The reason they are using kløverFRØeng, rather than kløvereng, is that the meadow produces seed. This has two purposes, the first is that the seed has a market value (about 25000 metric tons of grass seeds are traded in Norway every year), but also to lock nitrogen in the depleted organic soil. There are limitations on what type of fertilizers that are permitted in organic soil, and growing grasses, such as clover and let them go to seed locks the nitrogen back in the soil.