We officially have a new successful tropical invasive tree species to add to the list of woods that WORK for growing gourmet mushrooms on!

Oyster Mushrooms on Invasive Wood

Oyster Mushrooms on invasive wood

Octopus Tree (Schefflera actinophylla) is “without question, one of the worst weeds currently invading the wet forests of the Hawaiian Islands” and “the Division of Forestry and Wildlife of the Hawaiʻi Department of Land and Natural Resources has designated this species as one of Hawaiʻi’s Most Invasive Horticultural Plants”, according to PlantPono.org. As a result, people are constantly removing this tree in order to control its invasive spread. Its cut wood is therefore a waste stream that can be closed to successfully grow edible mushrooms on.

Thank you to everyone who attended our mushroom log inoculation workshops & participated in this wood species experiment with us. As a result, one of the smaller 2-inch diameter logs has already finished myceliating & has fruited a beautiful flush of gourmet, medicinal oyster mushrooms in only 6 months! The larger diameter bolts will need some more time to finish myceliating and will not likely fruit until next rainy season. However, if you took home a Schefflera bolt as a party favor from our workshop, be sure to keep a watchful eye for fruits, especially right now if you have a smaller diameter log.

We would like to thank everyone that came to our first few workshops & participated in a mass scientific experiment to find out which of our local invasive wood species would be best suited for growing gourmet & medicinal mushroom species here in the tropics. We’ve spent years researching & practicing mushroom cultivation & one thing that we’ve encountered over-and-over again is that the great majority of how-to information out there only describes how to grow mushrooms in cold, temperate climates. We’re going to change that starting right now.

We have many goals for our workshops: getting more locally-grown functional foods into the bellies of those around us, skilling-up our local community, & collectively honing our local mushroom cultivation skills to find out what local best practices are in our bioregion. While there have been many successful highs in this process, we would also like to share the lows so that we can help our community become better mushroom growers.

First the good news, the invasive silky oak (Grevillea robusta) logs that we inoculated with gourmet & medicinal mushroom spawn have been robustly fruiting mushrooms all rainy season long.*

shiitakes on Silky Oak

shiitakes on Silky Oak by Adam Hicks

Now for the not-so-good news, the hyper-invasive guava does not work for the traditional log-style of mushroom cultivation. The traditional drilled-hole bolt & standing totem methods require tree bark that is sturdy & robust, as this bark protects the mycelium that grows just underneath it from deadly sunlight, wind, & critters. Unfortunately, the bark of the guava tree is just way too thin & brittle & comes apart before the mycelium can finish running its life cycle to the mushroom fruiting stage.

guava bolt

Guava bolt by Helena Berg

In other good news though, the technique of layered, used cardboard fruited a second flush. This inoculated cardboard crate has now yielded a couple of pounds of mushrooms off of FREE discarded cardboard!


oyster mushrooms fruiting on cardboard

Oyster Mushrooms growing on cardboard

In our upcoming workshops, we will continue to work with multiple wood species so that we can learn & teach more about mushroom growing in the tropics. We will continue experimenting with new wood species while increasingly phasing in wood species that we know will fruit so that we can be confident that more mushrooms will be fruiting at the same time that we are doing our scientific experiments to improve our collective knowledge about mushroom growing in the tropics.

Hope to see you at our next workshop soon.

* Caution: wear a respirator when harvesting the silky oak (Grevillea robusta) wood as some folks are allergic to the inhaled sawdust. Luckily, the mushroom mycelium denatures any toxins in the wood through their natural decomposition process. All reports coming in are confirming that the mushrooms grown on this wood are very flavorful & are being eaten without any ill effect. Remember to always properly 100% identify & always thoroughly cook your mushrooms before eating so that you can benefit from all that they have to offer you.

As I look down where my red earth stained boots tread I see it! A rubbery, dark brown fungal growth emerging from the side of a twig no larger than the width of my index finger. I crouch down to the tree-shaded ground to have a closer look. Soft, velvety fuzz adorns the top of the emerging growth that looks nearly identical to the ear of a small, brown mammal. I pick up the twig and turn it slightly revealing the smooth underside of the mushroom. With a smile I glance towards the cloudy sky where I gaze upon the signature canopy leaves of the iconic tree whose nuts provided light to the people of this region for roughly a thousand years.

I close my eyes and extend my heart in all directions, connecting with all around me to share my intentions and to humbly request their permission for the harvest.

Five years earlier:

I raise a 16-pound iron digging stick straight up into the air, stab it down into the soil, and swirl it in a circle to create a conical cavity as Dr. Art Medeiros excitedly speaks of the interconnectedness of the species in this endangered forest he helped to revive. He carefully places a young native tree’s taproot into the narrow hole created by the digging stick and lovingly packs the soil back around it. I eagerly ask him about the cloud ear fungus I often see in forests during the cool, wet months and he excitedly talks about its important role in decomposition of fallen wood and how this species is a native mushroom to the Pacific islands.

Being native to the Pacific islands means that this fungus could have only arrived here by one of three ways: either by the winds, the wing of a bird, or by a wave. Did some mushroom spores get swept up and away in a storm system from a far away continent and amazingly land on fallen wood here? Did an exhausted golden plover, escaping the seasonal frigid cold of a temperate land, have touched down here with spores in its feathers? Could a mushroom – or its mycelium – have survived thousands of miles of open ocean waves on a log to land on these shores and upon maturity eject its spores here? I have seen cloud ear growing on a driftwood log sitting upon a windward beach. I think about all the cloud ear mushrooms I often see on fallen candlenut twigs and logs… could it have even first arrived here on a canoe centuries ago? All possibilities, I suppose.

Today, people are filled with the excitement of all that fungi offer to us and to the ecosystems upon which we have emerged, shape and rely on. Their excitement renews my passion for fungi as well as my passion for finding, propagating and caring for the native mushrooms here in these Pacific islands.