Leave the Christmas berry mulch or remove it?
Just beginning a land project on the big Islands Southside district of KAU
Rather thin soil layer with lots of lava rock under
The property is almost entirely overrun with Christmas berry, Schinus terebinthifolia, which we understand has toxic sap
We're going to do a land clearing and we have option to have the Christmas berry turned into mulch and left there or removing it. Would you have any recommendations about how we start our soil?
Top answer
Mulching it and concentrating the wood chips in the area you will be growing in is what I recommend. Even though it has toxic sap, that will quickly be broken down by microbes and will not inhibit the effectiveness of it as a mulch. You want to be careful not to scrape up too much of the thin soil you have, so adding a thick layer of mulch will help build more soil where you need it. Also be careful of erosion after clearing, and the subsequent weeds/grasses that will thrive when the land has been cleared.
I also recommend going slow and steady, and instead of clearing the land and getting rid of all the trees, doing it slowly, clearing only what is necessary at the time, and planting in between your existing cover, and as those trees grow, clearing out the christmas berry. This is a huge carbon store for you, and if it is all dropped at one time, it will quickly (within a year) be gone and then you will have to grow other things or import mulch to keep up the fertility of the area.
Also, think of the christmas berry as a resource, as I mentioned today in the Office Hour, Richard Perea used to use the christmas berry very effectively when he was living out in the Kau region.
From the KNF library
From the KNF library
Drafted by Claude from Office Hours and the books
·
Sep 2026
·
5 sources
Drake recommends removing Christmas berry slowly and planting behind it, not clearing all at once. (Office Hours Ep. 44, 41:15) The library's weed guidance agrees. Keep the soil covered, and remove plants only when something beneficial can replace them. (KNF Demystified, p. 12)
For growing in rock, the library says to begin by building upward. (KNF Demystified, p. 42) Add green waste, keep the area inoculated with microbes, and mulch regularly. (KNF Demystified, p. 42) Roots then pierce the rock and unlock fertility. (KNF Demystified, p. 42)
Inoculate the chips:
- Add microbes when you add mulch, to avoid carbon-nitrogen depletion. (KNF Demystified, p. 16)
- Pre-inoculate the mulch with IMO4. (KNF Demystified, p. 16)
- Stop tilling. Mulch and apply IMO4 to rebuild the soil microbiome. (Office Hours Ep. 58, 47:06)
The library does not cover the toxic sap or lava rock by name.
Sources
- 41:15 Office Hours Ep. 44 (Aug 2022) — LAB Troubleshooting, Bacillus Subtilis Probiotics, Fish Amino Acid · “Remove it slowly and plant behind it, rather than clearing it all at once.”
- 47:06 Office Hours Ep. 58 (Nov 2022) — Jadam Sulfur for Disease, Flea Beetles, Seed Soak Solution · “Stop tilling, mulch with rice straw, fallen leaves, or wood chips, and apply IMO4 to rebuild a diverse, balanced soil microbiome.”
- p. 42 KNF Demystified · “The key to growing in rock is to begin by building upward.”
- p. 16 KNF Demystified · “When you add mulch, add microorganisms to avoid the carbon nitrogen depletion.”
- p. 12 KNF Demystified · “Keeping the soils covered is paramount, so only remove weeds when they can be replaced by beneficial plants.”
