This is a tall lanky plant that sways back and forth in the wind and is difficult to photograph. Yellow Sweet Clover is quite similar to Melilotus alba (White Sweet Clover), which is another weedy species that has been introduced from Eurasia for agricultural purposes. This latter species has white flowers, greyish green foliage, and its slightly reticulated seedpods lack conspicuous transverse ridges. Otherwise, these two species are nearly identical. As a matter of fact, some authorities regard Yellow Sweet Clover and White Sweet Clover as different varieties of the same species. In my experience, Yellow Sweet Clover begins to bloom about 2-3 weeks earlier than White Sweet Clover, and it is more often found at sites that are moist and fertile.