One of our favorite fall-flowering trees is the tropical-looking Schefflera delavayi. As a child, I was always enamored with schefflera on our family vacations to Florida, never dreaming it would be possible to grow these “tropicals” in our Raleigh garden. Fast forward 60 years, a number of “hardy” schefflera species in the Arailaceae family have entered the trade, but few have shown the combination of winter cold tolerance with summer heat tolerance. The star of the genus for the Southeastern US has certainly been the Southern China/Vietnam native, Schefflera delavayi. Below is our garden specimen this week, growing beside our office. In order to get viable seed, it needs a second clone, so Doug cuts a few branches from a specimen on the far end of the property, and puts it near this flowering specimen for cross pollination, which is performed by an array of different bees.
While pollination is fairly straight forward, Schefflera taxonomy is a literal train wreck. Of the 1600 taxa in the Arailaceae family, 882 species were in the genus Schefflera, until significant deconstructive changes were proposed in 2005. Of those 882, 300 species still have not been formally described. Where’s a taxonomist when you need one? The genus, Schefflera has long been what is known as a taxonomic dumping ground. In other words, it takes too much work to actually sort out members of the genus correctly, so newly published taxa are simply dumped into an existing genus that’s convenient. …in this case, Schefflera.
To understand this, we need to look back further in time. Prior to the late 1800s, there were many more genera in the Arailaceae family than there are today. In the late 1800s, the trend of taxonomic lumping was in favor, and there was a published proposal to lump all twelve of these different genera into Schefflera. From that point forward, the taxonomic dump was open for business. Fast forward 150 years, taxonomists are more open to rejecting the unwise lumping that took place earlier, and as such, began to look suspisciously at large genera, that were spread over such a wide native range. Using newer DNA tools, the genus slowly began to unravel.
In a 2005 paper, DNA tests showed that the genus Schefflera was strongly polyphyletic. Polyphyletic simply means that distant cousins are trying to mooch off a family’s good name, by showing up at family reunions. Once this was realized, the outsiders in then genus had to be booted out of the genus, Schefflera. Unfortunately, plant taxonomy is a bit like long electrical cords…it is much easier to tangle them than to subsequently untangle.
The first Schefflera named was the New Zealand native, Schefflera davidii, in 1775, so it, and it’s close relatives lay claim in perpetuity to the name, Schefflera. Other, less closely related outcasts have to be re-named, so the twelve previous genera that were ruled synonymous in the late 1800s are back in play. They chore now, is to use DNA to determine how those names should be applied, and to what species. In 2020, 317 species from Asia were formally evicted from the genus, Schefflera, and placed in the genus, Heptapleureum. More changes are afoot as the DNA work continues.
Such a beautiful plant, Schefflera delavayi., Ha, ha, “DNA tests showed that the genus Schefflera was strongly polyphyletic. Polyphyletic simply means that distant cousins are trying to mooch off a family’s good name, by showing up at family reunions. Once this was realized, the outsiders in their genus had to be booted out…”.
Haha, every family ‘tree’ has one ‘polyphyletic’ member or branch, they are usually the most interesting characters in the family. Haha, some families are in denial of their messy lineage and at one point every family member angered parents who then wanted to boot them from the genus.
Plants are more like people than most realize.
That said, I’ve tried Schefflera delavayi in our zone 8a garden near Raleigh NC and so far so good. I’m on my 2nd attempt with Schefflera taiwaniana; the 1st succumbed to acute heat stroke during a 100 degF draught; the 2nd one is in a container and ‘loving life’. This time they will be “over-summered’ indoors in an air conditioned dehumidified “ecosystem” found in our sunny breakfast area in front of French doors.
Are there other Schefflera/Heptapleureum species that have been identified as promising for the trade or interesting enough for JLBG to trial? I understand they respond well to grafting so someone with that expertise should be able to graft other species on to S. delavayi root stock if they are grown in such numbers, possibly by west coast nurseries. Then, god forbid, we will have ‘blended families’ to add to our diverse gardens. Haha, the end of civilized society!
Thanks!
Greg
So far, we’ve trialed 17 Schefflera (Heptapleureum) taxa and only S. delavayi has survived.