noun
Johnson grass; Egyptian millet
A perennial grass (Sorghum halepense) considered an invasive weed in many regions, but also used as forage. The Japanese name literally means 'Western barbarian sorghum'.
セイバンモロコシは繁殖力が強く、農地で問題になることがある。
Johnson grass is highly reproductive and can become a problem in farmland.
この地域ではセイバンモロコシが飼料として利用されている。
In this region, Johnson grass is used as fodder.
Refers to sorghum in general, while セイバンモロコシ specifically denotes Johnson grass (Sorghum halepense).
From 西蛮 (seiban, 'Western barbarian') + 蜀黍 (morokoshi, 'sorghum'). The kanji are ateji; the word is usually written in katakana.