Pinus nigra aka Austrian Pine

Austrian pine, Pinus nigra, is an evergreen conifer in the pine family, Pinaceae. Gardeners also know it as black pine, Corsican pine, Calabrian pine and larch pine. Its wild range is scattered across southern and central Europe and the Mediterranean. It also reaches northwest Africa, Asia Minor and the northern Caucasus. The name nigra means black and refers to the dark bark.

In gardens this tree usually reaches 40 to 70 feet (12 to 21 metres) tall. It spreads 20 to 40 feet (6 to 12 metres) wide. Old trees can reach about 100 feet (30 metres). Young trees are dense and pyramidal. With age the crown opens out and becomes flat-topped or umbrella-shaped, with stout spreading branches. The trunk is short and straight.

The bark is dark grey-brown to nearly black. On mature trees it breaks into thick plates split by deep furrows. The needles grow in pairs and measure about 3 to 6 inches (8 to 15 cm) long. They are stiff, sharp-tipped and dark green with a bluish cast. Bent back, they do not snap easily, which helps separate this tree from red pine. Each needle stays on the tree for three to eight years. Young stems are greenish-brown and turn scaly and grey with age.

Small yellow pollen cones cluster at the base of new shoots in spring. Small purplish seed cones form at the shoot tips. The woody seed cones are oval and pale to yellowish brown. They grow 2 to 3 inches (5 to 8 cm) long and ripen in autumn. They often sit in groups of two to four and point outward from the stem. Wind carries the pollen.

This pine needs full sun and good drainage. It prefers moist ground but adapts to clay, loam, sand and chalk. It accepts acid, neutral or alkaline soil. Once settled it tolerates drought, salt, wind, heat and city pollution. It suits USDA zones 4 to 7 and earns the RHS rating H7. It needs no pruning and moves well when transplanted. Gardeners use it as a specimen, screen or windbreak, and along coasts and roads. As old trees open up, they screen less well. Deer tend to leave it alone. Imperial moth caterpillars feed on the foliage.

Disease is the main drawback. Sphaeropsis (Diplodia) tip blight kills shoot tips and has made the tree a poor choice in parts of the American Midwest. Dothistroma needle blight, other needle casts and honey fungus can also strike. Pests include adelgids, aphids, sawfly larvae and scale insects. Pine shoot moths, needle miners, spittlebugs, spider mites and pine wilt nematode may also appear. The tree has little food value, though pulpwood resins yield a vanillin flavouring. Turpentine from pine resin has a history in folk medicine. The wood, sawdust and resin can irritate the skin of sensitive people. The needles give a tan or green dye.