Wanted to start this topic a while back and am just now getting around to it. With all the interest in flint and bone artifacts, not much thought is given to the plants that the natives used, for food or medicinal purposes. Being as I'm down here in the So.Tx. brush and spend most of my time out there, I see all sorts of edible plants and seeds and have gained a lot of knowledge from the old timers on things that could be eaten to survive. So I did a little research and though some of the plants mentioned below didn't say they were used by the natives, I'm sure they were. Who could pass up the chance on eating something good when you're hungry.
So here's part 1 of this subject.
Agarita: Used to treat toothaches/The wood and roots were used to create a yellow die
Anaca***ta/Mexican Olive: Fruit is edible/Used to make cough medicine
Bald Cyprus: Resin from the cones is used as analgesic for wounds
Black Persimmon: Fruit is edible/black dye can be made from the fruit
Black Sumac: Black dye can be made from the fruit
Candalabrum/Cholla: Fuit can be made into a dye
Candy Cactus/Devils Pincushion: Edible berries
Catclaw Acacia: Native Americans made a mush out of the seeds and used it for back pain
Cenizo/Texas Silverleaf /Purplesage: Native Americans used it for fever and chills
Confite Blanca/Velvet Lantana: Edible berries
Encino/Tx. Live Oak: Bark used to make tannin, used for curing hides
Flame Acanthus: Indians used parts of the plant to treat colic
Guayacan/Soap bush: Hardest wood in the country/bark of the root has an ingredient for making soap/root extracts used to treat rheumatism
Honey Mesquite: Native Americans used the seeds for bread and alcohol/A black dye or a cement for pottery can be made from mesquite and the gum from bark was eaten as candy or dissolved in water for dysentery, wound or scratchy throat treatment/The seeds can be toxic in large quantities
Horse Bean/Retama: Food and medicinal uses include: flour from seeds and a diabetes and fever regimen through tea.
Jaboncillo/Western Soapberry: The seed have been used as a medicine to treat renal disorders and fevers and is commonly used in Mexico as a laundry detergent due to it’s lathering ability. They are inedible containing a poisonous substance called saponin
Kidneywood: The wood has been used for dyes and is flourescent in water.
Mustang Grapes: Edible if skin is removed from seed
Nopal/Texas *****ly Pear: Fruit is edible and its joints when tender make a peppery dressing
Palma Pita/Spanish Dagger: Leaves used for rope and thatch/the blossoms were used for pickles or cooked like cabbage. It is also said that Indians made an intoxicating beverage by fermenting the fruit. I have tried the flowers made into cakes, not bad tasting at all
Willow: Native Americans across the American continent relied on it as a staple of their medical treatments. This is because willows contain salicin, a substance that chemically resembles aspirin. Salicin is metabolized in to salicylic acid in the human body, which is a precursor of aspirin.
Texas Agrilife Research & Extension Center @ Uvalde
There was a whole bunch more listed that I didn't include. You have to go through pages of Texas plants to find those listed that have been proven to be used by the natives and even then some were regional. Used in one area and not another even though abundant. There's still more data being accumulated on usage. Didn't find much on coastal plants yet though.