Road sides in Hong Kong are usually open, disturbed, and strongly influenced by surrounding hard surfaces such as asphalt, concrete, walls, and buildings. Even when the weather is cloudy or humid, roadside microhabitats are still stressful for plants because the soil is often compacted, and the drainage is poor or irregular. Plants growing in this microclimate may be affected by trampling, pollution, traffic, litter, and heat stored by nearby surfaces. After rain, roadsides may become temporarily wet, but they can also dry quickly if water runs off the pavement instead of entering the soil. On these road sides, the plants growing there are way smaller and are usually resumed to yellowing and moss of the concrete ground due to poor drainage.
Tree pits in Hong Kong usually are managed and controlled microhabitats rather than rich spontaneous plant communities. While tree pits could have been very good microclimates for plants to grow, due to the direct sunlight given my the tree trunk and it leaves as well as the accessibility to soil and nutrients, in Hong Kong many of these contain very few plants besides the planted tree, because the soil is often cleaned, compacted, or cleared when weeds and small herbs become too tall. This is interesting because it reflects human management, restricted rooting space, soil disturbance, or regular removal rather than unsuitable climate alone.