Bull's ear grass is an umbel with two to five flowers, flowers large, calyx campanulate five-lobed; corolla two-lipped, light blue-purple, about one centimeter long, the upper lip two-lobed, the lower lip three-lobed; two stamens. Cow's ear grass leaves close to round, ovoid or ovate, less than seven centimeters long, leaf veins are not obvious, both sides have obvious white hairs, leaf edge with teeth or undulate lobed. Third, the difference between the use of pig's ear grass main use, one is the seedlings and young leaves can be used as vegetables to eat. Secondly, the whole grass and seeds can be used as medicine, with heat diuretic, expectorant, cool blood and so on. The whole grass of cow's ear grass can be used as medicine, which has the effect of treating otitis media and bruises.

"Pig's Ear" and "Cow's Ear" are not the official Chinese names of the plants, they are two families of plants, which are very different. I will briefly answer the question from two aspects, one is the difference of their position and origin in the plant classification system; the other is the difference of their plant morphology.

Pig's ear grass and cow's ear grass classification location and origin, pig's ear grass: the official Chinese name for the car before the plant, the plant family before the perennial herbaceous plants, the whole world * * * * production of about one hundred and ninety species, the Chinese production of twenty species, two of which for the invasive species, one for the cultivation and naturalization of the plant. Pig's ear grass origin is very wide, domestic except a few provinces do not produce, the rest of the places are produced. Cow's ear grass: the official Chinese name for the capsule chicory, Chicoryaceae capsule chicory perennial herbaceous plants, the world * * * production of about twenty species, China only produces three kinds. Cow's ear grass is mainly produced in Shaanxi, Liaoning, Central China, East China, South China, Southwest China, some of these provinces.

The pig's ear grass and cow's ear grass plant morphology, leaf blade difference: pig's ear grass rosette paper leaf blade base out, broadly ovate to broadly elliptic, four to twelve centimeters long, three to seven centimeters wide, leaf margin undulate or entire, petiole two to twenty centimeters; cow's ear grass rosette paper leaf blade base out, rounded or rounded-ovate, one to seven centimeters long, two to five centimeters wide, leaf blade villous. Leaf margins are dentate or undulate shallowly toothed, sessile.

Flower difference: hog's ear spikes dense or sparse, thin cylindrical, three to forty centimeters long, the corolla is white, June to July flowers; cow's ear grass cymes umbellate, with two to five, each inflorescence with two to five flowers, ten to eighteen centimeters long, corolla light blue-purple, July to August flowers. Fruit difference: pig's ear grass fruit is capsule type, ovate fusiform, ovoid or ovate conical, about half a centimeter long; pig's ear grass fruit is capsule type, oblong, about three to four centimeters long, about two millimeters in diameter.