Ask Mr. Smarty Plants

The Lady Bird Johnson Wildflower Center, home of Mr. Smarty Plants, is committed to the growth, protection and propagation of plants native not only to North America but to the area in which those plants grow naturally; in your case, Prince William County, VA. Daylilies, once erroneously placed in the Liliaceae family of plants, now are considered to be in the Hemerocallis family. They are native to Eurasia - China, Japan and Korea - and are therefore out of our line of expertise. From the Univesity of Minnesota Extension Service, here is an article on Growing Daylilies. We understand there are many thousands of cultivars and selections of this plant, perennials which bloom one day, in the nursery trade, but beyond that, we know nothing about them.

However, we can talk about erosion; we don't know specifically which one you read but we have many previous answers on ways to control slopes. We saw a reference to the use of daylilies on a slope to control erosion because the roots reproduced, creating a network of roots which helped to hold soil on a slope, but we can't answer your question about landscaping cloth. Since we have no personal experience with it, we went looking for other information and found this funny article from North Coast Gardening Why I Hate Landscape Cloth. Here is a previous Mr. Smarty Plants answer on controlling erosion which includes further links to still other previous answers in various spots on the East Coast, including one from Virginia. We still prefer grasses with their long fibrous roots for erosion on a slope, but there are not many flowering plants that will have that sort of root.