J. For. Sci., 2026, 72(9):441-454 | DOI: 10.17221/49/2026-JFS

Morpho‑physiological traits and biomass scaling of the invasive Callery pear (Pyrus calleryana Decne.)Original Paper

Prabina Sharma1, David R. Coyle1, James F. Palmer1, Nilesh Timilsina1, Jessica Hartshorn2
1 Department of Forestry and Environmental Conservation, Clemson University, Clemson, USA
2 Agricultural Research Development Program, Central State University, Wilberforce, USA

Accurately estimating aboveground biomass (AGB) of invasive plant species is essential for understanding their prevalence, ecological impacts, and informed management strategies. Pyrus calleryana (Callery pear) is established throughout the eastern United States, yet species-specific biomass models and physiological trait data remain limited. We destructively sampled 40 single-stem trees with diameter at breast height (DBH) ranging from 1.2 cm to 17.7 cm and height from 1.6 m to 10.3 m across six sites in South Carolina to quantify dry biomass, moisture content (MC), Carbon and Nitrogen ratios (C : N), and to develop allometric equations for predicting total AGB. The DBH-based log–linear model provided the strongest overall fit for total AGB (R2 = 0.91; bias = 0.41 kg), and hold-out validation indicated strong predictive performance for unobserved trees (root mean square error, i.e. RMSE = 5.59 kg; validation R2 = 0.967). Tissue traits differed significantly: leaves had the highest moisture content, whereas stems had the highest C : N ratio and AGB. These findings provide a practical, biologically interpretable DBH-based equation and biomass data suitable for forest inventory applications and invasion monitoring. The study also establishes baseline physiological parameters for P. calleryana, supporting improved evaluation of its ecological footprint and management needs.

Keywords: allometric modelling; Bradford pear; carbon; moisture content; South Carolina

Received: June 15, 2026; Revised: August 20, 2026; Accepted: August 31, 2026; Published: September 30, 2026  Show citation

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Sharma P, Coyle DR, Palmer JF, Timilsina N, Hartshorn J. Morpho‑physiological traits and biomass scaling of the invasive Callery pear (Pyrus calleryana Decne.). Journal of Forest Science. 2026;72(9):441-454. doi: 10.17221/49/2026-JFS.
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