Ugh, bugs

[jkofferdahl]

In the many years I’ve grown orchids, I’ve come to fear two things more than any other problem that might affect my plants. Whenever a new grower sees an issue with an orchid their first concern is VIRUS! Viruses do happen and I suppose we’ll all encounter a viral plant at some point or another (and may never even realize it), it’s my experience that they’re pretty rare in small, personal collections (though in such a collection they could quickly decimate). The two things I most fear are mealybugs and scale. Both are capable of rapidly infecting an entire collection, and because they don’t necessarily do long-term damage to a plant we are forced into all-out warfare against these insects.

Today, as you may have guessed, I found scale on a plant, Phal. deliciosa. Finding it brings me to a question, or thought, which is that I’ve never quite been able to determine a “patient zero” with scale. Sure, I remember once, some years ago, receiving two Phals from a well-known grower with scale on them, but this was, in my experience, an exceptional instance. The Phal in question today has been, like the few other instances I’ve battled scale, in my collection for a long, long time – the source is not relevant because it’s been happily living among my other plants for about 2 years. How, then, did scale enter my house and get on this plant? The number of individual scaleybugs I removed by hand (well, Q-tip and alcohol) surprised me, as I’d not noticed ANY before today.

This, of course, led me to begin an investigation. I received four plants on Saturday, but these plants arrived too recently for the infected Phal to have picked it up from them. Naturally, then, they were the first plants I inspected (yet again – I ALWAYS inspect plants when they arrive – even from LOC or Peter!!). They are, of course, as clean as a plant from LOC (or Peter) always is. So I inspected other more recent arrivals, all of which are also clean. I should stop my narrative a second here to note that yes, when a new plant arrives I isolate it, regardless of the seller, and also thoroughly inspect it (I even use a magnifier lamp) to be sure it’s OK. Those newest plants I mentioned are still in isolation, despite knowing that they’re fine. Also, most recent arrivals are miniatures which grow not just in a different area but in an area in a different room of my house.

Anyway, I’ve spent a good two hours using a proverbial fine-toothed comb (OK, my vision is poor, but with a magnifier I can see just fine) inspecting all of the orchids in my kitchen grow window, where deliciosa lives. Nothing. I regularly treat the plants in the area with a dusting of diatomaceous earth, which, in over a year, has kept the area bug free. The ONLY plant on which I’ve been able to find scale is this one. Somehow, then, it has to be the patient zero – and hopefully will be the only patient! Naturally I’m not convinced, and expect to find scale elsewhere! However, I haven’t yet.

And that leads my thoughts in two directions. First, is scale something which could hitchhike on an insect and then get onto a plant? I’m not an entomologist (took a class in college), but have heard of such, though it doesn’t seem likely. Second, is scale an insect which could find a comfy place to basically hibernate for a year or more before deciding that conditions were right to come out? Have others experienced a seemingly untraceable infestation of scale?