By Tulla Lightfoot
Slender Yellow Wood Sorrel April 12, 2022
The beautiful Slender Yellow Wood Sorrel is a perennial that began to blossom in April, growing in clumps alongside the edge of the Greenway path where there was a lot of sun. I also saw the plant growing profusely alongside roadways in patches of sunlight as well as in the parking lot of my local supermarket. At first, I thought the plants were buttercups, but on closer inspection, I noticed that they had heart shaped leaves that strongly resemble Clover. The scientific name for the plant is Oxalis dilleniid. The leaves of plants in the Oxalis genus may look similar to Clover but they are in an entirely different family. The Slender Yellow Wood Sorrel is native to America while the only Clover native to North America is Trifolium ciliolatum, or the Foothill Clover. This plant originated in California, but can now be found growing anywhere from Washington state, south to Baja California. It definitely does not grow on my east coast Greenway. Foothill Clover does not seem to be a particularly useful plant either because it can cause bloating or might even poison anyone who tries to eat it.
Most Clover plants we see are either a type of White Clover, Trifolium repens L, or the now less common, Red Clover, Trifolium pretense. These plants originated in Europe and Central Asia and were brought to North America by the European colonists as food and medicine for themselves and as forage for their animals. European colonists loved these plants and bought them along where ever they roamed so that they are now found growing all over the world.
Slender Yellow Wood Sorrel grows from seeds but also from bulbous roots which multiply and divide like daffodils and tulips. Clover also grows from seeds, but in addition, can root from above-ground runners called stolons. As food for livestock, White Clover is extremely successful because even if its leaves and flowers are eaten, the runners quickly recover with timely regrowth increasing forage yield for grazing animals that have eaten everything else. White clover is also important as a cool season animal food because it grows in late winter to early spring before the warm season perennials appear or have low nutritive value. Clover has been found to be a beneficial plant because it has a symbiotic relationship with Rhizobium bacteria that infects the plant’s roots. The clover plant provides food for the bacteria, while the bacteria converts atmospheric nitrogen into a form that the plant can use. The nitrogen is held in the plant’s root nodules and is slowly released as the roots decompose. Nitrogen is also released in the urine and dung of the animals eating the clover becoming valuable fertilizers for grasses. Adding nitrogen to the soil reduces the amount of nitrogen fertilizer farmers need to use, which makes the plant economically beneficial.
Red and White Clover have been studied for their medicinal properties since the time of ancient Greece. Modern testing has found that Red Clover contains isoflavones which can treat menopausal conditions, such as hot flashes. It has also been used to treat cancer, whooping cough, respiratory problems and skin inflammations such as psoriasis and eczema. All parts of the White Clover plant above the ground are edible for humans. I find that raw Clover tastes a little like spinach but with a weird after-taste, but some people think the dried leaves of the plant taste like vanilla and use them in baked goods. For the adventurous, Clover leaves can be used in salads, soups or stir-fries as long as you’re certain the plants have not been sprayed with herbicides. Fresh Clover flowers can garnish various dishes. Dried, Clover flowers add flavor to jelly, baked goods and cool beverages. White Clover contains vitamins A, B2, B3, C and E as well as magnesium, potassium, and other minerals. The leaves can also be used as an antiseptic eyewash for minor eye infections and made into a poultice for external wounds and sores. However, the plant can have a blood thinning effect and might interfere with medications for hypertension.
While native to America, Slender Yellow Wood Sorrel is also now found in Europe, perhaps brought there for its beauty and its taste as the Europeans traveled back and forth. The leaves, flowers and unripe fruit are all edible. The plant tastes sour and tart, with a yummy lemony flavor. These parts of the plant can be added to salads, soups and sauces, or used as seasoning. Steeping leaves in boiling water for 5 to 10 minutes makes a good tea and seed pods can be ground into a spice to add flavor to a dish. Unfortunately, the plant contains high levels of oxalic acid. And while humans and animals need some oxalic acid, an excessive amount of it will damage the kidneys. Too much must also be avoided for those who have rheumatoid arthritis or gout. Despite the oxalic acid, the plant has been used topically to cool skin, and internally to soothe stomach aches. It can also be useful in treating scurvy, fever, urinary tract infections, sore throats, nausea and mouth sores. The flowers can be used to make an orange-yellow dye.
The Slender Yellow Wood Sorrel grows to 15 inches tall. The stems are usually erect and the leaves are arranged alternately on the stem and are divided into 3 heart shaped leaflets which fold in the evening or when it’s cloudy. There are from 1 to 5 yellow blossoms on a slender stem and the flowers are ½ to 1 inch across with 5 sepals, 5 petals, 10 stamens and 1 pistil. The seed pods grow upwards on their stalks and have five compartments with about ten seeds in each. I haven’t witnessed this, but when the pods are ripe, they’re supposed to explode at the slightest touch, launching the seeds as far as ten feet from the mother plant. This plant is tolerant of a wide variety of conditions, but is usually considered a weed and ripped out, poisoned or mowed as soon as lawn grasses start to come in.
So when you see these plant enjoy them for the brief time in the spring that they are dominant. They are easily culled by lawn mowers and don’t recover as readily as Clover plants do. Their new growth is low to the ground, small and easily over looked. They also seem to get overwhelmed by the taller grassy plants that spring up as time goes by, and they are easily poisoned by herbicides that at the same time, feed one’s lawns. Slender Yellow Wood Sorrel are early bloomers, and for a brief time in early spring, they are beautiful patches of golden yellow decorating our paths and roads.
To learn more about Clover or Slender Yellow Wood Sorrel, check out these references below:
Mount Sinai, Home Health Library, “Red Clover” https://www.mountsinai.org/health-library/herb/red-clover#:~:text=Red%20clover%20is%20a%20wild,such%20as%20psoriasis%20and%20eczema.
The Planet, “White Clover, a Sweet and Nutritious Edible Weed”, May 2019 updated April 2022, https://eattheplanet.org/white-clover-a-sweet-and-nutritious-edible-weed/#:~:text=A%20white%20clover%20infusion%20can,aches%20and%20joint%20pain%20too.
Dr. Joe bouton, Southeast AgriSeeds, “Everything You Wanted to Know About White Clover (But Were Afraid to Ask an Old University Professor!”, https://southeastagriseeds.com/blog-posts/everything-you-wanted-know-about-white-clover-were-afraid-ask-old-university-professor#:~:text=White%20clover%20was%20introduced%20into,simultaneously%20with%20the%20early%20settlers.
The University of Texas at Austin, Plant database, at https://www.wildflower.org/plants/result.php?id_plant=oxdi2 retrieved 4/13/22
Bonnie L. Grant, Gardening, “Is Yellow Woodsorrel Edible: Taking Advantage of Yellow Woodsorrel Uses” at https://www.gardeningknowhow.com/plant-problems/weeds/yellow-woodsorrel-uses.htm#:~:text=As%20a%20medicinal%2C%20woodsorrel%20has,can%20help%20in%20cancer%20cases. Retrieved 4/13/22
Healthline, “Sorrel: Nutrients, Benefits, Downsides, and Recipes” https://www.healthline.com/nutrition/sorrel-benefits
University of Wisconsin-Madison, Wisconsin Horticulture “Common Yellow Woodsorrel, Oxalis stricta” https://hort.extension.wisc.edu/articles/common-yellow-woodsorrel-oxalis-stricta/