Orthene is systemic insecticide. It should kill the adults.
I would spray the plants if they are dry. But if you live in areas where it gets hot during the day, the old rule is to spray early in the morning (to prevent any potential burning).

Thanks Toyo! Another question, how long after it is sprayed on the plant is it safe to handle the plants with bare hands (pruning & general maintenance)? Also, will the orothene stay on the surface of the leaf long after it has dried? I water my plants by hand (as I live in a condo) every 7 days this time of the year, should I worry about wearing gloves the following week after I have applied the spray?

-Ray-

Hey Ray -
Since I remember when you were advised to eat apples treated with ?alar?, eat fruit sprayed with Malathion right after treatment, etc., I always err on the side of caution - get a couple of boxes of disposable latex gloves (200 for about $8 at Sam's) and use them every time you do anything!
If you get a buffer and adjust the pH of your water to about 5-5.5, the effective life of the treatment goes from 30 minutes or so to about 10 days - worth doing. I think the plants should be safe to handle once the spray has dried. If you have cats or birds that sample your plants, don't use a systemic.
The adults will eventually die, but I use an old toothbrush (sterilized between plants) on heavy infestations. The immediate spray is only effective on the crawler stage.
Scale can be a persistent problem, especially in winter when it's harder to treat things. Keep after it for about 3 treatments at 7-10 day intervals.
Regards - Nancy

Cool, thanks Nancy! I will get a test kit to see what my pH is & do some reading to see the best way of adjusting it. Thank you again!

-Ray-

As Nancy suggests, wear gloves. I not only spray, I also drench the medium with the Orthene to kill any eggs in the medium. Even though the Orthene is systemic, I do this once a week for three straight weeks.

Mmmmmm......
Well, I may be the only one who feels this way, but organophosphate pesticides like Orthene should be, IMHO, avoided at all costs.

Its much safer and just as effective to treat your plants with a horticultural oil spray, like Neem Oil, as it is to use a systemic pesticide. It achieves the same results, with the same every 7 day treatment schedule, and has the added advantage of being non-toxic and also being antifungal.

If you read the package directions on Orthene, you will see that they advise you to wear gloves, full body clothing and a respirator to spray Orthene. This is because its TOXIC. Its also nasty if it contaminates groundwater and can cause deformities in wildlife. Since you live in South FL and are in all probability a year round outdoor grower, this is especially applicable to you.

You might want to conduct a little research on scale as well. There are many different types of hard shell and soft shell scale. Most (but not all) types should be hand removed in every case because they do not disengage and fall off after they die, the dead shell stays on the plant, often leading folks to believe that they still have an active infestation, so they keep treating plants that are actually pest free.

Also, almost all scale insects (as well as mealiebugs) have a "crawler" stage where the insect is mobile and looks nothing at all like the mature shelled immobile adult. You need to learn to recognize these juvenile stages so that you can pick up on an impending infestation a lot sooner (and therefore treat it a lot sooner)before they actually attach and start sucking the life out of your plants.

i had a very bad scale infestation on my citrus and after I picked off all the visible scales individually, i sprayed with solution of murphy's oil and bit of dish soap. I sprayed the plant itself and the soil every couple of days for few weeks and it is totally bug free now and very lush & green. I imagine that this would probably work for an orchid too.
sue

Your best bet for orchids is to start using worm tea.It will take care of the scale and other problems.Orchids love worm tea.

Ray,
Be sure you use the water dispersable Orthene granules, not the liquid concentrate. The liquid is petroleum based and can harm the soft tissue. Be sure to wear a pesticide rated respirator and clothes covering all exposed skin when you spray. I hate to make it sound like this stuff is toxic, but it is. It is a great tool for reducing pest populations when harming beneficials is not a concern but make sure you do it safely. After spraying, do not enter the greenhouse for 24 hours. It will stink for days afterwards but the label has a 24hr REI, (restricted entry interval), after 24 hours it is safe to enter and handle the plants. As said before, apply 3 applications about a week apart. If you use this on any kind of a regular schedule be sure to switch the kinds of insecticides you use to prevent the population from forming a resistence to one kind. Orthene has been overused a lot and many pests have developed this resistence.

Travis

Thanks everybody for your terrific feedback! After going thru with my treatment this morning (before reading the new posts) I think I have determined that I want to try something different like neem oil or another non-toxic alternative. I dawned the full body clothing, goggles, mask & gloves. I sprayed down the plant & the medium over a large plastic container that caught the run off (now I need to figure out what to do with the run off, I don't want to dump it onto the ground... thatÂs the reason I had the plastic bin to start with! So anyways... I was thinking about using a bucket of insecticidal soap & dunk the pots into the bucket to take care of the little bugs still in the medium. Does anyone have a good recipe for mixing dawn dish soap? How much dish soap per gallon of water? Thanks again for all the great response!!

-Ray-

Ught oh... Travis, I am using the liquid Ortho product which has the primary ingredient being Acephate (IÂm not sure about that spelling). Is this also oil based? If so, I will have to get rid of it! Now with what you said about the oil based Orothene causing damage to the soft tissue, will another oil product like Neem or other horticultural oils also cause soft tissue damage? I am extremely inexperienced when it comes to pesticides as I have never had any plants that I really REALLY wanted to keep pest & disease free. Thanks!

-Ray-

I have used solution of 1/2 teaspoon pure neem oil, 1/4 teaspoon liquid dish soap in 1 liter of warm water and sprayed all my orchids and other plants as a preventative many times and have not seem any adverse effect on new growth or old growth. I do avoid spraying the flowers themselves. the plants, after the spraying, look green, and shiny and clean. some people do not like the smell of neem oil but i am ok with the smell - the smell goes away once it is dry. I find using pure neem oil and making the solution as needed is more effective than the pre-mixed commercial insecticidal soaps that I have used. others may have different experiences.
Sue

Ray,
I have never used the liquid Orthene so I can't speak of how bad the "adverse" effects could be. The ingredient you speak of, Acephate, is the active chemical ingredient that actually kills the bugs. The bad part of the liquid version is in the other ingredients. I have been told by several old, knowledgeable growers that the liquid is petroleum based and bad for soft tissue. Not sure exactly what they meant by "soft tissue" but it was enough to get me to buy the granules. I almost suspect that because these growers were older that they were speaking of a liquid version manufactured in the 80's, perhaps new acephate formulations have addressed this problem. Here is a link to the kind I use.

Here is a link that might be useful: Orthene

Sue, thanks for the recipe, sounds delicious! One question, I took a ride to home depot today on my lunch break looking for Neem oil, no luck! I saw a rose product that had neem in it, but no pure neem oil. Is it under another brand name? Or is this something that I will have to get from a grower or supplier like CharleyÂs?

Daylia Guy, Thanks for the link, I am checking it out right now! I had an orchid society meeting tonight & had a chance to talk with a couple long time growers that said Acaphate based systemics are good, but it needs a higher concentration of it. The product I am using only has a 4% concentration. I think I am going to try the neem oil recipe that Sue provided & just cover my flowers when I spray it. Thanks everyone!!!

-Ray-

I don't think I have ever seen pure neem anywhere other than horticultural and orchid supply places. I usually get mine on line...I can't remember where at present, Charley's or some other orchid supply place probably.

One thing about using neem, make small doses. I'm pretty sure that it loses efficacy the longer it sits...if I remember correctly...and probably I'm not!

I was told even after killing the scale, you should scrape off the bugs as the eggs are underneath and will survive and hatch. Also, the mouth parts are in the leaf and could cause a bacterial infection. You still should scrape the dead insects off.

Jane, you are right about that. The only purpose of the adult scale is #1 to suck sap out of your plant and #2 to produce eggs protected under the shell.

Neem Oil is widely available here in Florida. They have it at Home Depot, Lowes, Target, Walmart, K Mart...also the local independent nurseries carry it many times.

YOu can use the dormant horticultural oil ('light' oil) with the same effect. Both smother the insects AND THE EGGS as soon as they dry. Neem has the added benefit, though, of killing any sooty mold left behind growing in the honeydew secretions left by the insects, in one application.

hello, Ray, I got my neem oil at an orchid meeting. I think that Michigoose is right about getting it online, etc. I see that you live in South Florida: I guess you can check out the places mentionned by bihai. good luck - I really like using neem oil.
sue

Thanks Sue, Jane, Bahai, & everyone else for all of the information & experiences you have shared with me! I have learned a lot! I'm going to get some neem oil tomorrow & do a treatment Saturday & go to work with my old tooth brushes (I knew I was keeping them around for something!). Then I am going to pick up some lady bugs from a local nursery & keep them on the balcony! See you all in the other threads!

-Ray-