Irritating and time consuming pests (and treatment with Perimicarb)
(Message posted to the World Wide Butterfly Breeding Forum)
From: Nigel Venters Sent: Monday, November 19, 2012 To: firstname.lastname@example.org Subject: Irritating and time consuming pests
Apologies as I have not posted much lately as I have been busy with workshops and my breeding.
However, sometimes it is the small things in life which irritate us the most. And here I mean Aphids! Especially when we breeders produce host-plants under cover, and there are few natural enemies to keep them in check. Aphids can devastate a host-plant, and although, I do like to just squish them as soon as they appear, you can never get them all, and they start off again.
Now I am usually totally against using any sort of pesticide in my set-up, and only when faced with a really devastating outbreak of pests, I begrudgingly will use an effective contact spray like Malathion. Malathion being a contact killer is easy to wash off the host-plant with a water spray, and is safe only 24 hours later. (I wait 48 hours to be safe!)
I would never advocate the use of systemic pest killers, as they remain effective within the plant for some time after application, as many breeders who have brought plants from a nursery have found out to their cost.
OK, many of you may have also heard that I use a SYSTEMIC greenfly killer, and the active chemical is Perimicarb. I have often said this is a very unusual pesticide as it is a dedicated greenfly killer. Yellow Milkweed Aphids, black or green on whatever plant you are growing are effectively killed by this chemical, but just as stated on the bottle, it does not affect bees, Lacwings etc. (or larvae!) It is a selective greenfly killer. I also mentioned that I have tested this on eggs and larvae of the butterfly species I breed, and found they remain totally unaffected, while all the Aphids die.
So I thought I would try and show you just how effective this chemical can be for you. So see the attached photo! All that is necessary is one spray to kill all the greenfly, but this experiment was set-up to REALLY test this chemical! I spayed the plant 5 times. And the outcome? No effect at all on any eggs or larvae, and the larvae developed normally, and then paired normally and laid eggs as normal.
Anyway, Aphids can be the most annoying pest, and if you can find this product, I really recommend it to you. If you use it, do stick to the instructions and mix it carefully to what is written in the instructions, and you can have a greenfly free life from now on!
Hope this is on interest!
I deliberately infected this Milkweed with Yellow aphids, then put gravid Monarchs to lay on it. I waited until there were both eggs and newly-hatched larvae, and for the Yellow Milkweed aphids to task hold and thrive.
I then sprayed this plant with Perimicarb, which killed the aphids but had no effect on the larvae.
One application of perimcarb is enough, but I sprayed this plant 5 times to test the tolerance of the larvae to Perimicarb. All these larvae progressed normally and produced healthy adults, which then reproduced normally.