Log in

Editor's Picks

Emory oak near Young, Arizona © Nanebah Lyndon
Emory oak acorns are a critically important commodity for...
Website Editor | Feb 12, 2021
Ecological Landscape Alliance
Murphy Westwood and Tim Boland presented on oak diversity...
Website Editor | Feb 12, 2021
Keiko Tokunaga's Illustrated Fagaceae
Shaun Haddock reviews Keiko Tokunaga's latest book.
Shaun Haddock | Feb 09, 2021

Plant Focus

Quercus texana New Madrid acorn
Disentangling the cultivar published as Quercus texana ‘New Madrid’

Functional Diversification in the “Roburoid” and “Cerris” Oaks

PDF icon Full text available for IOS members only. If you are a member, you need to log in.

To create an account click here; if you have already registered, click here to become a member.

Individual articles can be purchased for U$S 10. If you would like to purchase an article, email a request to website@internationaloaksociety.org

J.A. Ramírez-Valiente, R. López, and I. Aranda

Published May 2019 in International Oaks No. 30: 117–124


Climate is a critical factor of selection for forest tree species. Disentangling the functional mechanisms underlying climate adaptation is essential to understand current species distributions and predict future patterns under changing climatic conditions. In this study, we assessed whether drought resistance and growth potential have evolved as a result of climate adaptation in European/North African oaks (Quercus spp.), and explored a potential trade-off between functional strategies. Our hypothesis is that oaks have evolved towards increasing resistance to water deficit at the southern range as a result of selective pressures imposed by summer drought whereas a selection towards increasing growth potential has occurred in high productive areas of central Europe characterized by mesic summers. To test this hypothesis, we conducted a greenhouse experiment where seedlings originating from 11 oak species were subjected to contrasting watering regimes. Our study revealed differences among oak species in traits related to growth and drought resistance. On average, species originating from climates with more severe dry seasons exhibited more sclerophyllous leaves with lower specific leaf area, mass-based photosynthetic rates and relative growth rates at the beginning of the growing season. Importantly, xeric species had higher growth rates at the end of the growing season and lower native embolism. A trade-off was observed between mass-based photosynthetic rates and native loss of hydraulic conductivity across treatments, indicating that species with higher growth potential are more vulnerable to xylem cavitation. Overall, our results showed that functional strategies are associated with the climate of origin in European/North African oaks.


drought tolerance, climate adaptation, functional strategies, trade-offs


Corcuera, L., J.J. Camarero, and E. Gil-Pelegrinet. 2002. Functional groups in Quercus species derived from the analysis of pressure–volume curves. Trees 16: 465-472.

Lobo, A., J.M. Torres-Ruiz, R. Burlett, C. Lemaire, C. Parise, C. Francioni, L. Truffaut, I. Tomaskova, J.K. Hansen, E.D. Kjaer, A. Kremer, and S. Delzon. 2018. Assessing inter-and intraspecific variability of xylem vulnerability to embolism in oaks. Forest ecology and management 424: 53-61.

Mahall, B.E., C.M. Tyler, E.S. Cole, and C. Mata. 2009. A comparative study of oak (Quercus, Fagaceae) seedling physiology during summer drought in southern California. American Journal of Botany 96: 751-761.

Quero, J.L., R. Villar, T. Marañón, R. Zamora, D. Vega, and L. Sack. Relating leaf photosynthetic rate to whole-plant growth: drought and shade effects on seedlings of four Quercus species. Functional Plant Biology 35: 725-737.

Skelton, R.P., T.E. Dawson, S.E Thompson, Y. Shen, A.P. Weitz, and D. Ackerly. 2018. Low vulnerability to xylem embolism in leaves and stems of North American oaks. Plant Physiology 177: 1066-1077.

Tilman, D. 1988. Plant strategies and the dynamics and structure of plant communities. Princeton, NJ: Princeton University Press.

Torres-Ruiz, J.M., S. Jansen, B. Choat, A.J. McElrone, H. Cochard, T.J. Brodribb, E. Badel, R. Burlett, P.S. Bouche, C.R. Brodersen, S. Li, H. Morris, and S. Delzon. 2015 Direct X-ray microtomography observation confirms the induction of embolism upon xylem cutting under tension. Plant Physiology 167: 40-43.

Peguero-Pina, J.J., S. Sisó, J. Flexas, J. Galmés, Ana Farcía-Nogales, U. Niinemets, D. Sancho-knapik, M.A. Saz, E. Gil Pelegrín. 2017. Cell‐level anatomical characteristics explain high mesophyll conductance and photosynthetic capacity in sclerophyllous Mediterranean oaks. New Phytologist 214: 585-596.