Technical guidelines for genetic conservation and use Turkey oak Quercus cerris Quercus cerris Quercus cerris Q Marco Cosimo Simeone1, Peter Zhelev Stojanov2 and Gaye Kandemir3 1 University of Tuscia, Viterbo, Italy 2 University of Forestry, Sofia, Bulgaria 3 Forest Tree Seeds and Tree Breeding Research Institute Directorate, Ankara, Turkey These Technical Guidelines are intended to assist those who cherish the valuable Turkey oak gene pool and its inheritance, through conserving valuable seed sources or use in practical forestry. The focus is on conserving the genetic diversity of the species at the European scale. The recommendations provided in this module should be regarded as a commonly agreed basis to be complemented and further developed in local, national or regional conditions. The Guidelines are based on the available knowledge of the species and on widely accepted methods for the conservation of forest genetic resources. Biology and ecology Turkey oak (Quercus cer- ris L.) is native to Europe and Asia Minor and exhibits strong morphological variability and ecological adaptability. It has deciduous leaves and ovoid acorns with big curly cups, which ripen in the second year (Sep- tember–October). It may reach 30–35 m in height, with a straight trunk up to 2 m in diameter and 5–5.5 m in circumference. The crown is oval, broad and open. The bark is thick, rough and deeply furrowed into irregular horizontal and vertical ridges. The inner part is characteristically red. Leaves are yellow-green, with 6–12 triangular narrow lobes and deep incisions on each side. The regularity of the lobbing varies greatly, with some trees having very regular, moderately to deeply incised lobes TurkeyQuercus oakQuercus cerrisTurkey oakQuercus cerris Turkeycerris oakQuercus cerrisTurkey QuercusoakQuercus cerrisTurkey oakQuercus cerrisTurkey cerris oakQuercus cerrisTurkey oak QuercusQuercus cerrisTurkey oakQuercus cerrisTurkey oakcerrisQuercus cerrisTurkey oakQuercus Quer cerrisTurkey oakQuercus cerri (var. Haliphleos and Cerris), Distribution Importance and use while others are just toothed (var. austriaca). Leaves are shed in October. Turkey oak is a very impor- Due to its relatively fast growth, Turkey oak is characterized tant forest species in south- Turkey oak is widely planted and it by mesophilous-subcontinental central and eastern Europe and is naturalized in much of Europe. behaviour. It is wa- Anatolia; it occurs as far south It is used as ornamental in parks ter-demanding and as the mountains of south and gardens, and as windbreak. moderately resist- Lebanon/northern Israel. Its The timber has no valuable tech- ant to low and high distribution is centred round nological properties; it is prone to thermal extremes. Un- the lower parts of the Danube cracking and splitting and hence der xeric conditions, its Basin, in Croatia, Hunga- commonly used for fencing, fuel competitive ability de- ry and around the Black wood and charcoal, owing to the creases perceptibly. Sea. The western limits strong re-sprouting ability of its The species is he- of its range are in France, coppiced stands. In the past, it liophilous; in full light, while the northern limits run was widely used for railway sleep- the growth rate is par- across southeast Switzer- ers, now these remains only for a ticularly fast, especially land, eastern Austria, northern small proportion of the logs final that of the sprouts. Par- Czech Republic and Slovakia. destination. Indeed, the current tial shade is tolerated, It is widely distributed in Slove- importance of Q. cerris relies in its however. Turkey oak nia, especialy in the sub-Med- major ecological role. Turkey oak prefers basic, deep, iterranean and pre-Pannonian has diverse types of interactions fresh soils, but it regions, in predominantly pure with ectomycorrhizal fungi, gall- is highly tolerant stands and as single trees in forming insects and seed-eating to almost any soil mixed broadleaf stands. vertebrates. Its forests contrib- (except very wet It is common in the ute to biodiversity safeguard soil). Turkey oak Italian peninsula and in the temperate regions also tolerates strong winds, in the Balkan area, providing habitats for but not maritime exposure. It from Croatia and numerous plant and forms both pure and mixed southern Austria animal communi- stands, mainly with other oaks. to Hungary, up to ties, including verte- Pure populations with an an- northern Greece brates, arthropods, thropic origin are common. It and the Bulgar- greens and epi- may show a sporadic occur- ian and Romanian phytes. rence in Mediterranean ever- Black Sea coasts. It is possible to see green forests, where summer In Turkey there are pure managed stands drought is not a limiting factor. two different subspecies. and mixed forests with Q. cerris is found from the low- It also occurs in south and east different Quercus species (Q. lands up to about 1500 m above Anatolia (reaching Erzincan), up frainetto, Q pubescens, Q. infec- sea level, in Anatolia mostly be- to Samsun in Northern Ana- toria, Q. petrea, Q libani), other tween 500-2000 m, in Lebanon tolia and the Aegean coast of broad leaved species (Fagus, between 1300 and 2200 m. Turkey. Castanea, Carpinus) and conifers TurkeyQuercus oakQuercus cerrisTurkey oakQuercus cerris Turkeycerris oakQuercus cerrisTurkey QuercusoakQuercus cerrisTurkey oakQuercus cerrisTurkey cerris oakQuercus cerrisTurkey oak QuercusQuercus cerrisTurkey oakQuercus cerrisTurkey oakcerrisQuercus cerrisTurkey oakQuercus Quer cerrisTurkey oakQuercus cerri (Pinus nigra, Pinus brutia, Pinus Genetic knowledge and Balkan populations was pinea). There are also monumen- probably caused by a marked tal individuals with symbolic value population contraction during widely occurring in many old vil- It is commonly agreed that, a glacial phase of the Middle lages across Europe as part of the during the last ice age, the natu- Pleistocene. In Italy, Q. cerris local heritage. ral range of oak species was shares the two most common In past times, the seeds were mainly restricted to the Iberian, haplotypes with Q. suber, thus cooked, dried, ground into pow- Italian and Balkan peninsulas. indicating the possible retention der and used as a thickening During the postglacial period of ancestral variation or unidi- agent in stews or mixed with ce- (approximately the last 7000 rectional introgression between reals for bread-making. The seed years), oaks recolonized their Turkey oak (as seed parent) contains bitter tannins, which can present range from the different and cork oak (pollen parent). In be leached out by washing the refuge areas. These movements Anatolia, an extensive investi- seed thoroughly in running water. have basically impacted the ge- gation with nuclear microsatel- The roasted seeds were also used netic diversity distribution. Ac- lites revealed the occurrence of as a coffee substitute. Other uses cordingly, recent data based on two different gene pools, with concern the seed cups, leaves, plastid microsatellites across low and high genetic diversity bark and wood, commercially the whole species’ range show (the northern and south-cen- used as a source of tannins. Fi- an important level of popula- tral region, respectively). The nally, Quercus cerris can be ef- tion divergence, with the high- false cork oak (Quercus crenata ficiently used in the establishment est genetic diversity within the Lam.), scattered in Italy, south- of truffle orchards, or trufferies. Balkan area and the presence ern France, Slovenia and Croa- Truffles (Tuber melanosporum of unique lineages in the far tia is considered the resulting Vitt., T. magnatum Pico, T. aesti- eastern range (Bagnoli et al. hybrid between Q. cerris and vum L.) grow in an ectomychor- 2016). Three genetically and the cork oak (Quercus suber rizal association with the tree's geographically distinct L.). Based on morphological roots. clusters were identified: intermediacy and some pre- a Western (Italian penin- liminary genetic studies, other sula and Northwestern less frequent hybrids are those Balkan region), a Cen- suggested with other eastern tral (Central and south- Mediterranean oaks such as ern Balkans), and an Q. libani Oliv. (Q. x libanerris Eastern group (Anatolia Boom.), Q. trojana Webb. (Q. and Middle East). Fossil x schneideri Viehr.), Q. pube- data and approximate Bayes- scens (Q. x baenitzii A.Camus), ian computation analysis in- Q. brantii Lindl., Q. infectoria dicate a possible bottleneck Oliv. and Q. ithaburensis Dec- leading to the divergence ne. (Özer, 2014). However, a of the Eastern and Cen- clear assessment of the hybrid- tral populations in the ization ability of the Turkey oak Early Pleistocene. The and validation of its presumed split between the Italian hybrids are still missing. TurkeyQuercus oakQuercus cerrisTurkey oakQuercus cerris Turkeycerris oakQuercus cerrisTurkey QuercusoakQuercus cerrisTurkey oakQuercus cerrisTurkey cerris oakQuercus cerrisTurkey oak QuercusQuercus cerrisTurkey oakQuercus cerrisTurkey oakcerrisQuercus cerrisTurkey oakQuercus Quer cerrisTurkey oakQuercus cerri Threats to Guidelines for genetic In high forests for production, even-aged populations are pre- genetic diversity conservation and use ferred, in order to reduce com- Humans have greatly reduced Concerning Q. cerris wild petition among individuals of dif- the natural distribution of oaks in populations, special care should ferent sizes. Since Turkey oak the past, and most oak forests be taken regarding habitat con- wood is not valuable, high forest have