The study of canopy structures is essential for the precise management of local forage. Although the relationship between the canopy height (CH) and light interception (LI) allows the best use of forage, there are other characteristics of the canopy that, if not observed, can lead to errors in grazing management. This study analyzes the effect of the defoliation frequencies (DF) and season on the productive and structural characteristics of Guinea grass and defines whether tiller population density (TPD) should be considered in the mathematical models that relate CH to LI. The experimental design used includes randomized blocks with six defoliation frequencies (DF) of 14, 21, 28, 35, 42, and 49 days, over three seasons: rainy season 2015 (RS2015), dry season (DS), and rainy season 2016 (RS2016), in the Amazon biome. Yield characteristics and forage structure were evaluated. The interaction between the DFs and seasons in all evaluated variables included forage accumulation, proportions of stem, leaves and dead material, tiller population density (TPD), CH, LI, and leaf area index. The curve steepness constant (CSC) of the nonlinear models between CH and LI was different from that of the DFs. A DF of 14–28 days averaged a TPD of 616 tillers m⁻² and CSC of 0.0407, and a DF of 35–49 days averaged a TPD of 496 tillers m⁻² and CSC of 0.0368. An agreement index (d) of 0.87, a bias of 1.5 %, and a determination coefficient (R²) of 0.6187 were obtained for the model that estimated a CH with the inclusion of LI and TPD when validated with data from studies published in the literature. TPD associated with CH and LI allowed for more precise management of the ideal defoliation moment.

冠层结构的研究对于当地牧草的精确管理至关重要。尽管冠层高度 (CH) 和遮光率 (LI) 之间的关系允许最好地利用草料，但冠层的其他特征如果不加以观察，可能会导致放牧管理出现错误。本研究分析了落叶频率 (DF) 和季节对几内亚草生产和结构特征的影响，并定义了在将 CH 与 LI 相关的数学模型中是否应考虑分蘖种群密度 (TPD)。使用的实验设计包括具有 14、21、28、35、42 和 49 天的六个落叶频率 (DF) 的随机块，三个季节：2015 年雨季 (RS2015)、旱季 (DS) 和 2016 年雨季（RS2016），在亚马逊生物群系。评价了产量特性和草料结构。所有评估变量中 DF 和季节之间的相互作用包括草料积累、茎、叶和死物质的比例、分蘖种群密度 (TPD)、CH、LI 和叶面积指数。CH 和 LI 之间非线性模型的曲线陡度常数 (CSC) 与 DF 不同。14-28 天的 DF 平均 TPD 为 616 分蘖 m^-2和 CSC 为 0.0407，35-49 天的 DF 平均 TPD 为 496 分蘖 m ^-2和 CSC 为 0.0368。当使用文献中发表的研究数据进行验证时，该模型的一致性指数 (d) 为 0.87，偏差为 1.5 %，决定系数 (R²) 为 0.6187，该模型估算了包含 LI 和 TPD 的 CH . 与 CH 和 LI 相关的 TPD 允许更精确地管理理想的落叶时刻。