Native Plants

Q. Who is Mr. Smarty Plants?
A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.
Did you know you can access the Native Plant Information Network with your web-enabled smartphone?
Ask Mr. Smarty Plants
Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

rate this answer

Tuesday - September 18, 2012
From: Sedalia, CO
Region: Rocky Mountain
Topic: Poisonous Plants
Title: Is it quantity that makes silver nightshade poisonous to people?
Answered by: Nan Hampton
QUESTION:
I have a recipe for Asadero cheese that uses silverleaf nightshade and have eaten this cheese many times. Is it too much quantity that makes it poisonous to people?ANSWER:
Solanum elaeagnifolium (Silverleaf nightshade), is called in our Native Plant Database "an aggressive, poisonous weed...". It isn't listed in Poisonous Plants of North Carolina (probably because silver nightshade isn't prevalent in the Eastern US), but the closely related Solanum carolinense (Carolina horse-nettle) is listed as Toxic Only If Large Quantities Eaten. Silver nightshade is listed in the Plants of Texas Rangelands as a toxic agent that:
"...has reportedly poisoned horses, sheep, goats, cattle and humans. However, sheep and goats are more resistant than cattle, and in controlled experiments, goats were not poisoned at all. Its toxic agent is solanine. The leaves and fruit are toxic at all stages of maturity; the highest concentration is in ripe fruits. In some instances, an animal can be poisoned by eating 0.1 to 0.3 percent of its weight in silverleaf nightshade."
The California Poison Control System gives all the Solanum species a Toxicity Rating of 1, meaning that the plants in the Genus Solanum "may cause serious illness or death".
The Veterinary Medicine Library of the University of Illinois lists all Solanum species and says that risk of poisoning depends on the species, the maturity of the plants and other conditions. They also say that for S. eleagnifolium it is the ripe berries that are more poisonous than the green unripe berries—this is in contrast to most other species of nightshade (and in contradiction of Plants of Texas Rangelands information). They also mention that silver nightshade can be poisonous at only 0.1% of the body weight.
Pennsylvania Poisonous Plants Database doesn't list S. eleagnifolium, but does list S. carolinense, S. nigurm [synonym=Solanum americanum (American black nightshade) and S. dulcamara (Bittersweet nightshade). S. tuberosum (potato) is also included for the potential of poisoning from potatoes with skins that have turned green due to sun exposure from growing too near the surface.
You can see my answer to a recent question about S. americanum (American black nightshade) and my advice about eating just one berry. I don't know what part of the silver nightshade you are thinking of using in making your cheese, but my advice to you is to read the information about the toxicity of all the Solanum species and use extreme caution before trying even a small amount of the plant. In fact, if I were you, I would avoid consuming even a small amount of it.
From the Image Gallery
More Poisonous Plants Questions
Identification of a cucumber-like vine with fruit
November 16, 2011 - We found tiny, grape-size white melon-like fruit on a vine, with tomato-like/cucumber-like seeds. The leaves on the vine were similar to grape or cucumber leaves, but not spiny. They were behind our...
view the full question and answer
Is the fruit of Bradford Pears toxic to dogs?
November 16, 2010 - I need to know if the little Berries on the Bradford Pear trees are toxic to dogs? My labrador loves eating them.
Thank you,
view the full question and answer
Plants toxic to dogs
December 08, 2005 - Can you tell me where I can get information on plants poisonious to dogs? Deck and yard plants. Thank you.
view the full question and answer
Getting rid of wild plums (Prunus angustifolia)
July 28, 2008 - When I bought my land, there was a humongous thicket of wild plums (Prunus angustifolia) approx 10 ft high and covering 5-10 acres. I raise goats, and have known that wild plums (the leaves) can cause...
view the full question and answer
Plant with dark black/purple berries in a cluster
November 06, 2012 - Today at our local dog park we noticed a bush/vine that's been growing up the fence is producing berries. It didn't flower at all. The berries look to have started out green and now are changing t...
view the full question and answer
Support the Wildflower Center by Donating Online or Becoming a Member today. |