Poisonous Berries: Impostors or a Mystery?

[Adeimantus]

Are there what might be called 'impostor' berries that look similar to tasty, edible berries but are actually poisonous? A few days ago I happened up on a berry that looked almost exactly like a blackberry, but it was growing on a small woody tree-like plant that had 3-lobed leaves and no thorns. I was tempted to eat it, but decided instead to smash it and smell it. It didn't smell appetizing. If it was in fact poisonous, it makes me wonder why the plant would go to all the trouble to make an attractive fruit that isn't nutritious to animals (like me) that might otherwise eat it and spread the seeds.

 

[Evo]

It sounds like it may have been a small Mulberry tree. I grew up with them. They are edible.

http://en.wikipedia.org/wiki/Mulberry

Also

Mulberries are extremely juicy and have a refreshing, subacid, saccharine taste, but they are devoid of the fine aroma that distinguishes many fruits of the order Rosaceae.

Which could explain why you were put off by the smell, especially if you were expecting it to smell like a blackberry.

http://www.botanical.com/botanical/mgmh/m/mulcom62.html

An example of something that looks like an edible berry (tomato) but is in fact poisonous, is the nightshade plant (bella donna). The fruits look like little green tomatoes and are actually related to tomatoes, which is why hundreds of years ago, people where afraid to eat tomatoes.

http://www.pharmacy.arizona.edu/outreach/poison/plants/silverleafa.jpg

http://simple.wikipedia.org/wiki/Nightshade

 

[Adeimantus]

Thank you! The description of the mulberry plant at Wikipedia seems to match what I saw. The article says that the sap is a hallucinogen. Perhaps a scientific investigation is in order. Also, it says mulberry is known as Toot in the middle east. My guess is they named it after eating too many on an empty stomach

In the case of the nightshade, I wonder if it is poisonous to all critters or just some of us. Why would a plant make a tempting poisonous fruit? Sooner or later animals will learn to spot the deception and then the seeds won't be spread in the customary fasion. Right?

 

[Evo]

In the case of the nightshade, I wonder if it is poisonous to all critters or just some of us. Why would a plant make a tempting poisonous fruit? Sooner or later animals will learn to spot the deception and then the seeds won't be spread in the customary fasion. Right?

Nightshade spreads through rhizomes as well as seed. It's almost impossible to kill off.

 

[jim mcnamara]

Before you go off the deep end consider that a lot of foods we eat contain small amounts of plant toxins. Consider rhubarb - consuming the leaves will make you ill, but the petiole (the celery-like part) is edible - at least in the sense that it doesn't kill you... The list goes on and on:
http://www.geo-pie.cornell.edu/issues/toxins.html

This is very likely why humans over time selectively grew plants with lower levels of plant toxins. The wild cousins of domesticated plants often have higher levels of these toxins - which the plant uses as a defense against herbivory. Domesticated plants are practically defenseless in some cases.

 

[Moonbear]

In the case of the nightshade, I wonder if it is poisonous to all critters or just some of us. Why would a plant make a tempting poisonous fruit? Sooner or later animals will learn to spot the deception and then the seeds won't be spread in the customary fasion. Right?

Without citing specific examples, not all plants have the same strategy for spreading seeds. While some may need to run through the digestive tract of an animal to prepare the seed coat for germination, others may be harmed by that and simply need to drop to the ground or be carried by the wind where they are. And, you would be correct that not all plants that are poisonous to humans are poisonous to other species. Things we cannot eat, birds perhaps can eat...a little further dispersal than we'd accomplish with walking.

 

[Adeimantus]

. Consider rhubarb - consuming the leaves will make you ill, but the petiole (the celery-like part) is edible - at least in the sense that it doesn't kill you... .

haha. I haven't had rhubarb but I've never heard anything positive about it. Thank you for that helpful link. It makes sense that plants would have a whole arsenal of chemical weapons to keep things like cows, goats, insects, fungi, etc. from munching on them. I understand that caffeine and cocaine are examples of such chemical weapons, although they give humans a pleasant buzz if taken moderately. I was not aware that the concentration of toxins could vary so much depending on the environmental stress the plant is under. That's interesting.

What I'm concerned about is the possibility of some super-toxic berry that kills you after eating two or three. That seems like overkill to me, from a self-defense perspective. I doubted that such plants existed, but then I found this semi-reliable looking web page that lists all sorts of common plants that are supposedly very dangerous:

http://plantanswers.tamu.edu/publications/poison/poison.html

However, this other equally reliable looking page, from Children's Hospital of Philadelphia, lists some of the same plants as hardly toxic in small quantities, so I don't know who is telling the truth:

http://www.chop.edu/consumer/jsp/division/generic.jsp?id=70991

Without citing specific examples, not all plants have the same strategy for spreading seeds. While some may need to run through the digestive tract of an animal to prepare the seed coat for germination, others may be harmed by that and simply need to drop to the ground or be carried by the wind where they are.

That's a good point. thank you.

 

[jim mcnamara]

The tamu site is Texas A&M's link to their Botany Department. chop.edu is the Children's Hospital.

The folks at tamu are reporting the lab findings and concentrations found in lab extractions.
chop is reporting clinical observations. The two are valid science.

Most toxic higher plants when eaten do things like:
1. burn your mouth and throat - oxalates in "dumb cane' - Dieffenbachia spp. are an example.
2. taste really awful - Rhododendron leaves

Clinical reports often find that kids only eat a portion of a foul-tasting leaf, then parents go beserk, the kid gets sick and the clinicians have to deal with it.

The reasons why the two reports vary are several things. Foods already in the stomach bind with nasty 'anti-nutrients' reducing their effect. Gastric enzymes may alter part of the toxin molecule rendering it less nasty. Kids are not going to chow down on some that tastes god-awful, so the total amount of toxin is less than it might otherwise be. On the other hand, the lab person isolates the stuff and goes through a lot of steps to extract the toxin. Your body does the opposite with a lot of toxins.

However, severe and fatal poisonings are still reported from toxic higher plant ingestion, but they are not common.

But. IMO For deadly: The winner is Basidomycetes - 'mushrooms and toadstools' . For example, George Washington Hosptial in Washington DC had a doc on staff in the 50's and 60's who really knew mushroom-ology. The reason was that DC has thousands of European Embassy people. People from Europe go 'shroom gathering. The nasty species over here look like the tasty table species in Central Europe. Voila - embassy staff presenting at GW violently ill the day after a picnic in Rock Creek Park. He kept photos of the usual suspects (like Amonita) on the wall so he could get an idea of what the patients had eaten. I used to bring in specimens for his 'herbarium' when I was doing other field work.

The embassies now train staff NOT to eat wild mushrooms but rather, buy their mushrooms at the International Safeway downtown - if it is still there.

Bottom line - don't eat the plants listed on either site.

 

[Moonbear]

Kids are not going to chow down on some that tastes god-awful, so the total amount of toxin is less than it might otherwise be.
...

However, severe and fatal poisonings are still reported from toxic higher plant ingestion, but they are not common.

I suspect that other than kids being dared by other kids to eat something nasty tasting, or cases where safe foods get mixed in with unsafe ones disguising the taste of the bad one, the other likely place for someone to ingest lethal doses of a poisonous plant would be in a survival situation with someone whose common sense or survival skills are weak. Someone may reason that they need food and should ignore the foul taste of the berry to get some nutrition into them, not realizing the foul taste is a warning not to ingest that food.

Afterall, as the OP already noticed, those inedible berries gave him sufficient warning they were inedible before he even got one to his mouth, simply by smelling strange.

 

[JonMoulton]

I suppose if death came swiftly enough after ingestion, a plant could self-fertilize with the carcasses of unwary animals that consumed toxic fruit -- but only if death came before the animal could leave the root zone. I doubt there is a plant toxin that acts so swiftly when eaten. However, given the large region occupied by a mature mycelium, perhaps a fungus could derive some nutrition from unwary mushroom-eating victims.

 

[Adeimantus]

The tamu site is Texas A&M's link to their Botany Department. chop.edu is the Children's Hospital.

The folks at tamu are reporting the lab findings and concentrations found in lab extractions.
chop is reporting clinical observations. The two are valid science.

Most toxic higher plants when eaten do things like:
1. burn your mouth and throat - oxalates in "dumb cane' - Dieffenbachia spp. are an example.
2. taste really awful - Rhododendron leaves

Clinical reports often find that kids only eat a portion of a foul-tasting leaf, then parents go beserk, the kid gets sick and the clinicians have to deal with it.

The reasons why the two reports vary are several things. Foods already in the stomach bind with nasty 'anti-nutrients' reducing their effect. Gastric enzymes may alter part of the toxin molecule rendering it less nasty. Kids are not going to chow down on some that tastes god-awful, so the total amount of toxin is less than it might otherwise be. On the other hand, the lab person isolates the stuff and goes through a lot of steps to extract the toxin. Your body does the opposite with a lot of toxins.

...

Bottom line - don't eat the plants listed on either site.

OK, that makes sense now. And I guess I will stick with store-bought mushrooms!

 

[epenguin]

Moral, don't eat your greens!

Seriously, there is something in this, summary of some research was published under title 'Evolution and diet' in The Economist Sep 21st 2006 but I cannot supply link.

I think there are cases of plants that mimic the appearance of poisonous plants and so benefit from the avoidance. I have heard of insects that do that, they tend to hatch a bit later than the ones they mimic as the avoidance is a learned behaviour by birds. I have seen on an authoritative source (TV Nature features ) that some birds and, I think mammals (elephants) consume minerals that detoxify otherwise toxic foods. Sorry for the thirdhand sources.

 

[jim mcnamara]

MB -

I had a tenure in the USDA - in the Seed Lab. We used to get stomach contents for id, especially when the items had seeds in them. Rosary beads were a problem, for example. Anyway, the number fatalities attributed to plant materials versus the number of reported cases was very small. My sample from Washington DC metro hospitals was about 40 years ago.

 

[Ouabache]

It sounds like it may have been a small Mulberry tree. I grew up with them. They are edible.

http://en.wikipedia.org/wiki/Mulberry

Also Which could explain why you were put off by the smell, especially if you were expecting it to smell like a blackberry.

http://www.botanical.com/botanical/mgmh/m/mulcom62.html

I was bicycling through a little town in Indiana called Mullberry (pop'n < 1400), and all along the roadside leading to town, you might guess what I found. Mullberry trees, and they were loaded with berries , what a treat for a weary traveller.. Their leaves are polymorphic, with the trilobe shape, the OP described, as one of these variations.

An example of something that looks like an edible berry (tomato) but is in fact poisonous, is the nightshade plant (bella donna). The fruits look like little green tomatoes and are actually related to tomatoes, which is why hundreds of years ago, people where afraid to eat tomatoes.

http://www.pharmacy.arizona.edu/outreach/poison/plants/silverleafa.jpg

http://simple.wikipedia.org/wiki/Nightshade

Good analogy! While tomatoes were embraced in the cuisine of Spain, Italy & France, for sometime, people further north (British Isles), viewed them as ornamentals in their flower gardens, for their pretty red berries. I suspect their varieties looked like cherry tomatoes. They were aware, tomato belonged to the deadly nightshade family and believed they were poisonous. They brought this thinking with them, as they populated the American colonies and even until mid-1800s, tomatoes were regarded more as an ornamental than a vegetable ref01

Be careful not to eat potatoes that have been stored in sunlight and tissue turned green. They are also nightshades and the green tissue indicates a higher concentration of the glycoalkaloid - solanine. It can make you feel ill. http://www.ianrpubs.unl.edu/epublic/pages/publicationD.jsp?publicationId=208

 

[Ouabache]

It sounds like it may have been a small Mulberry tree. I grew up with them. They are edible.

http://en.wikipedia.org/wiki/Mulberry

Also Which could explain why you were put off by the smell, especially if you were expecting it to smell like a blackberry.

http://www.botanical.com/botanical/mgmh/m/mulcom62.html

I was bicycling through a little town in Indiana called Mullberry (pop'n < 1400), and all along the roadside leading to town, you might guess what I found. Mullberry trees, and they were loaded with berries , what a treat for a weary traveller.. Their leaves are polymorphic, with the trilobe shape, the OP described, as one of these variations.

An example of something that looks like an edible berry (tomato) but is in fact poisonous, is the nightshade plant (bella donna). The fruits look like little green tomatoes and are actually related to tomatoes, which is why hundreds of years ago, people where afraid to eat tomatoes.

http://www.pharmacy.arizona.edu/outreach/poison/plants/silverleafa.jpg

http://simple.wikipedia.org/wiki/Nightshade

Good analogy! While tomatoes were embraced in the cuisine of Spain, Italy & France, for sometime, people further north (British Isles), viewed them as ornamentals in their flower gardens, for their pretty red berries. I suspect their varieties looked like cherry tomatoes. They were aware, tomato belonged to the deadly nightshade family and believed they were poisonous. They brought this thinking with them, as they populated the American colonies and even until mid-1800s, tomatoes were regarded more as an ornamental than a vegetable ref01

One a similar note, take care not to eat potatoes that have turned green from exposure to sunlight. They are also nightshades and the green tissue indicates a higher concentration of the glycoalkaloid - solanine. It can make you feel ill. http://www.ianrpubs.unl.edu/epublic/pages/publicationD.jsp?publicationId=208

 

[Ouabache]

It sounds like it may have been a small Mulberry tree. I grew up with them. They are edible.

I was bicycling through a little town in Indiana called Mullberry (pop'n < 1400), and all along the roadside leading to town, you might guess what I found. Mullberry trees, and they were loaded with berries , what a treat for a weary traveller.. Their leaves are polymorphic, with the trilobe shape, the OP described, as one of these variations.

An example of something that looks like an edible berry (tomato) but is in fact poisonous, is the nightshade plant (bella donna). The fruits look like little green tomatoes and are actually related to tomatoes, which is why hundreds of years ago, people where afraid to eat tomatoes.

Good analogy! While tomatoes were embraced in the cuisine of Spain, Italy & France, for sometime, people further north (British Isles), viewed them as ornamentals in their flower gardens, for their pretty red berries. I suspect their varieties looked like cherry tomatoes. They were aware, tomato belonged to the deadly nightshade family and believed they were poisonous. They brought this thinking with them, as they populated the American colonies and even until mid-1800s, tomatoes were regarded more as an ornamental than a vegetable ref01

One a similar note, take care not to eat potatoes that have turned green from exposure to sunlight. They are also nightshades and the green tissue indicates a higher concentration of the glycoalkaloid - solanine. It can make you feel ill. http://www.ianrpubs.unl.edu/epublic/pages/publicationD.jsp?publicationId=208