I hadn't considered rotating the chemicals I'm using to avoid resistance. Thanks for the tip! I'll definitely swap between Malathion & Bayer.

I just looked at Safari on google and my eyes bugged out when I saw the price. :shock:

Malathion and most insect sprays are not effective against scale.

Many types of scale lay their eggs in the potting medium around the roots. This is why it came back stronger than before you sprayed.

If you kill the scale you still will have the brown scale shell on the leaves. Scrape one with your fingernail and crush it. If it is green inside it is alive. If it is dead it is brown.

I use Vermi-liquid (worm secretions often called worm tea) once a month on all my orchids. I rarely see scale.

The liquid has a chemical called ceitanese, which does nothing except dissolve ceitain. It is organic and harmless to us, children and pets but fatal to insects whose skeleton is ceitain.

I spray mostly for the microbal effect of the Vermi-liquid but the elimination of many pest is a good bonus. It is extremely effective against spider mites.

Heh, check out the price for an 8 oz bottle of Judo miticide:
Judo Miticide, 8 oz. - Insecticides | Greenhouse Megastore

$445 an 8 oz bottle and they only claim it works against mites and white flies.

The biology of scale is considerably different. I would not spend that much unless they were guaranteeing results against scale.

:shock::shock::shock::shock: that made my eyes bug out ..

The price itself is not that extreme. There are a lot of others int he same price range.

The best anti-fungicide is Heritage at $600 a pound, but you really need to have enough plants in danger to spend that much.

Another thing is people often recommend these chemicals and do not realize they are illegal to sell for home use and very dangerous to use.

They often require fully covered disposable clothing covering the whole body, hands head eyes etc. and a high efficiency gas mask

Nothing we were discussing in this thread requires such extreme precautions.

For example you might want to try reading a label for imidacloprid:
http://www.domyownpestcontrol.com/ms...n_2L_label.pdf

Applicators and other handlers must wear:
• Shirt and pants
• Gloves
• Shoes plus socks


It was not being recommended for scale but just being offered as an example of an expensive insecticide.

Malathion is listed for scale and spider mite and is an organophosphate with low toxicity to humans and animals. It is even used in low amounts in ointment for such things as scabies! That being said, scale are very tough to eradicate and it needs to be used repeatedly or rotated with something else. I still think a systemic is a good way to go.

most of the stuff you use can be absorbed by practically all routes including the gastrointestinal tract, skin, mucous membranes, and lungs. You should wear protective gear with any insecticides you apply for general safe practices and to limit long term exposure to these items. You can become sensitized to them after repeated exposure and develop your own physiological or temperamental peculiarity.

Wow! I can't believe the prices on pesticides in such a small quantity. It makes sense to those who have a large quantity. Here I was debating whether I wanted to spend another $15 on something else.

That's a good tip about wearing protective gear. When I was doing the Malathion spray outside, there was a slight breeze and I accidentally inhaled some of it. I was coughing up a storm for a good few minutes.