In plant ecology, the terms growth and development are often used interchangeably. Yet these constitute two distinct processes. Plant architectural traits (e.g. number of successive forks) can estimate development stages. Here, we show the importance of including the effect of development stages to better understand size-related trait scaling relationships (i.e. between height and stem diameter). We focused on one common savanna woody species (Senegalia nigrescens) from the Greater Kruger Area, South Africa. We sampled 406 individuals that experience different exposure to herbivory, from which we collected four traits: plant height, basal stem diameter, number of successive forks (proxy for development stage), and resprouting. We analysed trait relationships (using standardized major axis regression) between height and stem diameter, accounting for the effect of ontogeny, exposure to herbivory, and resprouting. The number of successive forks affects the scaling relationship between height and stem diameter, with the slope and strength of the relationship declining in more developed individuals. Herbivory exposure and resprouting do not affect the overall height-diameter relationship. However, when height and stem diameter were regressed separately against number of successive forks, herbivory exposure and resprouting had an effect. For example, resprouting individuals allocate more biomass to both primary and secondary growth than non-resprouting plants in more disturbed conditions. We stress the need to include traits related to ontogeny so as to disentangle the effect of biomass allocation to primary and secondary growth from that of development in plant functional relationships.

Centre for African Ecology School of Animal Plant and Environmental Sciences University of the Witwatersrand Johannesburg South Africa

Department of Botany and Zoology Faculty of Science Masaryk University Brno Czechia

Environmental Change Institute School of Geography and the Environment University of Oxford Oxford UK

Institute of Botany The Czech Academy of Sciences Třeboň Czechia

National Biodiversity Future Center Palermo Italy

Research Institute on Terrestrial Ecosystems Porano Italy

School for Climate Studies Stellenbosch University Matieland South Africa

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Archibald S., Bond W.J. (2003) Growing tall vs growing wide: tree architecture and allometry of Acacia karroo in forest, savanna, and arid environments. Oikos, 102, 3–14.

Barthélémy D., Caraglio Y. (2007) Plant architecture: a dynamic, multilevel and comprehensive approach to plant form, structure and ontogeny. Annals of Botany, 99, 375–407.

Bond W.J., Midgley J.J. (2001) Ecology of sprouting in woody plants: the persistence niche. Trends in Ecology & Evolution, 16, 45–51.

Bond W.J., Midgley J.J. (2003) The evolutionary ecology of sprouting in woody plants. International Journal of Plant Sciences, 164, S103–S114.

Bossu J., Lehnebach R., Corn S., Regazzi A., Beauchêne J., Clair B. (2018) Interlocked grain and density patterns in Bagassa guianensis: changes with ontogeny and mechanical consequences for trees. Trees, 32, 1643–1655.

Cavender‐Bares J., Bazzaz F.A. (2000) Changes in drought response strategies with ontogeny in Quercus rubra: implications for scaling from seedlings to mature trees. Oecologia, 124, 8–18.

Charles‐Dominique T., Edelin C., Bouchard A., Legendre P., Brisson J. (2015b) Using intra‐individual variation in shrub architecture to explain population cover. Oikos, 124, 707–716.

Charles‐Dominique T., Staver A.C., Midgley G.F., Bond W.J. (2015a) Functional differentiation of biomes in an African savanna/forest mosaic. South African Journal of Botany, 101, 82–90.

Clarke P.J., Lawes M.J., Midgley J.J., Lamont B.B., Ojeda F., Burrows G.E., Enright N.J., Knox K.J.E. (2013) Resprouting as a key functional trait in woody plants—challenges to developing new organizing principles. New Phytologist, 197, 19–35.

Dayrell R.L., Arruda A.J., Pierce S., Negreiros D., Meyer P.B., Lambers H., Silveira F.A. (2018) Ontogenetic shifts in plant ecological strategies. Functional Ecology, 32, 2730–2741.

Dharani N. (2006) Field guide to Acacias of East Africa. Struik, Cape Town, South Africa, pp 200.

Diggle P.K. (2002) A developmental morphologist's perspective on plasticity. Evolutionary Ecology, 16, 267–283.

Fajardo A., Mora J.P., Robert E. (2020) Corner's rules pass the test of time: little effect of phenology on leaf–shoot and other scaling relationships. Annals of Botany, 126, 1129–1139.

Fornara D.A., Du Toit J.T. (2007) Browsing lawns? Responses of Acacia nigrescens to ungulate browsing in an African savanna. Ecology, 88, 200–209.

Hallé F., Oldeman R.A.A., Tomlinson P.B. (1978) Tropical trees and forests. Springer, Berlin, Germany, pp 441p.

He D., Yan E.‐R. (2018) Size‐dependent variations in individual traits and trait scaling relationships within a shade‐tolerant evergreen tree species. American Journal of Botany, 105, 1165–1174.

Keeley J.E., Pausas J.G., Rundel P.W., Bond W.J., Bradstock R.A. (2011) Fire as an evolutionary pressure shaping plant traits. Trends in Plant Science, 16, 406–411.

Lamont B.B., He T. (2017) Fire‐proneness as a prerequisite for the evolution of fire‐adapted traits. Trends in Plant Science, 22, 278–288.

Lehnebach R., Beyer R., Letort V., Heuret P. (2018) The pipe model theory half a century on: a review. Annals of Botany, 121, 773–795.

Magnin A., Torres C., Stecconi M., Villalba R., Puntieri J. (2022) Influence of trunk forking on height and diameter growth in an even‐aged stand of Nothofagus pumilio. New Zealand Journal of Botany, 60, 45–59.

Moncrieff G.R., Chamaillé‐Jammes S., Higgins S.I., O'Hara R.B., Bond W.J. (2011) Tree allometries reflect a lifetime of herbivory in an African savanna. Ecology, 92, 2310–2315.

Nozeran R. (1978) Multiple growth correlations in phanerogams. In: Tomlinson P.B., Zimmermann M.H. (Eds), Tropical trees as living systems. Cambridge University Press, Cambridge, UK, pp 423–443.

Osborne C.P., Charles-Dominique T., Stevens N., Bond W.J., Midgley G., Lehmann C.E. (2018) Human impacts in African savannas are mediated by plant functional traits. New Phytologist, 220, 10–24.

Palgrave K.C. (2002) Trees of Southern Africa, revised and updated. Struik, Cape Town, South Africa, pp 959.

Pausas J.G., Keeley J.E. (2014) Evolutionary ecology of resprouting and seeding in fire‐prone ecosystems. New Phytologist, 204, 55–65.

Pausas J.G., Lamont B.B., Paula S., Appezzato‐da‐Glória B., Fidelis A. (2018) Unearthing belowground bud banks in fire‐prone ecosystems. New Phytologist, 217, 1435–1448.

Poethig R.S. (2003) Phase change and the regulation of developmental timing in plants. Science, 301, 334–336.

R Core Team. (2020) R: a language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. Available from https://www.R-project.org/ (3 November 2022).

Reich P.B., Ellsworth D.S., Walters M.B., Vose J.M., Gresham C., Volin J.C., Bowman W.D. (1999) Generality of leaf trait relationships: a test across six biomes. Ecology, 80, 1955–1969.

Shinozaki K., Yoda K., Hozumi K., Kira T. (1964) A quantitative analysis of plant form – The pipe model theory: I. Basic analyses. Japanese Journal of Ecology, 14, 97–105.

Staver A.C., Bond W.J. (2014) Is there a ‘browse trap’? Dynamics of herbivore impacts on trees and grasses in an African savanna. Journal of Ecology, 102, 595–602.

Stillwell R.C., Shingleton A.W., Dworkin I., Frankino W.A. (2016) Tipping the scales: evolution of the allometric slope independent of average trait size. Evolution, 70, 433–444.

Tomlinson P.B., Esler A.E. (1973) Establishment growth in woody monocotyledons native to New Zealand. New Zealand Journal of Botany, 11, 627–644.

Van Wilgen B.W., Biggs H.C., O'Regan S.P., Mare N. (2000) A fire history of the savanna ecosystems in the Kruger National Park, South Africa, between 1941 and 1996. South African Journal of Science, 96, 167–178.

Venter F.J., Scholes R.J., Eckhardt H.C. (2003) The abiotic template and its associated vegetation pattern. In: Du Toit J.T., Rogers K.H., Beggs H.C. (Eds), The Kruger experience: ecology and management of savanna heterogeneity. Island Press, Washington DC, USA, pp 83–129.

Wakeling J.L., Staver A.C., Bond W.J. (2011) Simply the best: the transition of savanna saplings to trees. Oikos, 120, 1448–1451.

Warton D.I., Wright I.J., Falster D.S., Westoby M. (2006) Bivariate line-fitting methods for allometry. Biological Reviews of the Cambridge Philosophical Society, 81, 259–291.

Warton D.I., Duursma R.A., Falster D.S., Taskinen S. (2012) smatr 3– an R package for estimation and inference about allometric lines. Methods in Ecology and Evolution, 3, 257–259.

West G.B., Brown J.H., Enquist B.J. (1999) A general model for the structure and allometry of plant vascular systems. Nature, 400, 664–667.

Westoby M., Falster D.S., Moles A.T., Vesk P.A., Wright I.J. (2002) Plant ecological strategies: some leading dimensions of variation between species. Annual Review of Ecology and Systematics, 33, 125–159.

Wigley B.J., Charles‐Dominique T., Hempson G.P., Stevens N., TeBeest M., Archibald S., Bond W.J., Bunney K., Coetsee C., Donaldson J., Fidelis A., Gao X., Gignoux J., Lehmann C., Massad T.J., Midgley J.J., Millan M., Schwilk D., Siebert F., Solofondranohatra C., Staver A.C., Zhou Y., Kruger L.M. (2020) A handbook for the standardised sampling of plant functional traits in disturbance‐prone ecosystems, with a focus on open ecosystems. Australian Journal of Botany, 68, 473–531.

World Flora Online. (2022) http://www.worldfloraonline.org/ (15 September 2022).

Yoganand K., Owen‐Smith N. (2014) Restricted habitat use by an African savanna herbivore through the seasonal cycle: key resources concept expanded. Ecography, 37, 969–982.