Ecology and management of northern red oak (Quercus rubra L. syn. Q. borealis F. Michx.) in Europe: a review

Abstract

Northern red oak (Quercus rubra L. syn. Q. borealis F. Michx.) is a valuable broadleaved tree species originating from the eastern half of the USA and Canada. It was introduced to Europe in 1691 and currently covers over 350 000 ha, being found all over the continent, except the coldest part of Scandinavia. It is a fast-growing and valuable broadleaved tree due to its ecological characteristics, good wood properties and high economic value. Northern red oak prefers deep, loose, moderately humid and acid soils, without compact horizons and of at least moderate fertility. It does not grow well on dry, calcareous soils as well as waterlogged or poorly drained soils. It is either naturally regenerated using a group shelterwood system or planted using seedlings of European provenance, collected in certified seed stands. As northern red oak is light-demanding, its management should be ‘dynamic’ and includes heavy interventions (cleaning–respacing and thinning from above), in order to minimize crown competition between the final crop trees. These should produce large diameter trees for valuable end uses (e.g. veneer, solid furniture, lumber, etc.) within a rotation period generally of 80–100 years. The necessity for pruning (both formative and high) depends on the stand stocking at establishment, the subsequent silvicultural interventions as well as the occurrence of forking. The adaptation potential of northern red oak to predicted climate change, especially drought, seems to be higher than for European native oaks, the importance of the species is expected to increase in the future.

Biological Flora of the British Isles: Quercus rubra

“…(GBIF Secretariat, 2017; Lambdon et al, 2008; Nicolescu et al, 2018). In Europe the total area planted with Q. rubra for forestry covers c. 350,000 ha, mainly in Ukraine (193,000 ha), France (52,000 ha) and Germany (44,500 ha), while in other countries it covers <20,000 ha (Nicolescu et al, 2018). Q. rubra is also naturalized in the western United States (Colorado, Idaho, Oregon and Washington), Armenia and New Zealand (van Kleunen et al, 2019), and has been introduced in Argentina, Brazil, Chile, China, India, Japan, Kazakhstan and South Korea (GBIF Secretariat, 2017).…”

“…In its native range, Quercus rubra grows on a wide variety of soil types, from poor and dry sandy soils, through moderately moist loams to moist silty clay loams, with a pH range from 4.3 to 7.3 (Sander, 1990; USDA Forest Service, 2019; Wilson et al, 2018). Nevertheless, this species exhibits reduced growth rates on very dry or waterlogged soils (Nicolescu et al, 2018). Similar growth‐rate reductions occur on calcareous soils (Major, Nosko, Kuehne, Campbell, & Bauhus, 2013; Timbal & Aussenac, 1996).…”

“…Thinning intensity is usually intermediate, as maintaining canopies that are too dense, as well as increased exposure to light, leads to production of epicormic buds, which are silvicultural defects in the trunk that lead to depreciation in wood value. Target trees should reach 50–55 cm DBH to fulfil management expectations (Nicolescu et al, 2018). Q. rubra can be easily pruned without harm to the trees if small branches are cut (threshold is 3 cm diameter).…”

“…On the lowest productivity sites, only 15–20 m may be attained at 100 years. In Europe, Q. rubra stands can produce wood volumes of 2.7–14.6 m 3 ha −1 year −1 , depending on location and site conditions (Nicolescu et al, 2018). Dendrochronological studies revealed mean radial increments of 1.27 and 1.59 mm/year, according to two chronologies from western Poland (Cedro & Nowak, 2015).…”

“…Red Oak adult trees are also adapted to survive low temperatures, such as −40°C near St. Petersburg (Bellon et al, 1977; Nicolescu et al, 2018). Quercus rubra seedlings growing in the native range were not severely damaged by late‐spring frosts (Crow, 1992).…”