Buttonwood with Scale

I have a shohin buttonwood (Conocarpus) still in the nursery pot, under lights for the winter. It s healthy, but has a light attack of scale insects. I do not believe in those old wives' home remedies. Which insecticides available in NY State are both effective and safe for buttonwood? What about Imidacloprid?
Iris

Hi Iris,
I have a Buttonwood also and it gets scale now and then. I have used Immunox Plus by Spectracide with great success. I use this on lots of tropicals with no ill effects. Do not use it if you have cats as it is highly toxic to then when wet.
It is sold at Home Depot or on the net.
Do not use Malathion it will kill Buttonwood.
Insecticidal soap works too.
Regards,
Geof

Iris,
I have used the run off from rinsing Diatomaceous(Sp?) Earth to treat scale on a palm. The micro abrasive qualities cut through the outer shell and they dry out. In a spray bottle it works on mild infestation and for more severe infestation will at least control it until springtime when you can use most severe pesticides outdoors. I also manually remove them from Umbrella plants by scraping gently with a plastic knife or spoon. Just an idea. Good luck

Todd

Yes. If it is just a minor infestation, I was going to suggest manual removal.

As far as I know, pyrethrins do no damage to any plant.

I was looking through my armamentarium & found an unopened bottle of acephate (Isotox). I think I have used it around buttonwoods before. Some of you may not approve of systemics, but I don't believe it has ever damaged a plant when used correctly. I lost several trees when I tried using one of those new "environmentally safe" concoctions.
I believe acephate is off the market in NY State. That's why they have all those bedbugs. The big cheese right now is Imidacloprid. Beware of it, even if you can spell & pronounce it. Unlike acephate, it has no effect on spider mites. In fact, come to find out, because it kills a parasitic wasp, it greatly encourages the proliferation of spider mites.
I'll let you know what effect acephate has on my buttonwood.
Iris

It has been several days, the scale are gone, & there is no sign of phytotoxicity from the Isotox. I will follow the standard procedure for scale (also mites & mealy bugs), & spray twice more about a week apart. With these hard to kill insects, the eggs are immune (hidden under the hard-shelled adult), so you have to kill them right after they hatch.
The important limitation with systemics is that you are not supposed to use them indoors. If I have to use them in the winter, I spray the plants in the plant room or on the sunporch, then quickly close the door & nobody goes in there for two hours.
Iris

Hi Iris,

I am a student of Mary Madison, a.k.a. The Buttonwood Queen, and I would suggest manual removal of the scale. As for the systemic... I use Bayer's granual systemic on my buttonwoods, and I haven't had any issues. Good Luck.

Mike Lebanik

Michael Lebanik wrote: I would suggest manual removal of the scale. As for the systemic... I use Bayer's granual systemic on my buttonwoods, and I haven't had any issues.
Mike Lebanik

These are tiny & fuzzy, more like mealy bugs. Hard to remove by hand, & not a reliable method.
Bayer's is Imidacloprid. I have already mentioned its big drawback. It encourages spider mites. The buttonwood seems to be doing fine.
Iris