For centuries, stem cuttings harvested from sexually mature trees have been recognized to be more difficult to root than those from juvenile shoots. This has been poorly understood and attributed to a combination of ontogenetic and physiological ageing. The recent suggestion that micro-RNA may play a key role in phase change has stimulated a re-examination of some old data that identified pre-severance light x nutrient interactions affecting the rooting ability of stem cuttings. This was linked to vigorous growth and active photosynthesis without constraint from accumulated starch. Support for the prime importance of physiological factors was also obtained when seeking to induce physiological youth in the crowns of ontogenetically mature trees by the induction of roots within the tree crown. Meanwhile, at the other end of the phase change spectrum, floral initiation occurred when the opposite set of environmental conditions prevailed so that growth was stunted, and carbohydrates accumulated in leaves and stems. A re-examination of this literature suggests that rooting ability is driven at the level of an individual leaf and internode emerging from the terminal bud affecting both morphological and physiological activity. In contrast, flowering occurs when internode elongation and assimilate mobilization were hindered. It is therefore suggested that the concepts of juvenility and ageing are not relevant to vegetative propagation and should instead be replaced by physiological and morphological ‘fitness’ to root.

With the intensification of the aging population trend, China is facing an increasingly growing demand for older adult care services. As an important field that meets the needs of the older adult, the development of the older adult care service industry is of significant importance for social stability and the well-being of the older adult. This paper examines the trends and optimization paths of the older adult care service industry in China. It aims to analyze the current situation, problems, and causes of the industry, and propose corresponding policy adjustment recommendations. Through comparative analysis of scholars’ viewpoints, the paper redefines the connotation and scope of the older adult care service industry, emphasizing the characteristics of its compound industrial system. The analysis reveals that the current Chinese older adult care service industry is characterized by a small scale, single functionality, narrow coverage, short industrial chain, and a lack of policy support and rational resource allocation. Policy adjustment recommendations are proposed, including top-level institutional design, improvement of the social security system, and the formation of a comprehensive industrial system, in order to promote the development of the older adult care service industry. These recommendations not only promote the expansion of industry scale and the expansion of functionality, but also enhance the quality and effectiveness of older adult care services to meet the diverse needs of the older adult. The value of this paper lies in its in-depth analysis of the current situation of the older adult care service industry in China and the proposal of specific and feasible policy adjustment recommendations, providing important guidance for government departments and practitioners. The research findings can provide beneficial references for the sustainable development of the older adult care service industry, further promoting the progress of the social economy and the healthy development of an aging society.