The plant height can reach 1 m. The rhizome is long and horizontal, densely rusty yellow, and then gradually falls off. Ye Shengyuan; The stem is 20-80 cm long, the base is 3-6 mm thick, brown or brown straw color, slightly shiny and smooth, with 1 shallow longitudinal groove on it; Leaf blade is broadly triangular or rectangular-triangular, 30-60 cm long and 20-45 cm wide, with tapering top and rounded wedge-shaped base, with three pinnate compound leaves; 4-6 pairs of pinna, opposite or nearly opposite, obliquely spreading, the largest pair at the base (slightly smaller at the upper pair), triangular, long 15-25 cm, wide14-/8 cm, stalk about 3-5 cm long, and twice pinnate; The kohlrabi is about 10 pairs, alternate, obliquely spreading, lanceolate, 6- 10 cm long and 0/.5-2.5 cm wide. The tip of kohlrabi is tail-tapered (the base of the tail tip is slightly tapered), the base is nearly flat, and the stalk is short and pinnate. Lobes 10- 15 pairs, flat, close to each other, rectangular, about 14 mm long, about 5 mm wide, obtuse or nearly round-headed, the base is not United with Kohane axis, separate, entire; The pinnae above the middle part gradually becomes pinnate, oblong and lanceolate, with a wide and symmetrical base and a tail-shaped top. The pinna has the same lobes as the lower pinna, and some pinna have 1-3 pairs of shallow lobes or wavy teeth. The veins are dense and only visible below. After drying, the leaves are nearly leathery or leathery, dark green and hairless, and the lobes are slightly brown or grayish white and sparse or hairless below the main veins. Leaf axis and feather axis are smooth, the upper surface of feather axis is smooth, and the lower surface is sparse and dense (Populus tomentosa). Each feather shaft has a longitudinal groove 1 deep, and there is no hair in the groove. Chromosome 2n= 104.

It is produced all over the country, but it is mainly produced in the Yangtze River basin and the northern region, and it is also distributed in subtropical areas. Sunny places on sunny slopes of mountains and forest edges, 200-830 meters above sea level. It is also widely distributed in other tropical and temperate regions of the world. Type specimens were collected from Newfoundland and Saint Pierre, Canada.

The starch extracted from this rhizome is called edible fern powder, and the fiber of the rhizome can be used to make ropes and cables, which is waterproof and moisture-proof, and the tender leaves are edible, so it is called fern. The whole plant can be used as medicine to expel rheumatism, diuresis and reduce fever, and can also be used as insect repellent.

I was very happy when I learned that I also had ferns in Shandong! ! !