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I'm trying to treat my azaleas for lace bugs without harming my honeybees. I'm especially concerned since it's not just wild bees. I've started a hive.

I've been looking into it and my local AG Extension website shows three chemicals I'm interested in. One is 'Acephate' which is a foliar spray that is systemic. I think the effects my last 1-3 weeks. The other two are 'Imidacloprid' and 'Dinotefuran'. The last two are either granular or a drench, but they're also systemic and are supposed to treat for an entire season.

I'd love to use one of the latter two, but I'm worried for my bees. A couple of my azaleas try to grow every year and end up damaged and poor looking. I'm almost positive it's lace bugs after doing some research this year. A lot of last years leaves are yellow and spotty and have dark spots like insects or insect poop on the underside.

I know the systemic poisons can be harmful to bees, because it can travel up and enter the pollen and nectar. However, I was hoping someone could tell me if it's harmful to them if applied after flowering has stopped. If they aren't flowering, then they won't have nectar and they bees won't ingest the poison.

I know, however, that azaleas start growing the following years flowers when the ones from this year drop. So, will they systemic poison applied after flowers drop this year, pollute the nectar for next years flowers?

Thanks for any help or info on this. I'd like to see my azaleas do well this year without harming my bees. I'm open to other suggestions on treating for them, but I'd like something that's fairly effective. I don't want to have to go out and coat every square inch of leaf surface with neem oil every too days. It would be ineffective, time consuming, and I'd probably miss a lot of the undersides of the leaves, leading to a reinfestation. Thanks for the help.

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Well, I wouldn't be using any of those, particularly not imidaproclid, and I don't keep bees - that substance has been or is about to be withdrawn in the EU for two to five years to see if it impacts on the bee population, because there is such conviction of its environmental impact on bees generally, never mind whether its sprayed on open flowers or a plant with no flowers. Acephate appears to be an organo phosphate, and I'm surprised you're still allowed to use those; all organo phosphates marketed for garden use were withdrawn in the UK and Europe at least three years ago. Organo phosphates cause neurological damage in humans in the long term at the very least, and once in the body (absorbed through skin or any other route), they never leave. Therefore, I see no reason to suppose the other one you mention will be any better, but then, after many years of gardening experience, I've become an absolute sceptic or, if you like, unbeliever when it comes to pharma companies declaring their products to be safe, or safe if used in a particular way. I'll admit its tempting to use these products, and certainly, many of the ones withdrawn over here are much missed, without suitable substitutes, but I'd rather not poison the environment nonetheless. I wonder whether you've tried a more organic route, such as neem oil or insecticidal soaps - more general info regarding lacebug control in the link below

http://www.gardeningknowhow.com/ornamental/shrubs/azalea/azalea-lace-bug.htm

  • Thanks for the reply Bamboo. I did see where you answered a similar post about the 'Imidacloprid'. I just didn't see anyone offer an alternative solution and it had been on the recommended list, so that's why I felt I was safe in asking the question. I haven't tried neem oil yet, because I don't know when to apply it and I know you have to cover all leaf surface, which I'm not confident I'll get. I'll check out the link when I'm not blocked at work. Thanks. – Dalton Apr 14 '16 at 19:42
  • Sorry to be so downbeat about chemicals, its the voice of experience! believe it or not, we're not even allowed Neem oil here... we just have to rely, mostly, on keeping plants as healthy as possible, though there are insecticides available which are effective for most things and not too damaging. the worst is the lack of fungicidal treatments, nearly all withdrawn, which is why I'm always mentioning milk remedies for blackspot and mildew. And they absolutely don't damage the environment, obviously... – Bamboo Apr 14 '16 at 20:09
  • Believe me, I really am anti-chemical. I just think there comes a time when you need the help to knock out a problem. If there is a more environmentally friendly way to do it that isn't outrageously more expensive, I'm all for it. – Dalton Apr 14 '16 at 20:14
  • Wow, Bamboo! They've banned NEEM? Why? Hey Dalton, if you use NEEM only use it at night. Some NEEM products say bee friendly and others say Not. Very effective but do not use it until night. It'll dry before any bees come in contact with it. It is very effective for all kinds of stuff...even making leaves more shiny. Unless it is prohibited this is the only pesticide I'll use and only when manual measures aren't working. And only at night. Whoa, Bamboo...I applaud the UK for being so careful with these pesticides! Why though? Has Neem properties I don't know about? – stormy Apr 15 '16 at 21:20
  • @stormy Not sure they've banned it, its just never been available - there are one or two horticultural oils for pest control, just not basic neem, unless you buy a bottle from the aromatherapy supplier. I notice amazon used to sell a garden version of Neem, but its no longer available, so maybe it has been withdrawn. – Bamboo Apr 16 '16 at 11:45
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I use NEEM for such problems = sucking insects, though whitefly is the only one with which I specifically have had trouble on my azaleas.

My understanding is that NEEM won't affect bees or other pollinating insects (unless sprayed directly on them). Not liking to get up early, I usually spray late in the day and I try to avoid spraying when the azalea is in bloom. For me that isn't a problem.

My recommendation is to spray the leaf undersides with NEEM as a dormant spray in fall/spring as a prophylactic to kill eggs if you've had a heavy infestation; otherwise only as needed and avoid spraying during flowering if at all possible.

The nuclear options are just a last resort, IMHO.

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