Yellowroot is rare in the nursery trade but this small shrub is native across eastern North America and featured at renowned arboreta such as Arnold in Massachusetts and JC Raulston in North Carolina.

I was searching for a garden candidate beginning with the letter X recently, (yes, I know that's not usually how a garden is planned, but that's another article) when I came across Xanthorhiza simplicissima, yellowroot. Yellowroot is a small woody plant native to a large part of eastern North America, but it is rare in cultivation and hard to find in gardening books. The Arnold Arboretum in Boston and the JC Raulston Arboretum in Raleigh include this plant in their andscapes. Yellowroot's native status, early spring bloom and fall color made me want to create a complete "X file" on the plant.

Photo: details of early spring flowers on yellowroot

Yellowroot grows in sun or shade in zones 3 to 9. Its natural range covers a wide swath from Maine to Louisiana. In the wild, yellowroot prefers moist locations and streamsides. It is a woody deciduous plant forming a thicket of suckering stems starting about a foot tall and increasing in height each year, to three feet. William Cullina, in Native Trees, Shrubs, and VInes, says yellowroot can be kept under three feet tall by pruning after a decade or so. Unique starry purple flowers emerge from these stems in early spring before leaves come out. The foliage is a bright glossy green, lacey and divided. When autumn arrives, the yellowroot is at its showiest. The leaves turn yellow, then bright rosy red, fading to tan and persisting into winter. The plant is easy to propagate from cuttings and diviisions, according to Cullina. The small seeds are eaten by a variety of wildlife.Yellowroot was used medicinally by native Americans.

Let's just call it yellowroot.

Xanthorhiza simplicissima is quite a mouthful. When you break down those Latin words, the name isn't as intimidating. Xanth means yellow, a reference to a pigment that makes the wood and the roots (rhiza) yellow. Simplicissima refers to the simple, unbranched (uncomplicated) stems. Yellowroot makes for a great Latin mini-tutorial. Interestingly, this is the only species in this genus, and the only woody species in the Ranunculus (buttercup) family.

I don't know that I've ever seen yellowroot in a natural setting. It should be growing somewhere within my stomping grounds of central Maryland woodlands. The maps at USDA PLANTS for this species show it as found somewhere in MD but no county data is given. Possibly yellowroot is not as happy in my coastal plain soil as it is in more landlocked forests. I could really find it much more easily if I could see it "in person," but where?

The US National Arboretum is my biggest, best and closest place for unique plant observation. Happily, yellowroot appears in Annotated List of Plants Growing Naturally at The National Arboretum created by Oliver M. Freeman in 1953. More digital digging turned up a helpful tool on the U. S. National Arboretum website. The Arboretum Botanical Explorer search and mapping tool showed me that I can find yellowroot in their Fern Valley native plant collection. Unfortunately, as I write this, the ground is snowcovered and the windchill in the negative range, so I won't be visiting the Arboretum before this is published. THere isn't much to see until early spring when the flowers open. You can be sure I'll plan a visit in early May when I should be abe to see some flowers and early leaves.

And yellowroot IS available at nurseries. Just don't look for it in the run-of-the-mill mail order catalogs and big box garden centers. FInd this plant at specialty growers like these:

Sunshine Farm and Gardens

American Beauties Native Plants (see their tool for finding local vendors)

Lazy S'S Farm Nursery

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Credit and resources

thumbnail photo by TheAlphaWolf "Yellowroot- Xanthorhiza simplicissima.". Licensed under CC BY-SA 3.0 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:Yellowroot-_Xanthorhiza_simplicissima..JPG#mediaviewer/File:Yellowroot-_Xanthorhiza_simplicissima..JPG

See more images:

Lady Bird Johnson Wildflower Center site, wildflower.org, http://www.wildflower.org/plants/result.php?id_plant=XASI

North Carolina Native Plant Society site, ncwoldflower.org, http://www.ncwildflower.org/plant_galleries/details/xanthorhiza-simplicissima/