The plants of the mountain regions are mostly evergreen, whether they are tiny plants, or grow as mats or cushions, shrubs or stunted forest trees. This is true even of those which are covered in snow for half the year. One of the first impressions, during the flowering season, is of the profusion of flowers, and at the same time of the lack of colour. The flowers are nearly all white, and many of the leaves appear grey due to the thick covering of hairs. Even those plants which are found in other parts of the world with coloured flowers, in the New Zealand mountain areas have white flowers. Gentians elsewhere are known for their bright blue colours, but the 24 species here are white, or very faintly streaked with colour. Our forget-me-nots are pale or deep yellow, though in sub-Antarctic Islands the forget-me-nots are blue as are the gentians. In fact, blue flowers are very rare in New Zealand; the little orchid Thelymitra is blue but Wahlenbergia gracilis, the blue-bell, is usually a dingy white. A number of flowers are yellow such as Helichrysum coralloides and several species of Senecio which include some of our most beautiful shrubs. S. lautus is the most common, S. bellidioides is abundant in sub-alpine regions, S. lyallii with white or yellow flowers is common in alpine passes, while S. scorzonerioides, the snow groundsel, one of the most showy New Zealand plants, is found on wet herb fields. Some Hebes have tiny pale mauve flowers, and Cotula atrata, found on shingle slips, has flowers which are almost black. In contrast to the lack of colour in flowers are shrubs with brightly coloured berries (Coprosma, Myrsine, Gaultheria).