Home & Garden Columns

Green Neighbors: Another Handsome Hazard: Chinese Tallow Tree

By Ron Sullivan
Tuesday October 23, 2007

Chinese tallow tree, Triadica sebifera, Sapium sebiferum or Croton sebiferum, is pretty, tough, and dons beautiful leaf colors in autumn. The small rounded kite-shaped leaves have a gentle green color before that, and dance engagingly in the breeze flashing their soft gray undersides, a little like aspen leaves.  

It really is Chinese—well, East Asian in general, including Japan—and it really does supply a sort of tallow. (It really is a tree, too, in case you were wondering.) The tallow is a waxy coating on the seeds. These, somewhat perversely, stay on the tree when its fruit, a capsule that starts out green, matures to black, and then falls away. The seeds’ coatings give them a subtle translucence that looks nifty in the sunshine; they’re round and tend to hang in threes, making some of us (OK, also perversely) think about teeny forest-elven pawnshops.  

Have I overdosed on Terry Pratchett again? 

The “tallow” covering the seeds is actually useful too. It’s gathered, not by leprechauns with tiny little vegetable peelers, but by ordinary humans who throw a load of seeds into a vat of hot water, wait for the wax to melt off the seeds and rise to the top, and then skimming it off.  

The stuff makes decent candles (with beeswax added) and soap. I’ve seen it proposed as a source for biodiesel. I’ve heard that it can be used as cooking oil, and I’ve heard that it’s a strong purgative. I’ve heard similar things about red palm oil; maybe it’s a matter of quantity or of individual susceptibilities. Either way, don’t say I didn’t warn you. 

Some birds like the seeds, and apparently whatever the intestinally controversial element for us is, it doesn’t bother them. In particular, birds that eat bugs—woodpeckers, for example—like the fatty coating; hardly surprising if you’ve seen them go for suet cakes. They eat the whole seed and, at whatever speed and interval, eventually excrete the working part along with a nice dose of guano fertilizer. And therein lies the rub. 

How rough a rub? Here’s a hint: In Florida, it’s illegal to introduce, release, move, or possess a tallow tree without a special permit. It’s on the Noxious Weed List there and in Texas, Georgia, Puerto Rico, Louisiana, and Mississippi, and it’s being strongly proposed for addition to the official list here in California.  

This, as such steps often are, is a bit of barn-door locking as the horse disappears over the horizon. Tallow tree is so entrenched in Florida that many people think it’s a native; it was offered by nurseries as “Florida aspen.” (It’s also “popcorn tree” because of the alleged resemblance of those white berries. Somebody’s evidently been making some nasty popcorn in the Southeast.)  

You can hear or read complaints about tallow tree from all those other states, too. You can also see it defended. No surprise, since individually it’s really charming, and since people seem to confuse garden-invasive with wildland-invasive or not even to know the latter category exists or matters. 

This tree is a perfect exemplar of the myopia problem. If its seeds fall into your garden and sprout a zillion little seedlings, you know it’s garden-invasive. It’s a problem in flowerbeds; less so, in lawns and tame meadows, because seedlings are easily controlled by mowing. So, if you see only your own garden and maybe the neighbors’ (That tacky old juniper hedge! That obsessive brickwork!) you won’t see any danger in a tallow tree; just that neat shape, those pretty “berries,” that gorgeous autumn color.  

When the flock of songbirds has had its picturesque fill and flown off, though, they’re going to be flying over and hanging out in places that people don’t mow, where the hundreds of myriads of other Earthlings must live and raise their offspring and eat and sleep.  

The tree that feeds those songbirds won’t necessarily have anything the other animals and plants can use—no oak leaves or acorns for the bugs that live on them, therefore nothing for the local species that live on those bugs, therefore no pollinators for the flowers that need something with those bugs’ particular habits ... 

No acorns for the acorn woodpeckers, who might relish a tallowseed snack but can’t store it against the needs of next spring’s breeding season. No oakleaf mulch for the native understory plants either. Tallowtree leaves, in fact, might be a bit toxic to other plants as well as animals. 

And tallow tree, like so many other invasives, can make a monoculture thicket that goes on for yards, and another like it just downstream, and in five years yet another downstream from that. For some species, that’s no better than paving. The catch is that we don’t know which species those will be, or who else depends on them.  

Dang. And I really like tallow tree; it looks good and feels pleasant to work on. Too bad.  

 

 

Photograph by Ron Sullivan  

Chinese tallow trees, these in the , Oakland hills, in fall color right now.  

 

Ron Sullivan is a former professional gardener and arborist. Her “Green Neighbors” column appears every other Tuesday in the Berkeley Daily Planet, alternating with Joe Eaton’s “Wild Neighbors” column. Her “Garden Variety” column appears every Friday in the Planet’s East Bay Home & Real Estate section.