After a long week in Texas, it was nice to spend a restful afternoon at our family prairie last Saturday. The weather was gorgeous and we spent a great day playing with the dogs, cooking hot dogs on a campfire, cutting small cedars, hiking, and (of course) doing a little photography.
When diffuse clouds covered the midday sun for a little while, I grabbed my camera and set out to add some photos to a little project I’ve been working on – finding color in winter prairies. The subjects that caught my eye on Saturday were prairie plant rosettes. Most biennial plants (and some short-lived perennials) in our prairies spend their first year as a tightly arranged cluster of leaves close to the ground – a rosette. Those leaves photosynthesize enough to get the plant’s root system started, giving it a head start on its second year growth. Often, rosettes are found in areas of prairie that are recently grazed or mowed because competing plants are both short and weak, opening up space for new plants to establish. Rosettes often stay green much of the winter, but the leaves can also turn other colors like red or yellow.
As I write this, I realize that I don’t actually know for sure how rosette leaves work. I’ve always assumed that the leaves on a rosette lose their green color for a while during the coldest parts of winter and then green up again in the spring. That is different from what most prairie forbs (wildflowers) do, of course, because their leaves drop off in the fall and they grow new ones in the spring. Does anyone know if leaves in a rosette really can turn red/yellow and then green again?