Tree heather [wood = brier-root] (Eng), brezo blanco, brezo, berezo (Spa), bruc blanc, dinada (Cat), añar-zuria, zuricacha (Baq), urce, urce branca (Glg), urze branca, quiroga (Por).
“My practice has extended recently to the Continent,” said Holmes, after a while, filling up his old brier-root pipe.
‘Sherlock Holmes. The Sign of Four’, Arthur Conan Doyle
The tree heather is often a 2-4 m tall, very branching bush, taking on the forma of a tree in some places in the south of the Iberian Peninsula, such as the Alcornocales National Park. One of the reasons it remains smaller is because its root stock is highly valued and cut for various different uses. However, it can reach heights of up to 10 m in the Canary Islands, and 15-20 m in East Africa, on the slopes of Kilimanjaro. The young twigs are whitish and have uneven hairs. Its bark is brown and fibrous, and when mature it detaches in long thin strips. The leaves are hairless, persistent, simple, thin and very narrow. They are in the form of short needles, the edges of which curve over towards the underside in such a way that it appears to have a groove on the lower surface. They are 3-8 mm long, 0.5-0.7 mm wide, and are arranged on the twigs in whorls of 3 or 4, like the blades of a fan. The very small flowers are whitish, sometimes with a rosy tint, up to 3 mm in length, with a somewhat longer stalk, and they grow in pyramidal-shaped terminal groups. They are shaped like narrow, closed bells, and when mature the stamens remain inside, in contrast to other species of heather whose stamens poke out leaving the anthers (upper part of the stamen that contains pollen) on the outside.
This species is typical on acidic substrates and characteristic of humid forests or associated with the moisture provided by watercourses. It grows in the heart of beech, pine and oak forests, and forms extensive groups known as "brezales". It grows from sea level up to an altitude of 2000 m. In the Canary Islands and Africa it takes on the form of a tree and can exceed 10 m in height. It is surprising to see dense forests of this species, which on the Iberian Peninsula and in the Balearic Islands is normally a branching shrub. Centuries of using this species for wood has greatly limited the possibilities that it reaches tree-like statures in Europe.
The tree heather is a species found in diverse areas. It lives in the Mediterranean, the Canary Islands, Madeira, northern and eastern Africa, Asia Minor, and the Caucasus. It is common on the Iberian Peninsula and in the Balearic Islands but has an uneven distribution.