Quercus palustris

Pin oak (Quercus palustris)

The pin oak (Quercus palustris), also Spree Oak, Oak Boulevard or nail - oak (English: " pin oak " ) called, is a species of the genus of oak trees in the beech family ( Fagaceae ). It is often used in moderate latitudes as an ornamental plant in parks and avenues.

• 5.1 Notes and references

Description

Appearance, bark and leaves

The swamp - oak grows as a deciduous tree reaching at good locations at the age of 30 years, plant height of about 20 meters and trunk diameter ( diameter at breast height DBH ) of an average of 28 centimeters. Old specimens can reach heights of growth of up to 37 meters and trunk diameter ( DBH ) of up to 1.5 meters or more in exceptional cases. They develop crowns 8-20 meters in diameter. Swamp oaks are usually rapid, but form a relatively short-lived species that are usually only reached an age of 80 to 100 years. Single copies may be 150 to 200 years old. The roots of the swamp - oak form a flat heart root system.

The oak species for relatively thin bark is pink inside and outside grayish - brown with broad furrows. The bark of the branches is reddish - brown and is bald early. The brown to reddish - brown terminal buds are egg-shaped with a length of 3 to 5 mm; they are bald or have at the top a few fine hairs.

The alternate and spirally arranged on the branches leaves are divided into petiole and leaf blade. The bald petiole is 20 to 60 mm long. The simple elliptical has a length of 5 to 16 cm and a width of 5 to 12 cm to elongate lamina five to seven lobes and the edge of the sheet has from 10 to 30 points. On both surfaces of leaves glabrous, except for a few groups of woolly hairs on the prominent main nerves of the lower leaf surface. In the autumn the leaves turn reddish to scarlet and are therefore very decorative.

Generative features

The flowering time is in spring simultaneously with the foliation. The pin oak is monoecious getrenntgeschlechtig ( monoecious ). At previous year's branches hang the male, kitten -shaped buds in the leaf axils. At this year's shoots are in the leaf axils on a short shaft, the female flowers. The female flowers have dark red scars. Pollination is accomplished by the wind.

The one with a height of 3 to 6 mm and a diameter of 9.5 mm to 16 mm shallow cup-shaped fruit cup ( cupula ) externally bald hairy until fluffy and envelops the glans only a quarter full. The over the winter on the tree consistent, bald acorn ( nut fruit ) is egg-shaped with a length of 1 to 1.6 cm and a diameter of 0.9 to 1.5 cm spherical to; it is often striped significantly. The distribution of acorns is from September to early December in the following year for fertilization.

The chromosome number is 2n = 24

Dissemination

The pin oak is native to eastern North America. Its natural range extends from southwestern New England States westward to the extreme southern Ontario, southern Michigan, northern Illinois and Iowa, and south to Missouri, eastern Kansas and northeastern Oklahoma, then east to the central Arkansas, Tennessee, central North Carolina and Virginia.

The locations of areas of river valleys of the submontane level are possible, which can be flooded over several weeks. Wetlands, however - unlike the name suggests - shunned. The Pin Oak grows well in normal and moderately dry sites.

System

The first publication of the species name Quercus palustris was in 1770 by Otto Freiherr von Munchhausen in The householder, 5 (1 ), pp. 253

Quercus palustris forms natural hybrids: Quercus × mutabilis Palmer & Steyerm. ( Quercus shumardii ) × vaga Palmer & Steyerm. ( Quercus velutina with ), Quercus × schochiana Dieck ( Quercus phellos ), Quercus x columnaris Laughlin ( Quercus rubra) and an unnamed hybrids with Quercus coccinea.

" Renaming the Spree - oak "

The mid-1990s decided the Berlin Senate and the then Chancellor Helmut Kohl, to plant a few hundred trees in Berlin's new government district. It was decided to use the oak species Quercus palustris. The first copy of these trees was planted on 27 March 2000 in the Paul Loebe Avenue (near the Reichstag ).

However, since it was feared the fact that the seat of government of swamp oaks surrounded could lead to unpleasant puns, one designated for this type of hand. The nearby Spree borrowed the trees the new name " Spree- oak ". Various sources contradict each other but in the question of who had caused this naming: The Berlin Senate Administration, Helmut Kohl or the planters of the first tree, Thierse ( President of the Bundestag in 2000), while the latter, the first variant confirmed.

Meanwhile, taking on more and more nurseries and garden called " Spree- oak ".

Swell

• Kevin C. Nixon: Quercus in the Flora of North America, Volume 3, 1997: Quercus palustris - Online. (Section Description, distribution and systematics)
• Robert A. McQuilkin: Quercus palustris in Silvics Manual, Volume 2: Hardwoods at USDA Forest Service Northeastern Area. (Section Description, distribution and hybrids)