Sea buckthorn is best known when its bright orange berries ripen in late summer. Sometimes, you can even smell a sour odor given off by the berries. Migrating birds are attracted to these berries, which are rich in vitamin C. The berries are ripe just in time for these birds and provide them with extra energy to fly further. Brown-tail moths use sea buckthorn as a food plant for their caterpillars. It's not unusual to find cocoons from these hairy insects built around one or more branches. Sea buckthorn grows in soils rich in calcium. In the Netherlands, that means relatively younger dunes. The plant needs lots of nitrogen to grow and has its own way of supplying its needs. In the process, it produces excess nitrogen, which helps various other dune plants and indirectly animals.