Jim Bradshaw: Was Mamou tea a cure or a killer?

There was at least a minor hullabaloo in spring 1941, when health officials in Washington  made the claim that the Mamou plant widely used in south Louisiana to make a herbal tea could kill you.
The recipe for the tea made from the Mamou plant, Erythrina herbacea, still probably the best known of Louisiana’s medicinal plants, was handed down in old families on the Louisiana prairies, and was a staple used by traiteurs.
It got its Cajun  name because it grows naturally on the prairies and was particularly prevalent on Prairie Mamou, the area is between Bayou des Cannes and Bayou Nezpiqué,
On old maps, the place name appears as Prairie Mammouth,  probably named for bison that once grazed there. Early Acadian settlers used the word to mean any big animal.
Each spring the Mamou plant shows off bright crimson flowers loved by hummingbirds, butterflies, moths, and bees, and pods full of  red beans that people used to make a tea to treat colds, the flu, bronchitis, and whooping cough.
Native Americans in Texas and Louisiana used the red beans to make jewelry. People in south Louisiana also used them to make rosaries.
The argument wasn’t about the rosaries.
It was about the tea, and about the bulletin sent by the feds to health units in South Louisianan claiming that  it was actually bad for you, potentially lethal.
The response by St. Landry planter R. L. Walker in a letter to the newspapers that April was typical.
“These reports in effect say that our old friend the Mamou bean can no longer be placed in polite society and used to cure or help cure our coughs and colds. … If Mamou cough remedies prepared in my own home since I was a child and used consistently by my family were poisonous, I know I would be dead because I have taken it as needed by the gallons. Other members of my family have done likewise.,” Walker said.
He said he was neither a scientist or a mathematician, “but I don’t hesitate to say that over 75 percent of  … [South Louisiana residents] would have died already because Mamou preparations are consistently used, have been consistently used for generations. … If the Mamou bean and syrups made from it have poisoned 75 percent of our population … then 45,000 [St. Landry] residents are dead, but somehow … continue to walk around, make a living, and eat three meals a day,”  Walker concluded.
It turns out there was a bit of over-reaction on both ends of the debate.  
The health warning was correct. The beans themselves should not be eaten.
The U.S. Geological Survey list of Louisiana plants, labels them as poisonous.
They contain a powerful alkaloid that affects the motor nerves, and are used in Mexico to poison rats. The LSU AgCenter says that “all parts of the plant are mildly toxic but have medicinal qualities also that must be tapped into with caution.” Note: With caution.
A culinary podcast warns, “While some parts of the coral bean plant have been used in traditional medicine ..., it is not recommended for consumption by humans. The plant contains toxic compounds, particularly in its seeds and bark, that can cause severe gastrointestinal distress if ingested.”
Nonetheless, people across south Louisiana made Mamou tea and swore by it. Before he came up with his Hadacol cure-all, Dudley LeBlanc briefly marketed “Dixie Dew Mamou,” a cough tonic that used the toxic bark as its base. 
The tonic also contained alcohol, chloroform, oil of peppermint, distilled pine oil, oil of eucalyptus, and menthol syrup, among other things. If it killed you, it wouldn’t be just from Mamou bark.
A mild tea made from just a few beans was probably less toxic than Dudley’s alcohol-chloroform blend, and the tea would not have been so popular and used for so long if it did not kill the cough without killing the patient.
Most people who grow Mamou plants now do it for the hummingbirds and the pretty flowers, not to make the tea — and despite Mr. Walker’s letter of protest, I suggest that keeping it for the birds is a pretty good idea.
According to the AgCenter, the perennial plant likes full sun  It prefers well-drained soil but can tolerate wet feet for short times, Give it room. It can grow  up to ten feet tall, though four to six feet is more common. As it matures, it will come back wider each year, potentially spreading to 20 feet across. It has no serious pest or disease problems. A borer moth will sometimes cause it to die back, but usually will not kill the plant.
And remember, if left for the birds and the bees, the plants will make them happy, not kill you, and provide a regular supply of beads for your rosary.
You can contact Jim Bradshaw at jimbradshaw4321@gmail.com or P.O. Box 1121, Washington LA 70589.