Identifying Invasive Tree-of-Heaven versus Native Sumac

tree-of-heaven versus sumacSo today I looked up from my Cutting Garden and realized that I had a tree-of-heaven (Ailanthus altissima) in the yard.  Despite the lovely name, this isn’t a good thing.  It’s an invasive—extremely invasive and vigorous, both.  I’m still getting to know all the plants here in Maryland, but this discovery annoyed me to no end.  I went after it with loppers, knowing this is only a temporary solution.  I’m going to have to cut it lower and paint the stump with brush killer, since pulling out the root is simply not realistic based on the location and the resources I have at hand.  My little lawn tractor is far to wimpy to take care of that, and I can’t take a four-wheel drive vehicle across my septic field to pull it out, and there is no way I could dig it out in less than twenty hours of work (quite literally—I’ve seen the root systems on those suckers).  And given its size, it will resprout again (this is the first time I’ve know what it was as I was trying to kill it but not the first time I’ve tried to kill it).

Tree-of-heaven is a bit tricky to identify because it look a great deal like sumac.  In fact, after knocking it back (again), I charged toward another plant before realizing that it was one of the native sumacs!  Most of the articles about telling the difference between the two focuses on the flower and fruit, which does make it super easy, but what about the 95% of the time, when you don’t have either to make an ID?

Well, there are two things that make the tree of heaven really stand out!  The first is that the bottom part of the otherwise smooth-edged leaves of the tree of heaven have deep notches in them at the base (on the right in the photo), while sumac has fine teeth all the way down (on the left).  The second is that tree of heaven smells like spoiled peanut butter when the leaves are damaged.  Very odd, but the description is totally apt.  (How would one know what spoiled peanut butter would even smell like?  Does peanut butter even spoil normally?)  Most people find it revolting.  To me, it’s mildly noxious.  This is odd because I have near superhuman smelling abilities, according to my friends, but maybe as the mother of a teenager, I’ve just mentally moved the goalposts for bad smells.

I also noticed that the twigs of tree-of-heaven are really thick compared to sumac and the new growth is more fleshy and herbaceous than woody, and the stems are reddish, but most oddly, at the tips of the new fronds, where the leaves haven’t fully emerged, it looks kind of like a closed up fan—a very different growth pattern than I’ve ever seen in a native tree.

Tree-of-heaven grows extremely fast, and the flowers of the male smell so bad it’s also called the stink-tree.  Part of me quietly wants to defend some invasives like the mimosa or, when I’m not cursing it and removing it from my flower beds, even Japanese honeysuckle, but there is truly nothing about the tree of heaven that is heavenly except its name.  If you see on your property, kill it!  You are not a corn farmer, so I don’t routinely recommend routine, heavy use of Round-up, but in this case, it’s your best bet—unless you’re able to pull the stump yourself.

On to other topics!  Today, I watered the Drive Beds, as I knew I’d have to.  I didn’t want to lose my astilbe.  (Really, they tend just to go dormant early if they don’t have enough water, but it will knock them back for the next year, which I hate, and they can eventually decline when this happens too much, like bleeding hearts.)  I watered, with Daniel’s help, while I called spelling for Amelia, so all was not lost, time-wise!  The foxglove got a good dose of water, too, which meant that the ferns and the hosta got some, too, along with the lilies.  Most people think that ferns are all moisture loving plants, but that’s not true.  Some do demand quite high levels of moisture, but ostrich fern, for instance, is firmly mesic, meaning it is perfectly happy with moderate levels of moisture.  It thrives not in the swampy bottomlands but on steep, shady forest slopes.

I also watered the sad side of the Street Garden again.  It’s already perked up a lot.  The viburnum looked a little sad, too, so I watered them.  Stupid me—I planted the first of the viburnum years ago, when I first moved in, and remembered only that it was a “snowball viburnum.” The type I bought had snowballs in midspring followed by exceptionally elegant foliage with a horizontal, structural appearance.  So I ordered a much more “snowball viburnum,” not knowing that there are at least three, maybe more, different “snowball viburnums.”  The ones I got instead have a delicious smell and much larger, hydrangea-sized blooms, which is good.  They also sporadically rebloom, with just a couple of blooms here and there until frost.  The bad is that their foliage is not even vaguely elegant.  In fact, right now, it’s almost heartbreakingly scraggly.  I hate to say it, but if they don’t look better in a few years, I’ll probably rip them out.  No front plant will be tolerated that only looks decent for a month of the year!

The basin water feature in the Children’s Garden is still keeping Daniel’s attention.  But its main attraction for Daniel is to hunt down frogs and toads from around the yard to put in it.  I limit the amount of time he tortures any given amphibian, though they usually stage a quick escape.

We have absurd amounts of both frogs and toads, though mostly the toads are out during the day.  I don’t even know all the varieties in my yard!  There are a large number of species, and they are just too similar to tell apart.  We stir them up constantly in the yard, much to the children’s delight.  I worry about stepping on them after dark.  At times they are too brave.

I also got my native Hibiscus moscheutos in the ground.  This one is a spectacular burgundy-leaved cultivar with white and pink saucer-like flowers. As I was going to the back yard, I found this waiting for me: skull in the yard

Yes, that is a skull in the grass!  It’s been lurking in the neighbors’ clumping bamboo since October, and somehow, it ended up on my side of the fence!  I pitched it back over.  Maybe one of the kids will think it’s chancing them.

My soil here is pure clay just an inch down—bright red, brick-building clay.  I’m not worried.  All you have to do is plant a few things tough enough to take the conditions, keep tossing on mulch, and water when it’s really dry, and eventually it with be deliciously soft and fertile.  I did this in New Mexico caliche.  Want tough soil?  That’s tough soil.  When I planted my first beds, I had to put down a drip hose for an hour to soften the ground enough that a shovel didn’t bounce off.  Maryland clay is just delicious in comparison.  In fact, when I moved my rose, the soil around it was already teaming with new earthworms.  That’s the power of consistent water and a little bit of shade.  You don’t need to do amendments or anything else when you’re not planting vegetables or heavy-feeding annuals.  I don’t even fertilize the first year, as it can discourage root growth in return for more top growth—and in future years, won’t don’t fertilize much beyond more mulch for shrubs and even most perennials.  Just plant, mulch, water.  I even don’t make wide planting holes.  Despite the standard advice, there’s really no support for it in the research.  I just pull the plant out of the pot, slash any girdling roots, even if that means slicing off the bottom inch of the root ball, and plop it in—not too deep!  If you make the plant happy with the right amount of water and some mulch, it will do all the work.

And now look.  Because I said that, I’m going to kill my rose by transplanting twice in one season.  (Poor baby!)