Sweet White Clover

Sweet White Clover, Melilotus alba

Sweet White Clover was originally brought from Eurasia to North America as a forage crop, but it escaped cultivation and quickly spread across the continent. While it is most common in disturbed sites, it can also be found in high grade habitats. In addition, fire disturbances can result in explosive growth of sweet white clover, not only by creating good growing conditions, but by also scarifying and stimulating germination. It can efficiently degrade grassland communities by shading native species as it can grow up to 1.5 m (5 ft) tall. Each plant can produce up to 350,000 seeds which are viable for up to 81 years after storage, but it is unknown with environmental conditions, and of those in storage, only 0.6% were viable. While sweet white clover is visited by honeybees, native solitary bees, wasps, and flies, it can self-pollinate. The tap root may reach depths of 1.2 m (4 ft) within the first year and up to 1.7 m (5.5 ft) within the second year. Many species do consume sweet white clover including deer, elk, livestock,  cottontails, waterfowl, and song birds but grassland bird species richness in nonnative grasslands was lower than native grasslands. Prevention of spreading, establishment of perennial vegetation, herbicides within the first year, and frequent mowing are all methods of controlling sweet white clover with relative success.