A fossilized tree trunk protrudes through ice near Antarctica's Mount Achernar.
Norbert Nagel, Wikimedia Commons
Medical marijuana gets all the headlines, but many legal weeds have traditions as medicines too. Although homeowners often consider these plants as lawn outlaws, weeds can serve as a floral pharmacy. However, would-be patients of the plants should consult a doctor before self-medicating.
Cichorium intybus, the light blue flower frequently seen along roads, provides the main commercial source of the compound inulin. Patients take inulin to fight high blood fats, including cholesterol and triglycerides, according to WebMD. Research published in Diabetes & Metabolism Journal suggests that inulin intake benefits women with type-2 diabetes by reducing the rate of blood sugar increase after eating. Inulin promotes the growth of certain bacteria in the intestines. While some believe this can help digestion, others suffer serious flatulence when the inulin-fed bacteria build up.
Some people add the dried and roasted root to coffee. Chickory coffee is especially popular in New Orleans.
Böhringer Friedrich, Wikimedia Commons
Trifolium pratense contains chemicals known as isoflavones. These chemicals can act like the female hormone estrogen in the body. Doctors have examined the clover chemicals as a treatment for hot flashes and other symptoms of menopause. However, doctors warn that women with a history or risk of breast cancer should avoid isoflavones, since estrogen-like chemicals have been associated with increased incidence of some cancers.
H. Zell, Wikimedia Commons
Silybum marianum has a 2,000 year history as a liver medicine. Modern research has looked at thistle extracts as a treatment for alcohol-induced liver damage. Substances in milk thistle, particularly the chemical silymarin, may protect the liver from damage after a person takes an overdose of other medications, including acetaminophen (Tylenol). Milk thistle may also be an antidote to poison from the deathcap mushroom (Amanita phalloides). Animal studies found that milk thistle completely counteracted the poison if given within 10 minutes of poisoning, according to the University of Maryland Medical Center.
Muffet, Wikimedia Commons
Native Americans used the milkweed (Asclepias sp.) as a contraceptive, according to the U.S. Department of Agriculture. The milky, white sap that gives the plant its name served to remove warts. However, milkweeds also contain chemicals known as cardiac glycosides. These chemicals can cause severe illness in humans and livestock. Monarch butterfly caterpillars eat milkweed and build up high concentrations of glycosides, which makes the insects nasty tasting to predators.
Tony Hisgett, Wikimedia Commons
Ancient Greeks and Romans used horsetail (Equisetum arvense) to stop bleeding, heal ulcers and wounds, and treat tuberculosis and kidney problems. My wife drinks horsetail tea to flush out her body’s system and help lose weight. The tea has a mildly bitter flavor, similar to chamomile. Research published in Ethnopharmacolgy found that horsetail tea increases urination which corroborates my wife’s contention that the plant is a diuretic, or a substance that increases urination. However, doctors recommend taking a multivitamin when drinking significant amounts of horesetail tea, because it can flush nutrients, such as vitamin B1, thiamin and potassium, out of one's system as well.
J. Carmichael, Wikimedia Commons
In the past, Europeans used remedies made from dandelion (Taraxacum sp.) roots, leaves and flowers to treat fever, boils, eye problems, diabetes, and diarrhea, according to the University of Maryland Medical Center. Practitioners of traditional Chinese medicine take dandelions for stomach ailments and breast problems, such as inflammation or lack of milk flow. Dandelion leaves taste similar to spinach and contains vitamins A, B, C, and D, along with iron, potassium, and zinc.
Uwe H. Friese, Wikimedia Commons
Urtica dioica can put the hurt on an hiker in shorts, but historically the plant has served to treat aching muscles and joints, eczema, arthritis and gout. People still use the plant to treat joint pain, and some studies have suggested that the plant can treat arthritis. Another study found that capsules of dried stinging nettle may reduce the symptoms of hay fever. Europeans frequently use stinging nettle root to treat bladder problems. Boiled nettle makes a side dish similar to collared greens.
For those who brush alongside stinging nettle, a remedy to the sting is often found growing nearby. Applying crushed up dandelion, horsetail, Aloe vera, jewelweed or the leaf of a dock or lock plant can counter the acid in the sting.
Forest and Kim Starr, Wikimedia Commons
Like many of the medicinal weeds in this list, purslane (Portulaca oleracea) also makes a healthy snack. The plant contains a high content of omega-3 fatty acids. I ate some that grew in my yard and found it was somewhat sour. A little bit was good, but too much would be overpowering in a salad. In traditional Chinese medicine, purslane treats genito-urinary tract infections. Research published in Phytomedicine found that the plant reduced problems with cognition in older mice.
Robert Steers/NPS, Wikimedia Commons
Since the age of the ancient Greek doctors have used plantains (Plantago sp., the weed in sidewalk cracks, not the fruit) to speed wound healing. In the training manual Survival, Evasion and Recovery, the U.S. Department of Defense recommends plantain as a poultice on wounds or as a nutrient-rich tea to treat diarrhea.
Julia Adamson, photographer in the Saskatoon area, Wikimedia Commons
Traditionally, healers use burdock (Arctium sp.) to clear toxins from the blood and increase urination, according to the University of Maryland Medical Center. The plant also is used to treat skin ailments, such as eczema, acne, and psoriasis. The leaves and roots of burdock are edible and contains inulin, like chicory, so they may aid digestion and/or cause a nasty case of flatulence. Burdock also contains high quantities of antioxidants that can prevent damage to cells.
Strange forests with some features of today's tropical trees once grew in Antarctica, new research finds.
Some 250 million years ago, during the late Permian and early Triassic, the world was a greenhouse, much hotter than it is today. Forests carpeted a non-icy Antarctic. But Antarctica was still at a high latitude, meaning that just as today, the land is bathed in round-the-clock darkness during winter and 24/7 light in the summer.
The question, said Patricia Ryberg, a postdoctoral researcher at the University of Kansas Biodiversity Institute, is how plants coped with photosynthesizing constantly for part of the year and then not at all when the winter sun set.
"The trees are the best way to figure this out, because trees record physiological responses" in their rings, Ryberg told LiveScience.
A forest mystery
Fossilized wood and leaf impressions record a history of the Antarctic forests. The leaf impressions appear to show mats of leaves, as if the trees had all shed at once — a sign of a deciduous forest.
To confirm this, Ryberg and her colleagues gathered samples of fossil wood and examined the tree rings. Wood cells in the rings reveal how the trees grew: Early wood is produced when the tree is growing upward and outward. Late wood is produced when the tree is preparing to go dormant. At that point, the tree stops growing and starts storing carbon in its cells. Late wood is denser than early wood, and has thicker cell walls.
Deciduous and evergreen trees have different patterns of late and early wood. Ryberg and her colleagues examined the Antarctic fossils and found that they looked evergreen. [Image Gallery: Life at the South Pole]
"Now we have leaves that suggest a deciduous habit and fossil wood that is suggesting an evergreen habit, so we have a bit of a contradiction going on," Ryberg said here Wednesday (Oct. 30) at the annual meeting of the Geological Society of America.
Follow-up studies analyzing carbon molecules in the fossil wood also gives both deciduous and evergreen answers, Ryberg said. The implication is that ancient Antarctic forests may have been a mix of deciduous and evergreen.
"It's not one or the other," she said. "It's actually both."
Much of the ring structure looks tropical, Ryberg added. Tropical trees that are not exposed to seasons experience a sort of short-term dormancy that echoes what is seen in the Antarctic wood.
"But they weren't growing in the tropics, so obviously it's two different environmental characteristics," Ryberg said.
Ryberg is now investigating how much plant matter these strange Antarctic forests produced. It's not yet clear whether the forests grew more densely than those seen in modern forests.
Follow Stephanie Pappas on Twitter and Google+. Follow OurAmazingPlanet @OAPlanet, Facebook and Google+. Original article at LiveScience's OurAmazingPlanet.
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