A pesquisa teve como objetivo avaliar o uso de hidrogel na sobrevivência de mudas clonais de Eucalyptus urograndis produzidas com diferentes substratos e manejos hídricos. O experimento foi conduzido com mudas do mesmo clone, produzidas até os 50 dias após estaqueamento em dois viveiros distintos ("C" e "E"). Em seguida, todas as mudas foram alocadas num mesmo viveiro, durante 80 dias as quais receberam diferentes frequências de irrigação. Após esse período, as mudas foram transplantadas para vasos de polietileno, em solo argiloso, com e sem hidrogel. Os resultados obtidos foram submetidos à técnica de variância para experimentos inteiramente casualizado. A análise dos dados permitiu inferir que as plantas com hidrogel tiveram seus sintomas de falta de água retardados. Independentemente da origem da muda ("C" ou "E"), o hidrogel, exerceu influência na sobrevivência, garantindo 37 dias sem irrigação adicional. O manejo hídrico do viveiro exerceu influência somente para as mudas denominadas "E", sendo que plantas adaptadas à falta de água (manejo hídrico com uma irrigação diária) demoraram mais tempo para apresentar sintomas de déficit hídrico. Palavras-chave: eucalipto; polímero hidro absorvente; irrigação; plantio.

Soil influences the growth of trees and the characteristics of the wood; but could this influence change during the ontogeny of trees? To answer this question, we analyzed the wood anatomy of 9-year-old trees and 2-year-old saplings of Enterolobium contortisiliquum, known as “tamboril”, growing in eutrophic and oligotrophic soil in the Brazilian Cerrado, and assessed the effect of age on plant–soil relationship. Sapwood samples were collected from the main stem, anatomical sections were prepared in the lab, and 12 anatomical wood traits were measured. Individuals in eutrophic soil had greater stem diameter and height than those in oligotrophic soil. Trees in eutrophic soil had vessel-associated parenchyma cells with abundant storage compounds. Fibers walls were 47% thicker and intervessel pits diameter were 14% larger in trees of eutrophic soil. A greater proportion of solitary vessels (74%) was observed in trees rather than in saplings (50%). The secondary xylem of trees was mainly formed by fibers (63%) whereas in saplings it was mainly formed by storage tissue (64%). Our study provides evidence that the influence of soil conditions on tree growth reflects variations in wood anatomical features. No significant response to soil type was observed in saplings, thus demonstrating that the relationship between soil type and wood growth is mediated by tree age. These findings help to develop reliable reforestation strategies in tropical ecosystems characterized by different levels of soil fertility.

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The Public Garden of São Manuel was remodeled in 1928 by the Paulista landscaper Reynaldo Dierberger (1899-1977) and executed by the firm Dierberger & Cia, founded in 1893 in the city of São Paulo by the family' patriarch, João Dierberger. This firm was, until the 1940s, one of the most important ones in the production and commercialization of plants, projects, and execution of gardens. The project elaborated for São Manuel has particular importance for being one of the rare gardens executed by the firm Dierberger, still preserved in its structural aspects. The garden is also a testimony of São Manuel's history since its birth. Furthermore, there is a blueprint of the original project, with handwritten notes by the author about the plant species to be used in this garden. So far, this is the only author's project found in São Paulo´s state, among hundreds of projects, where there is a specification of the vegetation. In this context, the present study aimed to identify and locate the remaining trees and palms of the 1928 project that still exist today. The research used the remodeling project´s blueprint, historical iconography, dissertations, articles, and the georeferenced botanical survey (February 2022). The results show that most of the trees and palm are no longer present or have been replaced by other species and that the upper part of the garden is the one that still preserves part of the vegetal composition.