also translated from Chinese, only some portions of the article:
Yichang Orange
Distributed in China's Shaanxi, southern Gansu provinces, western Hubei, western and northwestern Hunan, northwest Guangxi, Guizhou, Sichuan, and Yunnan. The highest limit of natural distribution is about 2500 meters in the mountains. There are also cultivated ones. Born in high mountain cliffs, rocks, ridges or slopes along river valleys.
The fruit is oblate, round or pear-shaped, light yellow, rough, oily cells are large, obviously convex, the flesh is pale yellow and white, very sour, with both bitter and tingling taste.
Flowering from May to June, fruiting from October to November.
This species is distributed along the banks of the rivers north of central Guizhou. It has the shortest leaves and small flowers; distributed in the northwest of Guangxi, its leaves are the largest, with wings of 10-15 cm long and large fruit, about 6 cm in diameter. The shape of its young fruit is similar to that of young Limeng or Citron, broad oval, slightly narrow and pointed at both ends, and smooth skin; distributed in Yangbi and Baoshan in western Yunnan, its wings and leaves are usually slightly longer than the leaves. And wide, the leaf texture is thin, the leaf edge has more obvious fine crack teeth, and the peel is also very thin.
From the morphological diversity of each organ of Yichang orange and its variation range, that is, the shape and size of leaves, flowers and fruits, the color of flowers, single embryo and single-multi-embryo mixed type.
Yichang orange has a wide natural distribution area and strong adaptability, so there are different types. Field and cultivation observations show that there are at least two types of purple flower type and white flower type.
The petals of the white flower type are white, but the part near the calyx is lavender red. It blooms first and then taps. The wings and leaves are small. The seeds are mixed with multiple single embryos.
The petals of the purple flower type are bright lavender red, wider, and taper when blooming, and the wings and leaves are longer than the leaves. The fruit is nearly oblate, and its calyx is enlarged and thickened; the calyx of the pear-shaped fruit is usually flat, but also thickened and raised, and its leaf body and leaves are very large. These types of fruits usually do not fall through the winter, so fruits of different ages exist on the same tree at the same time, commonly known as Gongsun Tang.
Yichang orange is one of the excellent rootstocks for grafting citrus plants, and can dwarf the plant.
https://baike.baidu.com/item/%E5%AE%9C%E6%98%8C%E6%A9%99/5129531?fr=aladdinYichang orange is used as a citrus rootstock, which is resistant to cold and barren. According to reports, using Yichang orange as the rootstock of Pioneer Orange has a dwarfed crown and good fruit quality, but the root system is poor.
Since 1982, our institute has carried out a comparative experiment of different interstocks for Wenzhou mandarin oranges. ...the length of the interstock is 20 cm...
After more than 10 years of observation and records, it is found that Yichang orange is ideal as an interstock. Its main performance: strong rootstock affinity, growth is strong but not vigorous.
Yichang Orange is widely distributed from the north of Wuling to about 34°N latitude.
http://www.360doc.com/content/13/0814/09/1630322_307015856.shtmlWuling would be the Nanling Mountains.
"barren" probably refers to leaf drop.
Also keep in mind that China experiences colder winter temperatures at the same latitudes than the US does.