starting a pesticide discussion

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likespaphs

some call me brian
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hi folks. it is not my intention to start a thread terribly technical about pesticides but i would like to make a few points to help keep people, pets and the environment safer while using pesticides as well as to bring up some important points about using pesticides.
this is not going to be a full list of all the precautions nor is it intended to be the only source of information for people.
if you think i'm saying something that's not true or if you have questions, please ask them or say something. i may make have made a mistake or been misinformed somewhere. as this is meant to help educate people, please ask questions. if i don't know the answer, hopefully someone else will. the only dumb questions are ones that aren't asked.

1. pesticides are meant to kill. as such, it is important that people take appropriate precautions while applying pesticides. this includes using the appropriate personal protective equipment, also called PPE (these are stated on the label), following the label directions as it is considered a violation of federal law not to, not standing downwind from the spray, making sure if you apply pesticides outside that it isn't going to rain before the pesticide dries, making sure no one nor nothing (pets or wild animals, insects, bees, etc) is around and will get the spray on them due to wind or overspray (overspray means when you are trying to spray one plant and due to either the pressure at which the pesticide is applied, it goes beyond where you are intending it to go and it inadvertently comes into contact with something you don't want to spray), and that the pesticide is appropriate for the crop (i.e. that you don't spray a pesticide meant for ornamentals on food crops). the label should also state the Re-Entry Interval or REI. this is the time after which it is safe to be around the plant(s) without wearing PPE. some pesticides have a very long residual life on the plant and will require special precautions for quite a long time (i know one that requires long sleeves, long pants and gloves when handling the plants for a month after application).

2. correctly identify your pest. if you don't know what it is, it is impossible to find an appropriate pesticide. there are lots of resources available online to help find out what the pest is. you can always take a photo and post it here and ask people or ask people in your local orchid society or plant store. if you bring an infested plant somewhere where plants are, it is appropriate to entirely enclose the plant in a sealed bag to avoid infecting plants at the place where you are trying to get info.

3. when you use pesticides it is imperative to rotate pesticides with different modes of actions. following are two links to a chart with pesticides listed by mode of action. the mode of action is the way the pesticide kills the pest. no pesticide kills 100% of the population to which it's applied. if you constantly use the same pesticide, eventually, the population which springs from the insects not killed by the pesticide will be entirely resistant to the pesticide. pesticide labels don't talk about avoiding resistance, they talk about delaying resistance as insects will most likely develop a resistance to any pesticide, some very quickly (i.e. after one spray of the pesticide), others, it takes a very long time. mites are notorious for developing resistance very quickly. http://www.chattanoogarose.org/MOA Entire Paper.htm
here's a pdf: Dr Ray Cloyd's mode of action chart

4. use the appropriate pesticide for the appropriate pest. pesticides aren't labeled for all pests and some pesticides have no effect on some pests. make sure the pesticide you are using is labeled for the pest or pests you want to kill.

5. apply the pesticide at the appropriate time. this kinda fits into following the label directions but isn't always explicitly stated. do not spray in the middle of the day as the droplets can act as little magnifying glasses and burn the plant.

6. available pesticides differ by state. some states allow some pesticides while others don't. check to make sure what you are using is legal to use in your state.

7. store your pesticides in an appropriate place. they need be inaccessible to pets, small children, as well as others who might misuse them.

8. also related to following label directions is making sure that you don't contaminate things. this includes ponds, groundwater, plants which are food sources for native insects and animals and other things. this can often come from incorrect spraying or improper disposal.

9. spray the pesticide at the appropriate time. some pesticides are only effective on some stages of insects (i.e. insect growth regulators that act as juvenile hormone mimics often have no effect on adults). this will be listed on the label.

10. follow the label instructions about the appropriate interval to wait until a respray. this kinda is influenced by the rotation issue. some pesticides suggest spraying again after a set interval. some say that you must use one or sometimes two different pesticides with different modes of action before a reapplication of the initial pesticide. this is to delay resistance....

okay. that's all i can think of right now.
feedback is appreciated....
 
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Really useful information, Brian.

I'd be curious to hear what is in our members "repetoire's" for pest management. I try not to use much more than alcohol and have been lucky to never have experienced a really awful outbreak of scale or mealies. The only issue I've had has been with thrips, and that issue has long since been resolved (though it wasn't easy!)
 
I'd meant to post on this thread but forgot. That list probably hits the same things as I try to cover. I'm of the camp that correct and safe use of chemicals needs to be said as often as possible.
 
Great info!

On top of pesticides, which I use rather sparingly, ie at the furthest extent of the application interval, and I try to rotate. Since our gh got running late fall, pests have been of little concern, although there was some scale from the plant boarders.

I also try natural "pesticides" such as carniverous plants, marigolds which are known to repel aphids and thrips, and we will also be introducing praying mantis, if available, this summer. Lady bugs can also be introduced to fight aphids and thrips, although once the food is gone, the bugs die. Make sure if using insects, that there is a way for them to get out when the food is gone.

Just my thoughts and experiences. I'm sure many people will laugh at me, but I have to say that I just adore mantis insects, so they are always welcome.
 
there are lots of great beneficial insects available. check out greenmethods.com.
personally, i don't think that preying mantis are good predators for greenhouses. they're very opportunistic and don't go after a lot of the little pest insects. ladybugs are okay but very flighty. there are many specialized bugs out there. i've got a parasitic wasp taking out my aphids as i type. here's a link to a youtube video...
 
When I managed to stop by the Cloud Forest Conservatory in Toronto, the volunteer(?) keeper was releasing beneficial insects. The greenhouse is above a garage in the city and people go there to eat lunch during the winter. wicked cool (substitute your fave adj here) public (indoor) park.


It's a small place above the "P" (click pic for a few more photos)


 

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