Black locust - Robinia pseudoacacia (Care, Characteristics, Flower, Images, Toxic)

Black locust

Also known as: Locust tree

While the black locust may have a bad reputation in many areas of the US due to its opportunistic and rapid growth, there are benefits to this tree. The black locust is an important food source for honey bees and is a good choice for windbreaks since it grows so quickly (91 to 122 cm per year). Its wood also resists rot, so it is used in fenceposts. The plant is highly toxic, though, and should never be consumed.

Scientific classification

Species

Black locust (Robinia pseudoacacia)

Legumes, milkworts and allies

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Toxic to Human & Pets

Toxicity

Perennial

Lifespan

Tree

Plant Type

Mid spring, Late spring, Early summer

Bloom Time

Late fall, Winter, Early spring

Harvest Time

10 m to 30 m

Plant Height

6 m to 15 m

Spread

Green, Blue, Yellow

Leaf Color

1.6 cm to 1.9 cm

Flower Size

Brown

Fruit Color

White

Flower Color

Green, White, Brown

Stem Color

Winter dormancy

Dormancy

Deciduous

Leaf type

0 - 38 ℃

Ideal Temperature

Rapid

Growth Rate

Images of Black locust

Attributes of Black locust

Growth Rate

With a rapid growth rate, black locust experiences an explosive burst of development in spring, the primary growing season. This quick growth bolsters its leaf production and significantly enhances its overall height. During this period, black locust typically sprouts vigorous shoots, transforming in a noticeable manner. Variances in growth speed across different seasons are minor yet noteworthy, although it primarily thrives in spring. A fascinating example of adaptability, black locust personifies rapid botanical advancement during this time.

Distribution of Black locust

Distribution Map

Although introduced to Europe as early as the 17th century, black locust is native to North America. It's a popularly-cultivated ornamental plant that has been distributed worldwide. In both its native range and elsewhere, it preferentially colonizes disturbed areas and grasslands, and it is thus considered a problematic plant, potentially invasive, in many countries around the world.

Native

Cultivated

Invasive

Introduced

No species reported

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Habitat

Woods, thickets

Hemisphere Trend Curve

Northern

Sorthern

Flowering

Fruiting

Culture

Environmental Protection Value

The black locust has a developed root system, which can conserve water and soil.

Economic Value

It can be used for construction, sleepers, vehicles and agricultural tools; its leaves contain crude proteins and can be used as fodder; its flowers are excellent honey plants, and oil extracted from its seeds are used as raw material for soap and paint.

Garden Use

The black locust is prized for its fragrant flowerheads and burgundy color. It is often chosen for planting in difficult areas where other trees may not grow as well, due to its suckering habit and resistance to pollution. Companion plants for the black locust may include the Blanket flower, Dwarf arborvitae, and Mock orange.

Symbolism

Strength, protection, health

Interesting Facts

The black locust is considered a divine tree and worshipped. In his masterpiece "The Golden Bough", Frazer, a famous British anthropologist, explains why early humans worshipped trees and flowers: "To the savage the world in general is animate, and trees and plants are no exception to the rule."

Name Story

Black locust: As the word "locust" from medieval English was used to describe the tree, it is still used to address the tree till this day. Furthermore, its bark appears to be black gray-colored. Therefore, it is often called the black locust.

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Cultivars

There are several recognized cultivars of Black locust, including the following common varieties :

Locusts 'Hillieri'

Toxicity

All parts of black locust are toxic to humans, with symptoms including stomach pain and diarrhea. Moderately toxic to cats and dogs, causing gastrointestinal upset and weakness. Prompt veterinary care is critical.

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Quickly Identify Black locust

Fragrant white flowers in pendant racemes up to 8 inches long, with pea-like petals in a 'standard,' 'wings,' and 'keel' arrangement.

Smooth, elongated purple-brown pods, 2 to 4 inches long, containing 4 to 8 red-brown kidney-shaped seeds.

Dark blue-green pinnate leaves with up to 23 lance-shaped to ovate leaflets, creating a feather-like appearance.

Sturdy trunk with dark brown to gray deeply furrowed bark, scaly ridges, and branches with short paired spines.

Thick stems with grayish to dark brown color, featuring stout woody texture and branching pattern with short spines.

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Care Guide for Black locust

Every 1-2 weeks

Water

Full sun

Sunlight

0 - 38 ℃

Ideal Temperature

Water: Originating from deciduous woodlands, black locust prefers moist, well-drained soil and should be watered every 1-2 weeks. Its deciduous nature allows it to shed leaves during dry seasons, conserving moisture and enhancing drought tolerance.

Fertilize: Black locust requires balanced fertilizers in spring and high nitrogen before flowering. Monthly feeding promotes healthy growth and blooms, but over-fertilization is detrimental. Adjust formulas seasonally, use liquid fertilizers for beginners, and always water after feeding for optimal nutrient absorption.

Pruning: Black locust is a deciduous tree with fragrant white flowers and thorny branches. Prune in early spring to remove dead or crossing branches, enhancing air circulation and light. Regular pruning reduces suckers and pest risks, promoting structural integrity and an attractive shape.

Propagation: Black locust is a fast-growing deciduous tree propagated from 6-8 inch hardwood cuttings of disease-free parent trees. Plant in well-draining soil and maintain moisture; bottom heat can improve rooting. Once established, black locust thrives with ample spacing, forming dense growth.

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Images of Black locust

Attributes of Black locust

Distribution of Black locust

Culture

Cultivars

Toxicity

Quickly Identify Black locust

Care Guide for Black locust

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