Sea buckthorn berries (Hippophae rhaminoides). This shrub can be invasive in sandy coastal areas. It is a pioneer species of nutrient-poor soil because it has the ability to fix atmospheric nitrogen and is useful in stabilising dune systems. However, it can become dominant and suppress other low growing plants. The increase in soil fertility in the soil surrounding its roots can lead to permanent changes in dune ecology. Photographed in Yellowcraig, East Lothian, Scotland, UK, in October.