Robinia and acacia are often confused with one another. The reason for this is often that the robinia is colloquially called false acacia, which suggests a close relationship between the two plants. But this is a fallacy. Although the two types of plants look similar at first glance, there are a number of differences that can be identified that help distinguish between black locust and acacia.
Distinguish between robinia and acacia
From a botanical point of view, the term "Robinia" is the shortened form for the common robinia. Its scientific name, Robinia pseudoacacia, which is often misleading, already suggests another slang term for the tree, namely false acacia. In addition to these names, however, the designations are also used for the tree
- White locust
- false acacia
- Common podthorn
- silver rain
used. According to the botanical systematics, the common black locust is a species of the genus Robinia, which belongs to the subfamily of the legume family (Faboideae) from the legume family (Fabaceae).
The real acacia (Acacia pulchnella), also called moss thorn, is also a shrub from the legume family. Like the robinia, the real acacia is also an independent plant species. The plant genus is Acacia (Acacia) with around 1,300 species from the subfamily of the mimosa family (Mimosoideae). In other words, the two plants are related, but not particularly close.
Robinia pseudoacacia, black locust
differences
The botanical classification of robinia and acacia is a good way of describing their relationship, but it is of little help in distinguishing between them in nature. Therefore, visible characteristics must be used, such as growth or flowering, to which the differences can be determined.
growth
Black Locust
- deciduous tree
- rounded or umbrella-like crown
- Growth height when free: 12 to 20 meters
- Growth height in a closed stand: 20 to 30 meters
- short stem
- Tendency to double crown
real acacia
- evergreen shrub
- Growth height: 0.5 to 1.5 meters (rarely up to 3 meters)
- axillary mostly one to two spines with a length of 2 to 20 millimeters
acacia
bark
Black Locust
- grey-brown to dark brown bark
- Bark with deep furrows
- netted-longitudinally fissured
real acacia
- hairy or glabrous bark (depending on the variety)
leaves
The leaves of robinia and acacia can be distinguished by the following feature: The robinia leaf consists of an odd number of individual leaves, each of which is located at the end of the petiole. The acacia, on the other hand, has several leaves arranged symmetrically on a petiole.
Black Locust
- alternate
- unpaired
- feathered
- Length: 15 to 30 centimeters
- 9 to 19 uniform single leaflets form a leaf
- can fold down in high heat
- Greening only in late spring
acacia
- alternate
- doubly pinnate
- Petiole: 0.5 to 6 millimeters
- leaflets of the first order: 1 to 15 millimeters
- second-order leaflets: 1 to 6 millimeters
- Length of stipules: 3 millimeters
blossom
Black Locust
- Flowering period: May to June
- hanging, racemose inflorescences with 10 to 25 individual flowers
- Length of inflorescences: 10 to 25 centimeters
- strongly scented
- Flower color: white
Black locust with white flowers
acacia
- Flowering season: winter and spring
- rudimentary racemose total inflorescences with 10 to 40 partial inflorescences
- Flower color: golden yellow
fruit
Black Locust
- red-brown "pods" with a short stem
- Length: 5 to 10 centimeters
- Width: 1 centimeter
- Parchment Leather Case
- Inside four to twelve seeds
- Seed maturity: September
- can get stuck on the tree over the winter (winter stayers)
acacia
- narrow legume
- Length: 1.5 to 5 centimeters
- Width: 0.3 to 0.5 centimeters
- thick margin (hairy or hairless)
- fire germ
Silver Acacia
Another acacia species is often offered in Germany. This is usually the silver acacia, bot. Acacia dealbata. Silver acacias differ from real acacias in their growth, because they grow as a tree. The bark is smooth and rough. The tiny leaves are covered with fine white hairs, giving the tree a silvery appearance. There are also differences in the growth height of the different varieties of silver acacia. "Lisette" reaches a growth height of between six and ten metres, while the growth height of "Rustica" is between four and five metres.