sour dock, yellow dock, narrow-leaved dock
Curly dock is a long taprooted simple (non-branching) perennial that grows in a rosette. The 6-8" long elliptical or lance-shaped leaves of curly dock have entire but wavy margins (not toothed). The youngest leaves smooth margins that get progressively more rippled as the leaf matures. The appearance of the mature leaves resembles leaf lettuce (very curly).
Curly dock is often a weed of low maintenance areas. In the absence of mowing, curly dock will produce several tall flower stalks in late summer. The flowers form greenish clusters at the top of the stem that turn brown as they ripen. The foliage can be covered with purple/brown spots that range from a few to covering the entire leaf as the nighttime temperatures drop toward the end of the growing season.
Curly dock frequents roadside ditchbanks and other low-maintenance areas and will thrive in nutrient-rich, damp soils.