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Toxic to dogs. The ASPCA lists locust (robinia) as toxic to dogs. Top tier among the trees in this database. Any bark, pod or seed eating deserves an immediate call, and breathing difficulty or bloody diarrhea means an emergency clinic, not a phone queue.
Black locust and its Robinia relatives are the tough, fragrant trees of fence rows and pastures: fern like leaves, hanging white spring blossom, and long flat seed pods that litter the ground into winter. The ASPCA lists locust as toxic to dogs, and its parts list, bark, leaves and seeds, reads like an inventory of what a dog can reach.
Look for a medium tree with deeply furrowed bark, feathery compound leaves, hanging clusters of sweet smelling white flowers in late spring, and flat brown pods that persist and drop for months. Young trees and suckers often carry paired thorns. After storms, bark strips and broken branches are the fresh hazard on the ground.
The ASPCA names the toxic principle of locust (robinia) as Toxalbumins: phasin, robin and robitin, in the bark, leaves and seeds. Locust trees arm their bark, leaves and seeds with toxalbumins, protein toxins in the same broad family as the ricin of castor bean, though locust poisoning in dogs usually plays out through the gut and general collapse rather than the castor pattern. The ASPCA sign list is a whole body one: vomiting, depression, appetite loss, weakness, breathing difficulty, bloody diarrhea and death. This is a tree whose chewable parts, bark strips and seed pods, are exactly what dogs pick up.
The clinical signs the ASPCA lists for locust (robinia) are: vomiting, depression, loss of appetite, weakness, difficulty breathing, bloody diarrhea and death. Pod season is the long risk. The flat pods fall, dry, and get carried around by dogs as natural chew sticks, and the seeds inside them are a named toxin source. The second route is storm and fence work: locust posts, bark and pruned branches left in a pasture or yard get gnawed by bored dogs, and puppies teethe on bark strips. Vomiting and depression that progress to weakness or bloody stool after yard time under a locust tree should be reported with the tree named.
Most dangerous part: The bark and the seeds, with the leaves behind them, as the ASPCA itself locates the toxalbumins. Fallen pods and stripped bark from storm damage are the ground level supply.
Locust also names the honey locust, Gleditsia, a different tree that is not this entry, and the confusion matters because owners clear the wrong tree in their minds. This page covers Robinia, the black locust group, identified by the furrowed bark, white blossom and flat pods. A photo of bark and pods together settles the identification faster than any common name.
Call your veterinarian, the ASPCA Animal Poison Control Center on (888) 426-4435, or the Pet Poison Helpline on (855) 764-7661 right away, even if your dog looks fine. Some poisons take hours or days to show their worst effects. Do not make your dog vomit unless a veterinarian tells you to, and keep the packaging, a photo, or a sample of what was eaten to show the clinic.
Rake and bin fallen locust pods from dog yards through the dropping season, and remove storm stripped bark and branches the day they fall. Do not use locust branches as fetch sticks or firewood within a dog's chewing reach, and fence young thorny suckers out of puppy areas.
For a fast, tough shade tree in a dog pasture or yard, there is no locust substitute to recommend blindly: verify candidate trees on the ASPCA list by scientific name, and remember that bark and pods, not just leaves, are the parts to vet for any tree a dog lives under. Whatever you plant next, check it on the toxic plants index approach: confirm the plant on the ASPCA toxic and non-toxic list under its scientific name, Robinia spp. is the name to avoid here, before it goes in the ground or on the shelf.
Yes. The ASPCA lists locust (robinia) (Robinia spp.) as toxic to dogs. Its toxic principle is Toxalbumins: phasin, robin and robitin, in the bark, leaves and seeds, and the signs it lists include vomiting, depression, loss of appetite, weakness, difficulty breathing, bloody diarrhea and death.
Call your veterinarian, the ASPCA Animal Poison Control Center on (888) 426-4435, or the Pet Poison Helpline on (855) 764-7661 straight away. Note what part of the plant was eaten and roughly how much, keep any remaining plant material to show the clinic, and do not make your dog vomit unless a veterinarian tells you to.
The bark and the seeds, with the leaves behind them, as the ASPCA itself locates the toxalbumins. Fallen pods and stripped bark from storm damage are the ground level supply.
No. The seeds inside the pods are one of the three parts the ASPCA names for the toxalbumins, and the pods are the part dogs most often carry and chew. Take pods away and offer a proper chew instead.
They are different trees in different genera. This page and the ASPCA listing cover Robinia, the black locust group. Honey locust is Gleditsia. Because the names overlap, identify by bark, blossom and pod, or by photo, before deciding what your dog ate.
This page is general information drawn from the published guidance of the organizations listed under Sources below. It is not veterinary advice, and it does not replace your own veterinarian, who knows your dog. If your dog has eaten something toxic, contact your veterinarian, the ASPCA Animal Poison Control Center on (888) 426-4435, or the Pet Poison Helpline on (855) 764-7661 straight away. A consultation fee may apply on the helplines.
Last updated: November 2026. Every verdict on this page was checked against the sources listed above. How we work: our methodology.
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