Yellow Trillium © 2014 Patty Hankins
What can I saw about yellow trillium – other than I know I’m in the Smokey Mountains in the spring when I start seeing yellow trillium (trillium luteum).
Yellow Trillium (trillium luteum) are one of the most easily identifiable spring wildflowers that bloom in the Smoky Mountains – once your realize what it is! I’d seen several varieties of the white, pink and red trilliums before I saw the yellow ones – and at first I didn’t recognize them as trillium. All the ones I’d seen before then had been pedicillate trilliums where the petals seem to open out from a central point. Yellow Trillium are sessile trilliums, where the petals seem to grow straight up from the stem.
Native to the Southeastern United States, Michigan and Ontario, Canada, yellow trillium bloom in the spring. They can grow to about 16 inches tall. The three mottled green leaves grow to 6 inches long. The three yellow petals start out as a green yellow aging to a deeper yellow. They grow basicly erect from the stem.
If you are in the right place, you can see big clusters of yellow trillium. And if you go back the next year, chances are – the patch of yellow trillium will be even bigger. 
Yellow Trillium is one of the wildflowers featured in my 2015 Wildflower Calendar. You can order your copy from my website.