Posted by Eric Troy on 24 Feb 2013 01:29
Survival guides will generally give you some berry rules to live by. It goes something like this: Avoid white and yellow berries since about 90% of these are poisonous. About half of red berries are poisonous. Most black or blue berries are edible. Aggregate berries, like raspberry, blackberries, thimbleberries, and salmonberries, are 99% edible.1 These, unfortunately, on a bad day, could be rules to die by.
Given the above rules, you'd probably avoid any yellow or white berry. Therefore, you might miss out on some edible berries, like white mulberry. But that's better than getting poisoned. You'd also probably avoid all red berries. A fifty-fifty chance would dissuade most of us, even though some of the red berries are awesome. The problem is banking on the notion that most black or blue berries are edible.1
If you came upon one of the berries pictured below, you'd be forgiven for thinking it looked okay to eat, especially if you've never seen a blueberry bush. But the berries can make you sick, and if you really went to town on them, they could possibly be fatal. Funny thing is, they are in the grape family. These are the berries of Virginia Creeper or Parthenocissus quinquefolia.
Or could they be fatal? Do some research for yourself and see if you can get at the straight dope. You see, the berries contain some oxalic acid, but lots of the foods we eat do. Rhubarb does. It's not immediately poisonous unless it is present in a manufactured pure form and is ingested as a high dose. Some sources say, therefore, that the berries are not really so dangerous. But, if you look up Virginia Creeper you will immediately be told by most sources, some of which look very legit, that the berries are potentially fatal. Yet, no one seems to know what compound in the berries is the culprit and the supposed toxicity seems to be based on anecdotal reports and some berries given to guinea pigs.
Virginia Creeper with Blue Berries
Virginia Creeper with Blue Berries
Ironically, if you were a pretty good woodsman, you might think that the plant resembles something else that also sometimes has poison white berries; a plant you always avoid. Check out the leaves of the Virginia Creeper, below.
Leaves of the Virginia Creeper
Leaves of the Virginia Creeper
Remind you of anything? Virginia Creeper grows in much the same way as Poison Ivy, and the two are easily confused. Reportedly, Virginia Creeper leaves can also cause contact dermatitis, but not to the degree that Poison Ivy does. But let's say you are a big old expert, and you notice that while this Virginia Creeper plant has five-leave clusters, poison ivy has 3-leave clusters. Ah, it's not poison ivy and poison ivy has white berries, therefore, this plant with it's blue berries is probably good to go. And then you notice that a bird is happily snacking on the little blue morsels. While your watching, a mouse comes along, finds one below the plant on the ground, and starts nibbling away. Then a chipmunk gets in on the action, and, lo and behold, a skunk even joins in. Then, a deer comes along and starts eating not only the berries, but the leaves too! You're like Disney's Snow White as a smorgasbord.2
So, some berries killed a guinea pig but other animals are known to eat them. But they reportedly killed a child and according to many sources, are highly toxic to humans, because of unknown compounds, AND, because they contain enough oxalic acid to permanently damage the kidneys. You'd think that the information would not be so conflicting, in this modern age. But it an actually be quite difficult to absolutely pin down the safety of some berries, even with lots of research, and research is definitely better than a couple of rules-of-thumb. I wouldn't eat the berries of the Virginia Creeper, but I'm still not sure how dangerous the darn things are! According to the SAS Survival Handbook by John Wiseman, no plant with edible blue berries is vine-like with tendrils. Another rule of thumb!3
Poison Ivy Leaves
Poison Ivy Leaves
Okay, so the above scenario with all the animal friends would be highly irregular, but the point is that you do not want to assume because birds or animals eat a berry, it's okay. Many animals seem to be immune to poison ivy and sheep, goats, and cattle have been observed eating the leaves and berries with no ill effect.4 And a variety of sources indicate that anywhere from 55 to 75 species of birds regularly eat the berries.
If you were in a survival situation, though, the rule of thumb could be your first step. Well, your first step would probably be to consult a more qualified source than this blog, but you catch my drift. The berry rules could help guide you to berries that you could then test for edibility using a field test. In this case, you would completely avoid all white and yellow berries, and go very cautiously with red berries. While you would go ahead and test most black or blue berries.
To test a berry, you'd use the same procedure that you would use for plants. Since I am going to provide the procedures (for grins) I need to add some warnings, lest the unwary apply it unprepared. Here are some general rules to start:
1. Don't apply this to mushrooms.
Unless you can positively, 100% identify a mushroom as edible, don't eat it. The Universal Edibility Test does not work for mushrooms. The poisons in a mushroom, which are usually protein based, may not cause any immediate reaction, but then you cash it in a few days later (I'm kidding, a little. See link below).
Most all survival guides say that you should never eat mushrooms in a survival situation unless you really know what you are doing, and mushroom identification is a very difficult science to master. There is a lot of information on gathering wild mushrooms for your own enjoyment, and though it seems like a fun thing, I wouldn't do it. You may actually be able to gather edible ones successfully, but easily mix in a poison one. It is often said that some species can mean certain death.
There are NO TESTS for the edibility of mushrooms, besides eating them and seeing what happens. Don't believe any crap you read about self tests, because they are false. There is one myth that says if you rub a clove of garlic or a silver coin on a mushroom and the mushroom does not turn black, it is safe. There are other general rules for identifying edible mushrooms by certain characteristics, which are listed in various guides, but I wouldn't touch them if my life depended on it (get it?).
That being said, I am perhaps being a bit paranoid. The fear of "certain death" upon eating a poisonous mushroom is a common one, but it is not necessarily a legitimate one. See Myths About Mushroom Poisoning.
2. The Universal Edibility Test, sometimes called the Field Edibility Test is nowhere near full-proof.
If you've been watching too many survival shows and you think it is a substitute for learning to positively identify edible plants, then you need to think more and watch less. You can go without food for quite a long time, so don't go picking plants and testing them the next time you get lost in a walk through the fields.
Taste, by the way, is not an absolute indicator of whether a plant is edible. Just because it tastes good, does not mean it will not kill you. Avoid plants with:
- Milky or discolored sap, especially that which turns black when exposed to air
- Beans, bulbs, or seeds inside pods (basically avoid anything that looks like a bean or pea, unless you grew it in your garden).
- Flower bulbs. Many flower bulbs are toxic.
- Bitter or soapy taste
- shiny leaves
- Spines, fine hairs, or thorns
- Umbrella-shaped flower clusters (looking like Queen Anne's Lace or dill)
- Foliage that resembles dill, carrot, parsnip, or parsley
- An almond scent in the woody parts or the leaves (this signals cyanide)
- Grain heads with pink, purplish, or black spurs
- Three-leaved growth pattern
- Signs of disease like fungal infection. If it looks like it's sick, don't bother with it
Some plants with the above characteristics are edible. Or, rather, the leaves might be edible, but not the stems. For instance, dandelion greens are absolutely edible, but the stems exude a milky sap. If you know a dandelion when you see it, and what kid doesn't, you can eat the leaves and they are very nourishing. But don't let that cause you to not take the milky sap rule seriously. Some white berries are edible as well: I think you get the point.
3. All parts of the plant must be tested separately. Test only one part of a plant at a time.
It is very common for one part of a plant to be edible but other parts poisonous. Maybe only the roots are poisonous. We actually eat plant things that grow on poisonous plants. Tomatoes, potatoes, and eggplants, to name a few.
4. Only test ONE plant at a time.
This should make perfect sense if you think about it a second. You could easily lose track of things if you tried testing more than one plant at a time, with very bad results.
5. A plant can be edible cooked but not edible raw.
Some toxic compounds can be neutralized by cooking, especially in boiling water. If you test a cooked plant and find it edible, and you even eat it for a while with no problems, you'd still have to test it raw to see if it is edible raw.
6. Don't eat for 8 hours prior to starting the test.
You need to have processed any food you consumed and start with a clean slate.
7. Don't eat anything else while testing a plant.
This could interfere with the test. Drink only water (that has been purified).
8. You are probably only reading this for curiosity and you will never be in a situation to need it.
The Universal Edibility Test is only for EXTREME situations in which if you don't use it, survival is not likely. It's a last-ditch response.
Universal Edibility Test
1. Separate the plant into its basic components: leaves, stems, roots, buds, and flowers.
2. Smell the plant for strong acidic or other odors. If present, select another plant.
3. Prepare the plant in the way you plan to eat it, raw, baked over a fire, boiled, etc.
4. Place a piece of the plant on the inside of your wrist or elbow for fifteen minutes to check for contact dermatitis or other reaction. Wait for burning, stinging, itching, or irritation of any kind. If any of these happen, stop the test and throw away the plant. Select a new plant and start over.
5. If no reaction occurs during the skin test, hold a small amount of the plant to your lip and wait for five minutes. If any burning, or other irritation occurs, as above, discontinue.
6. If no reaction occurs during the lip test, place a small portion of the plant on your tongue, and hold it there for fifteen minutes. I don't know why the lip test is shorter. Ask an expert. Monitor for any reactions, as above. If any occur, start over with a new plant.
7. If your tongue doesn't shrivel up and fall off, or nothing else of note occurs, take a small amount of the plant and chew it thouroughly, then hold it in your mouth for 15 minutes. DO NOT SWALLOW THE PLANT or the JUICE.
8. If no burning, itching, numbness, stinging, or any other irritation occurs during the mouth test, go ahead and swallow the cheowed plant. Wait for 8 hours. If you experience any kind of reaction, like cramps, nausea, vomiting, or other gastrointestinal upset, induce vomiting and drink lots and lots of water.
9. In nothing occurs after 8 hours, eat about 1/4 cup of the same plant part prepared the exact same way and wait another 8 hours. If nothing happens during this test, you can consider the plant safe to eat. Make sure to test any other parts of the plant separately.
10. Although the plant is deemed edible by the test, you'd be better off to still eat it in small amounts, separated by some time period because it is still possible that large amounts could cause you to be sick and have vomiting and diarrhea. Even if it is not downright poisonous, being sick in that way is just going to void any of the nutrients from you body and dehydrate you. 5,6
Remember, I got this information from books, such as the U.S Army Survival Guide, the U.S Air Force Survival Guide, and other sources. I cross-checked many sources for accuracy. Most of them just repeat what is in the various Army guides, and the military devised the test in the first place. However, there is a lot of missing information here that a true expert would be aware of. I wrote this to satisfy my own curiosity as much as anything else. I did not write about this because I know anything about survival. I wrote about it because I am a better than average researcher, know more than average about food science, I know how to separate good sources from bad, and recognize BS when I see it.
While writing this, I even came across some survival websites that got some things obviously wrong. For instance, one site seemed to think that the edibility test would work for mushrooms, but that the danger was in mistaking your tested and edible mushroom for a poisonous one, because they can look so alike. So, just because the word survival is in the name of a site or a book, does not mean it is a credible source. I would not present this as information that would help you survive, but only information that would satisfy your curiosity and leads you in the right direction. That probably makes this as good a starting point as any for the information presented, but far from a survival guide or any other kind of guide.
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