Human overpopulation and the increasingly exacerbating climate change have led to eminent food crisis. To heighten awareness of cherishing foods, Chunghwa Post is issuing a set of four stamps each featuring a type of gramineous plants, including Oryza sativa, Setaria italica, Zea mays, and Triticum aestivum. The designs follow:1. Oryza sativa (NT$5): Commonly known as rice, it is an annual, herbaceous plant. The rice has long, slender leaves, with parallel veins, and covered with minute hairs. The flowers are arranged in panicles. When mature, the fruit is golden yellow in color, and the seed, milky white. Rice prefers warm and rainy weather. In Taiwan, rice is grown primarily in Changhua, Yunlin and Chiayi Counties. It is also a staple food for the people of Taiwan. 2. Setaria italica (NT$7): Commonly known as millet, it is an annual, herbaceous plant. Lanceolate or linear-lanceolate in shape, the tip of the blade is pointy and slender, and the base is roundish. The flowers are arranged in a spike panicle. The fruits are either oval- or globose-shaped. Millet is a crop suitable for warm season areas at the low altitude. In Taiwan, the crop is chiefly cultivated in the eastern part of the country and a common staple food for the aborigines. 3. Zea mays (NT$10): Commonly known as maize, it is an annual, herbaceous plant. Monoecious, maize is bred through cross-pollination. The male flower grows at the apex of the stem, while the female flower grows half way down the stem. The fruits are either yellow or white in color. Maize prefers farmlands or hillsides, where temperature is high and sunlight is sparse. In Taiwan, maize is planted primarily in Hsinchu, Miaoli and Jianan Plain. It is a food crop, also a vital source of fodder. 4. Triticum aestivum (NT$25): Commonly known as wheat. Depending on the growing season, there are two types of wheat: the annual spring wheat, or the winter wheat. The leaf is linearis, and the flowers are arranged in spike. The fruits are either oval- or ovate-shaped. In Taiwan, wheat is grown predominantly in Tanzi, Daya, and Xitun Districts in Taichung City, plus Xiushui and Fuxing Townships in Changhua County. Wheat is milled for a variety of flours; it is also a material for brewing wine, and making soy sauce and vinegar.