2019, accessed on December 1, 2019 (German, pages 22 - 27). 
4. ↑ For example in southern Ticino and in the south-west of England. There acacia (may Acacia ) are cultivated not only gardening, but also occasionally run wild or even establish. Konrad Lauber, Gerhart Wagner: Flora Helvetica . 4th edition. Haupt-Verlag, Bern / Stuttgart / Vienna 2007, ISBN 978-3-258-07205-0 , p. 578 No. 1080 a : "Acacia dealbata: Wildering in the southern TI." - David Aeschimann, Konrad Lauber, Daniel Martin Moser, Jean-Paul Theurillat: Flora alpina. An atlas of all 4500 vascular plants in the Alps . tape 1 . Haupt-Verlag, Bern / Stuttgart / Vienna 2004, ISBN 3-258-06600-0 , p. 816–817 (marked in the distribution map for the canton of Ticino and the province of Como.). - Clive Stace: New Flora of the British Isles . 2nd Edition. Cambridge University Press, Cambridge u. a. 1997, p. 398 (English): “Acacia melanoxylon: grown for ornament; locally +/- naturalized in South Devon and Scillies. - Other species: A few species are grown for ornament in SW England and may sometimes spread very locally by suckers or produce young seedlings, but are not truly naturalized. " - These places correspond roughly to winter hardiness zone 9 in Andreas Roloff, Andreas Bärtels: Flora der Gehölze. Purpose, properties and use . 2nd Edition. Eugen Ulmer, Stuttgart 2006, ISBN 978-3-8001-4832-5 , pp. Map on the front flyleaf . Acacias are not dealt with in this book because they are not “viable” in German-speaking countries (foreword, p. 7). In France, accordingly, nine Acacia species are specified for the coastal areas of Provence and Corsica: Jean-Marc Tison, Bruno de Foucault, Société botanique de France: Flora Gallica. Flore de France . 1st edition, 2nd printing (with numerous corrections). Biotope Éditions, Mèze 2014, ISBN 978-2-36662-012-2 , p. 708-709 (French).
5. ^ Erich Oberdorfer : Plant-sociological excursion flora for Germany and neighboring areas. 8th edition. Verlag Eugen Ulmer, Stuttgart 2001, ISBN 3-8001-3131-5 , pp. 600-601.
6. ↑ F. Kroiher, A. Bolte: Nature conservation and biodiversity in the mirror of the BWI 2012. In: AFZ-Der Wald. 21/2015.
7. ^ Federal Office for the Environment FOEN: Invasive Alien Species . ( admin.ch [accessed on August 6, 2019]).
8. ↑ S. Buholzer, M. Nobis, N. Schoenenberger, S. Rometsch: List of the alien invasive plants of Switzerland . Ed .: Infoflora. ( infoflora.ch [accessed on August 6, 2019]).
9. ^ Jacques Hillairet: Dictionnaire historique des rues de Paris . Éditions de Minuit , Paris 1985, ISBN 2-7073-1054-9 , p. 452.
10. ↑ Robert bourdu: Arbres de mémoire: Arbres remarquables en France. Éditions Actes Sud, 1998, p. 23
11. ↑ Sandro Pignatti: Flora d'Italia , Volume 1, Edagricole Verlag, Bologna 1982, reprint 2017, ISBN 978-88-506-5242-6 .
12. ^ Antonio Targioni-Tozzetti, Cenni storici sulla introduzione di varie piante nell'agricoltura ed orticoltura tuscan , Tipografia Galileiana, M. Cellini e C., Florence 1853. On the Internet: Antonio-Targioni-Tozzetti: Cenni storici sulla introduzione die varie piante nell 'agricoltura ed orticoltura toscana. Google Books, p. 247 , accessed May 2, 2018 . 
13. ↑ La selvicoltura della robinia. Retrieved May 2, 2018 . 
14. ^ Information from science / from LWF-aktuell No. 20 (PDF) of the Bavarian State Institute for Forest and Forest Science, 1999, p. 13.
15. ↑ Kurt Göhre: The Robinia and its wood. Pp. 265-266.
16. ↑ Josef Lipp u. a .: Handbook of Apiculture - The Honey. 3. Edition. Ulmer, Stuttgart 1994, ISBN 3-8001-7417-0 , p. 38.
17. ↑ Josef Lipp u. a .: Handbook of Apiculture - The Honey. 3rd edition, Ulmer, Stuttgart 1994, ISBN 3-8001-7417-0 , p. 17 f.
18. ↑ Josef Lipp u. a .: Handbook of Apiculture - The Honey. 3rd edition, Ulmer, Stuttgart 1994, ISBN 3-8001-7417-0 , pp. 90 f., 72 ff.
19. ↑ Dealing with invasive species - Recommendations for gardeners, planners and users ( memento of October 2, 2013 in the Internet Archive ), accessed on June 15, 2014.
20. ↑ Elder and acacia grapes. In: Youth Houses. State government of Styria, accessed on May 11, 2020 . 
21. ↑ Ways to understand nature Plant use at riding stables and riding facilities. Information brochure of the Chamber of Agriculture NRW, p. 11 f., Accessed on February 27, 2013 (PDF; 111 kB).
22. ↑ The oldest black locust tree in Germany is in the Branitz Park
23. ↑ Forest plant diversity is threatened by Robinia pseudoacacia (black-locust) invasion (abstract in English) accessed on June 15, 2014.
24. ↑ Wink, van Wyk, Wink, Handbook of poisonous and psychoactive plants, Wissenschaftliche Verlagsgesellschaft mbH 2008, ISBN 978-3-8047-2425-9 , p. 207
25. ↑ I. Kleinbauer et al .: Climate change might drive the invasive tree Robinia pseudacacia into nature reserves and endangered habitats . In: Biological Conservation. Vol. 143, No. 2, February 2010, pp. 382-390, Elsevier
26. ↑ Nadine Zeller: Heat and drought-resistant forest: Looking for great trees . In: The daily newspaper: taz . September 20, 2019, ISSN  0931-9085 ( taz.de [accessed September 24, 2019]).
27. ↑ The Robinia: Evaluation of control measures after 20 years of Robinia research ( Memento from November 26, 2013 in the Internet Archive )
28. ↑ Robinia pseudoacacia ( Memento from May 26, 2014 in the Internet Archive ) accessed on June 15, 2014.
29. ↑ ^{a b c d} Arne Cierjacks, Ingo Kowarik, Jasmin Joshi, Stefan Hempel, Michael Ristow, Moritz von der Lippe and Ewald Weber: Biological Flora of the British Isles: Robinia pseudoacacia . In: Journal of Ecology . tape 101 , 2013, p. 1623-1640 , doi : 10.1111 / 1365-2745.12162 .

This article was added to the list of excellent articles on August 3, 2005 in this version .