02733naa a2200313 a 450000100080000000500110000800800410001902400520006010000180011224501460013026000090027652018060028565000170209165000170210865000130212565000120213865000170215065300190216765300230218670000190220970000220222870000250225070000200227570000170229570000210231270000240233370000240235777300380238121590062023-12-01       2023    bl uuuu     u00u1 u    #d7 ahttps://doi.org/10.1007/s00468-023-02443-z2DOI1 aMORAES, L. G.  aForking and planting spacing impacts on wood density, X‑ray density, and heartwood proportion of Tachigali vulgaris.h[electronic resource]  c2023  aPromising Amazonia species for forest energy crops require further investigation into how silviculture affects wood quality. This study sought to investigate how planting spacing and stem type (forked and non-forked) affect the basic wood density, X-ray density, and heartwood development of Tachigali vulgaris in a homogeneous plantation in Amazonia. The experiment was established with initial planting spacings of 3.0 × 1.5 m, 3.0 × 2.0 m, 3.0 × 2.5 m, 3.0 × 3.0 m, 3.0 × 3.5 m, and 3.0 × 4.0 m. 102-month-old trees were harvested for the work. Disks sampled along the stem height were tested for wood basic density and density measured by X-ray densitometry (air-dry density by growth ring) analyses. Disks obtained at the 1.3 m height were photographed and submitted to image manipulation for heartwood/sapwood analysis. The lowest average wood density was 0.512 g cm−3 in the 3.0 × 1.5 m spacing, and the highest was 0.538 g cm−3 in the 3.0 × 4.0 m spacing. Among non-forked trees, 66% had medium-density (≥ 0.500 g cm−3) and 34% low-density (&lt 0.500 g cm−3) wood. In contrast, forked trees had only 55% of trees with medium-density wood. The X-ray density profiles reduced from 0.713 to 0.582 g cm−3 in the increasing longitudinal direction and from 0.393 to 0.973 g cm−3 in the radial direction. Forking did not influence the heartwood proportion (60.03–61.54%). The 3.0 × 3.0 m spacing favored the wood quality concerning density class and variability, while the widest spacings improved heartwood formation. The forking increases the chances of low-density wood and its variations along the stem. Thus, future genetic studies should focus on this phenomenon to increase the productivity of Tachigali vulgaris energy forests.  aSilviculture  aWood quality  aFloresta  aMadeira  aSilvicultura  aEnergy forests  aTachigali vulgaris1 aLIMA, M. D. R.1 aASSIS-PEREIRA, G.1 aGONÇALVES, D. de A.1 aVIDAURRE, G. B.1 aBUFALINO, L.1 aGUEDES, F. T. P.1 aTOMAZELLO-FILHO, M.1 aPROTÁSIO, T. de P.  tTreesgv. 37, p. 1567-1581, 2023.