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The Universal Edibility Test

When I was a kid, it was my job to mow the lawn. There was a patch of weeds growing behind our garage. Calling those weeds a patch does not do them justice. They were more like a jungle. In my memory, there were hundreds of them, maybe even thousands; they were growing everywhere. Did I mention that I was only allowed to use a manual push-style lawn mower? My parents would not let me use the gas-powered mower because they worried I might chop my foot off. The unprotected spinning blades on the front of the push mower though, were perfectly safe. That thing was like a multi-bladed guillotine. The nightmare of trying to mow those weeds into submission is one which has returned often over the years. As I learned more about the edible and medicinal benefits of plants, I have spent a good bit of time wondering if those weeds might not have been some miraculous medicinal, or delicious edible, ripe for the picking.

Anyone facing a survival situation must make use of the resources they have. While plants surround us every day, very few of us know which of these plants will help us, and which ones might be harmful. This poses a unique question; short of carrying a botanist with us every day, how can the survivalist identify useful plants?

The answer to this question is the universal edibility test. We can use this tried and true test to determine if a plant is friend or foe. This test takes quite a bit of time and requires us to follow rigidly specific steps. Because of this, the universal edibility test is only feasible when you have a lot of the same plants growing nearby; much like that jungle in my back yard so many years ago.

To use this test, the survivalist must understand that different parts of a plant can be edible, while others may be toxic. To further complicate things, plant parts can be edible at one time in their growth cycle and toxic during others. This means a plant must be separated into each of its individual parts and said parts must be tested individually. It is also important to remember that some plants are only edible once they are cooked. You should therefore cook the plant part prior to starting the test.

The steps of the test are easy to remember if you memorize the acronym R.O.C.S.

  • Rub the plant on your inner arm
  • Oral input
  • Chew the plant
  • Swallow the plant

Rub: Crush the plant part and rub it on the inside of your wrist. If the plant is not good for your skin, it is definitely not good for the rest of your body. If you notice any itching, burning, redness, swelling, hives, or welts, etc., discard that plant part, wait 8 hours, and start the test again using the next plant part.

Oral: If there is no reaction, then place the plant part in your mouth, and hold it there for 15 minutes. Do not chew, the plant part. And definitely do not swallow it, or the saliva that will inevitably build up. If you feel any burning, itching, tingling, or numbness, immediately discard that plant part, wait 8 hours, and start the test again using the next plant part.

Chew: If you do not experience any adverse reactions, then it is time to chew the plant part. Be careful not to swallow it, or any of the juices. If you feel any burning, itching, tingling, or numbness, discard that plant part, wait 8 hours, and start the test again using the next plant part.

Swallow: If, however, there are not reactions, you can now swallow this part of the plant. You must not eat anything else, even things you know to be edible, for the next 8 hours. If after that time has elapsed, you have not experienced any adverse reactions, then it is safe for you to consumer this part of the plant. I would caution you to eat only a small amount at first, as you may still face gastric upset.

You may now repeat this test for each individual part of the plant. Be advised though, that there must be 8 hour fasts between each test. This fasting period gives your body time to adapt to what has already been eaten.