1, grey sky Han (drought) is also known as grey cabbage, wild grey cabbage, giant knotweed, etc. It mainly grows in fields, on the edge of the ground, beside the road, in front of and behind houses.

2. The main characteristics of Hedyotis cinerea: the young leaves at the seedling tips of Hedyotis cinerea have small white particles, and the tender tips of the seedlings are brighter in the daytime, which is the main difference from the tender seedlings of the toxic plant Datura stramonium. The tips of some seedlings of Han nationality in Tian Fei are purple.

3. Adverse reaction of eating Cynanchum otophyllum: Cynanchum otophyllum is non-toxic and edible, but Cynanchum otophyllum is a kind of wild vegetable rich in photosensitive substances. Exposure to the sun will lead to solar dermatitis after eating gray Tian Han or contacting the juice of gray Tian Han. If you eat too many gray vegetables at once or even for a week, edema will occur. 1958-1960 Many people ate it during the Great Leap Forward famine.

4. Edible medicinal value of Xu Changqing: sweet in nature, clearing away heat and promoting diuresis, lowering blood pressure, relieving pain, killing insects and stopping diarrhea; It can prevent anemia, promote children's growth and development, and has a certain health care effect on middle-aged and elderly people with calcium deficiency.