This week the multi-layered editors at the NDN had their way with my column. In the interest of full disclosure then, here's the original text. As usual you can click on the PDF at the left to download the version as it appeared in the paper. And the paper has my column online, too., although it's the sullied version…
I started looking into Black Olive ‘Shady Lady’ pavement staining because I needed to complete a glossary entry in my book. Then, a longtime Pelican Marsh client witnessed heavy staining and much leaf drop from Shady Lady earlier this year.
Many residents said: “We can't take it! Cut them down!”
It's easy to see the frustration.
The lovely and excellent Black Olive is popular for many reasons. It is one of three major street trees in southern Florida (the other two being Live Oak and Mahogany), as I mentioned last month. Black Olive is a very clean, desirable tropical tree with a lovely fine texture. Leaf litter is easy to handle, and the tree is essentially disease-free–with two major exceptions.
The smaller and most popular ‘Shady Lady’ variety reaches about 35x35 when mature. The much larger Black Olive, without the varietal name, is often called ‘the species’ in conversation. Black Olive is adorably called ‘Oxhorn Bucida’ by Doug Caldwell of the Extension Office. Those wacky scientists!
Oh. And this: Shady Lady does not stain pavement.
“But! But! I can prove it! I have stains!”
Well, of course you do.
And it’s under the Shady Lady tree, you say? Sure it is. But guess what? In the Green World, two plus two equals five.
Let me explain.
Florida attracts snakes, bugs, trees, insects, and Canadians. And among these invaders are two critters of special interest, both eager to please, both prone to over-tip.
First up: the Obnoxious Bungee Caterpillar (OBC), gleefully hanging from host trees on a silk-like webbing, intent on a chance purchase and sometimes landing on the face of an innocent passerby. This is irritating.
The favorite tree of the OBC? Yep. Shady Lady.
Before introducing critter number two, a bit about…well, number two.
The OBC (actually Characoma nilotica) appears sporadically in the late spring or early summer. The caterpillar prefers twigs that are less than a pencil-width (the new growth). This activity isn’t so objectionable. There is some defoliation, and in some years a many leaves are lost, but they come back. It’s not the eating that’s the problem.
It’s this: All critters, including the daintiest reader, follow an inviolable Rule of Nature: what goes in, must come out. OBC poops like crazy.
In fact, the poop of the OBC is the cause of pavement staining. And now we learn that scientists have a Humor Department, from which we learn that caterpillar poop is properly termed ‘frass’.
Caterpillar frass stains paving. Shady Lady does not stain paving. Clear? Your Design Pundit would not mislead you.
And here’s the second invasive critter: an enchanting, small and mite that induces the tree to form a ‘gall’, a string-like structures which the mite uses for shelter and food. Pretty amazing, really.
Doug Caldwell has been able to associate these ‘string galls’ (4-6” long) that sometimes appear on Shady Lady trees with an additional OCB lifecycle.
Twice as much poop.
Do not think that this entire story is entirely understood. It is not. We know neither where the caterpillar lays eggs nor where the pupae live, amongst other unknown details. The known story is largely the result of original scientific research by Dr. Caldwell, who has a very useful movie on YouTube that describes the issue (http://bit.ly/QV9pSd).
For many, this isn’t much of an issue, especially if there is no paving about. The accelerated leaf drop that we see on infected trees is annoying and, yes, occasionally a tree is nearly defoliated. But new leaves quickly appear and in these cases I advise clients to simply be patient.
Other cases are more critical, especially where Shady Lady is used as a residential street tree adjacent to expensive special paving or irritable people.
However, it appears that there is a prophylactic prevention for the OCB and the mite. More on this in the coming weeks.
Thanks for the email on the cat story of two weeks ago. It’s very much appreciated!
Is there anything better than a purring kitty in your lap? Nope.
Suzie and I are caring for an adorable solid black kitten named Lakshmi (this is the Hindu goddess of wealth and prosperity), and while we love all of the kitties, we need to re-home her because we just have too many (trust me, eight is enough). Lakshmi is very healthy and neutered and loves people. And, yes, you would need to pass my personal security check before I would release her!
Finally, it’s the dog-days of summer, and my email has slowed to a trickle. Feel free, folks, to email me about–well, anything.
One day I will write about some of the email that I receive (protecting the innocent, of course). Many of you have straightforward plant problems. But I get a surprising number of personal questions, too: one lady wanted to know about her wandering husband, and anther teenager had angst over her prom dress.
It is possible that I have missed my calling.