Correct Orthene dosage

[oborchid]

I have Orthene Turf,Tree and Ornamental Spray 97, which contains Acephate(O,S-Dimethyl acetylphosphoramidothioate) 97.4%. I am a little confused after reading the label. I think the correct dosage is 2/3 tsp per gallon of water. Is this correct? And can it be used on slippers, oncidiums, and cattleyas?

[Jerry Delaney]

2/3 tsp/gallon is correct. Orthene soluble powder is labeled and safe for use on orchids including those in question. The soluble powder will not harm the plants or the flowers.

[cirillonb]

do you think there is an expiry date on Orthene WP? I found a can in the co-op that was dusty and grimy and not on their newfangled computer database. Price was good, however and probably negotiable. I am an Orthene junky after trying to grow azaleas in a high spider mite environment. Worked great. Also worked on all rose problems but molds and of course Japanese beetles.
Nick

[Jerry Delaney]

I am not aware of any expiration date associated with Orthene 97s or 97wsp but that doesn't mean there isn't one. They have always said for Orthene 95s, 97s, and 97wsp that the product was completely stable if stored at temps under 180 degrees F. I would imagine that unless this material went through a fire, it would be just fine. My memory is not so good but I seem to remember that Orthene was a part of the "Ortho" line and I believe owned by Chevron. I don't really remember when the product line was sold to Valent. I do know that in the mid 1990's the Orthene products were being packaged by a contract manufacturing company in Memphis Tenn. I don't think that the 97% product came out until late 80's or later (it had been 75% prior to that).
By the way Nick, just to make things more difficult, Valent sold the Orthene line to AMVAC in January of this year.