Rose comprises an outer fleshy layer, the hypanthium, which contains 5–160 "seeds" (technically dry single-seeded fruits called achenes) embedded in a matrix of fine, but stiff, hairs. Rose hips of some species, especially the dog rose ("Rosa canina") and rugosa rose ("Rosa rugosa"), are very rich in vitamin C, among the richest sources of any plant. The hips are eaten by fruit-eating birds such as thrushes and waxwings, which then disperse the seeds in their droppings. Some birds, particularly finches, also eat the seeds. While the sharp objects along a rose stem are commonly called "thorns", they are technically prickles—outgrowths of
National Fruit Collection in case one is lost. National Fruit Collection The United Kingdom's National Fruit Collection is one of the largest collections of fruit trees and plants in the world. Over 2,040 varieties of apple, 502 of pear, 350 of plum, 322 of cherry and smaller collections of bush fruits, nuts and grapes are grown, in of orchards. It has been curated and maintained at Brogdale Farm, Brogdale, Kent since 1952 and is owned by the Department for Environment, Food and Rural Affairs (Defra). The University of Reading took over day-to-day maintenance of the collection in 2008. The collection includes two trees