nitrogen, making it valued on low fertility soils for the benefit it gives to other crop species in supplying nitrogen. It is also grazed by sheep and goats. The nitrogen fixing ability of Trifolium arvense depends on the size of nodule attach in the root system of legume. The sizes of nodule showing the positive correlation with the composition of community of microorganisms which are responsible for nitrogen fixing. In semi-arid area, the percentage of nitrogen originate from the atmosphere in total amount of nitrogen fixation done by Trifolium arvense has been maintained at a high level range which refers to 82%-91%. In raining season, the total quantity of nitrogen been fixed by Trifolium arvense is larger than the one in dry season. The medicinal value of Trifolium arvense has been discovered to treat both humans and animals. It has been introduced to North America, where it is an invasive species in some areas. Trifolium arvenseis also regarded as food by some animals like rabbit, wild turkey, deer etc. However, due to the hairy flowers of Trifolium arvense, if a horse or other livestock were fed with too much of them, abdominal obstruction may be caused leading to death. In addition, Trifolium arvense is also a kind of plant that has the characteristic of allergenicity. Although it is mild as allergen, it needs to be paid attention to. Scientists at AgResearch in New Zealand have used genetic modification to take a single gene from Trifolium arvense and put it into the more common white clover, Trifolium repens. The genetically modified clover could reduce bloating in livestock and decrease methane emissions. The release of the genetically modified clover is expected to be in approximately 2025. Management Being part of Fabaceae, Trifolium arvense is managed similarly to other weeds in the family. Trifolium arvense can be easily controlled in small scale field like home garden by hand-pulling, cultivation or using mulch. But when it comes to farm or landscape of wide field, due to the seeds of Trifolium arvense are highly tolerant of extreme temperature as well as physical damage because of their tiny size, long-term efforts of fighting against Trifolium arvense is required. Tillage and composting would not work well in this situation compared to other kinds of weeds. Chemical application is needed to assist to remove Trifolium arvense. Once the weedy situation is under control, changing the cultural practice and