The purple robe locust is hardy in U.S. Department of Agriculture zones 4 to 8. The roots and seeds of the purple robe tree spread so aggressively that it is considered invasive.

Are locust trees considered invasive?

Black locusts have invasive traits that enable them to spread aggressively. … Black locust produces hanging clusters of very fragrant white flowers in spring. This fast-growing native tree can form colonies and has brittle wood.

How big does a purple robe locust tree get?

‘Purple Robe’ is a medium sized, suckering, deciduous tree that typically grows to 30-40′ tall with an oval-upright habit. It is noted for its attractive compound leaves and pendant racemes of violet purple pea-like flowers.

How fast do purple robe locust trees grow?

Super hardy and drought tough with a brisk growth rate of 2 feet in one year. It’s the perfect summer shade tree. Purple Robe Locust botanical name is Robinia pseudoacacia, an improvement of the native Black Locust tree.

Do locust trees spread?

Controlling either species is a difficult task, considering their rapid growth and, in the case of black locust trees, their ability to spread quickly through self-seeding and root suckers.

What are locust trees good for?

Black locust wood is useful for lumber, paper pulp, posts, and fuel. This clone growing in Hungary is straighter than most trees in North America, where borer insects and heredity typically produce crooked trunks.

Are locust trees bad?

Black locust has just a few pests of concern, and a little observation and vigilance goes a long way. The health and vigor of the trees are important defenses against devastation, as research has shown that good growing conditions are more important than genetic resistance.

Are locust trees messy?

Are honey locust trees messy? While honey locust trees drop both small leaflets from their compound leaves and purple seed pods, these drop around the same time in fall. The resulting mess is rather easy to clean-up, though the small leaflets are a bit difficult to manually rake.

Do locust trees have deep roots?

Honey locusts have strong, deep taproots that extend as far as 20 feet down as opposed to most trees, which only extend 3 to 7 feet beneath the surface However, unlike the classic tap root system, honey locust trees also have profusely branching roots, as is characteristic of heart root systems.

How long do purple robe locust live?

The hardy purple-robe locust can live up to 150 years with proper care in U.S. Department of Agriculture plant hardiness zones 4 through 8.

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Are purple robe locust poisonous?

Its branches can have sharp thorns, although supposedly there are some thornless varieties. An insect called the locust borer can attack the trunk and branches. Another called the locust leaf miner can cause such damage that the leaves turn brown in the summer. … The bark, leaves, and seeds are poisonous if eaten.

Do locust trees have purple blooms?

The Purple Robe Locust, robinia pseudoacacia, is a stunning ornamental that is known for developing, in the spring, swathes of gorgeous pink-purple flowers that resemble wisteria. It is also a great shade tree. A cultivar of the native black locust, it is also known as the Purple Robe Black Locust.

How do you propagate purple robe locust trees?

Cut the stem into 2-inch sections. To remind you which way to plant the cuttings, cut the top of each root section — the part nearest the tree trunk — straight across. Cut the bottoms at an angle. Push the cuttings into the moist sand with the top of the cuttings slightly under the surface of the sand.

Is locust a hardwood?

Black Locust wood is a hardwood with a Janka hardness scale of 1,700 lbf (7,560 N).

Should I cut down black locust?

Mechanical control of black locust is largely ineffective because of the plant’s vigorous re-sprouting ability. Cutting generally increases sucker and sprout productivity. Repeated cutting or mowing may reduce cover, but plants will regrow. … Fire may increase black locust seedling germination and establishment.

What kills locust tree roots?

Option #1: Cut all the honeylocust root suckers at the base and apply a small amount of systemic herbicide, such as Picloram (Pathway or Tordon RTU). Picloram only works on freshly cut stumps.

Are locust trees worth money?

Black Locust wood contains natural organic compounds that resist rot for 100 years or more, which makes these trees an extremely valuable and environmentally friendly tree. It is the perfect wood for fence and deck posts.

Why do locust trees have spikes?

These thorns are thought to have evolved to protect the trees from browsing Pleistocene megafauna, which may also have been involved in seed dispersal, but the size and spacing of them is less useful in defending against smaller extant herbivores such as deer.

What does locust trees look like?

Locust Tree Identification Locust trees grow to between 66 and 98 ft. … The leaves on locust trees are feather-like and pinnately shaped and measure 6” to 14” (15 – 36 cm). The tree leaves have dark-green or light green color, depending on the species. In the fall, the green leaves turn to a stunning bright yellow color.

Why are locust trees dying?

Bark beetles and roundheaded borers may bore into black locust tree branches. Bark beetles can cause the outer tips of branches to die, which is a condition called “flagging.” They mine into the branches up to 6 inches from the tip, causing the end of the branch to die. … The dying branches should be removed and burned.

Does Locust make good firewood?

One lesser-known tree that makes great firewood is black locust. … Not surprisingly, the same density and durability that makes black locust good for fence posts also makes it among the best firewood trees.

Are locust trees good shade trees?

The Shademaster Honeylocust tree provides a lot of shade. Frisia Golden Locust (Robinia Pseudoacacia). Frisia Golden Locust is distinguished by its Golden-yellow bijugate leaves color.

What trees have no invasive roots?

The best trees with non-invasive roots include Adams crabapple, Amur maple, pawpaw fruit tree, American hornbeam, bronze loquat, English holly, Fraser photinia, and the dwarf plum. Some of these trees are small in size and suitable for small yards while others are evergreen shade trees.

Is there a dwarf locust tree?

The umbrella locust tree (Robinia pseudoacacia “Umbraculifera”), also called umbrella black locust or umbrella common locust, is a dwarf cultivar that grows to 20 feet tall.

Which trees cause the most pipe damage?

• Sycamore trees.
• Willows.
• Oak and fig trees.
• Maple trees.
• Aspen trees.
• Elm trees.
• Birch trees.

Are redbud tree roots invasive?

It fits well into small gardens or tight spaces and doesn’t intrude on hardscapes with invasive roots. Redbud does well in parking lots or as a street or sidewalk tree and can grow in raised planters or large containers.

Which trees can be planted close to houses?

• Guava Tree (Psidium guajava) …
• Tamarind Tree (Tamarindus indica) …
• Eucalyptus Tree (Eucalyptus globulus) …
• Lemon Tree (Citrus limon) …
• Curry Tree (Murraya koenigii) …
• Wood Apple/Bael Tree (Aegle marmelos) …
• Drumstick Tree (Moringa oleifera) …
• Neem Tree (Azadirachta indica)

What is dropping from my locust tree?

High temperatures and low moisture conditions may cause locust leaves to turn yellow and drop. Trees naturally respond to limited water by dropping leaves to conserve water. This is enhanced if the hot, dry weather was preceded by a cool, wet spring or late cold spells.

Does purple robe locust have seed pods?

Flowers grow in 4-8” long, hanging clusters and bloom in late spring (May to early June). Flat hanging pods are 2-4” long and contain 4-8 seeds. Pods start out green with purple-brown blotches and dry to a light brown.

Does a locust tree have thorns?

Members of the pea family, locust trees produce large clusters of pea-like flowers that bloom in spring, followed by long pods. … Except for a few thornless honey locust varieties, locust trees have fierce thorns that grow in pairs along the trunk and lower branches.

Are purple robe locust trees toxic to dogs?

Every single part of this plant is toxic to your pet if consumed, so if you think or know your pet ate or chewed on this plant, you should contact your veterinarian. Symptoms as severe as liver damage, convulsions, and respiratory trouble can develop.