Of 250 species belonging to genus Trifolium, only two namely T. repens and T. pratense are important forage crops in the temperate areas. Both these species are perennial and self incompatible. T. repens (white clover) has longer productive life and its dry matter yield varies behvcen 8-13t/ha. in Netherlands and 2.0–15.5t/ha. in UK, while T.pratense (red clover) has shorter productive life of 1.5 to 3 years and its production is 6–10 t/ha. The study revealed that T. pratense is more efficient than T. repens so far as RE2 is concerned but in case of RE3T. repens is more efficient and it invests more in female track. This confirms that T. pratense is obligate outbreeder while T. repens has a tendency towards inbreeding.