Reflecting KFBG’s former incarnation as the Kadoorie Agricultural Aid Association (KAAA), much of our terraced land is still planted up with fruit orchards. As farming declined in Hong Kong through the 1980s, and as KAAA gave way to KFBG in 1995, our focus shifted to nature conservation and many of our orchard terraces became unproductive. In line with our present mission and vision, we aspire to convert these abandoned orchards into ecologically functional, high diversity native forest.
This is far easier said than done. The retaining terrace walls preclude natural slope hydrology and soil formation. The underlying substrate is an eroded matrix of clay and aggregate, and any topsoil there may once have been has long been washed away. This makes the ground exceptionally dry and infertile. The fruit trees (mostly longan and lychee) are densely planted and occupy more-or-less all of the available planting space. Restoring these terraces therefore demands that we firstly tackle these constraints.
To make the challenge more manageable, we begun by selecting a subset of the terraces to restore first. Our tree teams work to prune and thin out the existing fruit trees within these orchards to create planting space. Some are retained to serve as nurse trees to the seedlings we plant beneath, but they too will ultimately be replaced by native species. Crucially, we apply a mulch mixture to the soil surface to improve soil quality prior to tree planting. Wherever possible, we plan to demolish old or partially collapsed stonewalls to recreate natural slope surfaces.
Once these preparatory works have been completed, we decide on the most suitable tree species to be planted. This depends on features including growth habit, habitat preference, sunlight and water requirements, and so on. We also keep an eye on overall species diversity. Upon planting, we inspect the root system of each seedling and undertake root pruning to remove diseased, deformed and girdling roots. After planting and backfilling the soil, tree guards are installed. We monitor the growth of the planted seedlings and undertake maintenance and enhancement planting from time to time.
It is truly inspiring to see new native forest take root. Our initial objective is to reconnect scattered patches of good forest across the KFBG site by rejuvenating the abandoned orchard terraces as green corridors. In time, the fragments will become one contiguous block featuring high species diversity and delivering important ecological services.