Woolly aphids - how do you treat them?

[Wires_Guy_wires]

After using neem oil, pyrethrins, and two different types of systemics aimed at aphids, oil based insecticides, soapwater and ethanol.. They're still alive and thriving on my houseplants.

The bugs don't bother me much but the sticky honeydew they excrete is taking a toll on the floor and the windowsill. I mop up a sugary mixture twice a week and I'm getting tired of it.

I'm looking for alternatives to knock them out for good. Preferably something environmentally safe, but I'm prepared to pull out the big guns as well.

Have you ever gotten rid of them, and if yes, how?

 

[Forsoothe!]

Have you asked them nicely to leave? That would be both eco-friendly and polite. Bugs gotta live somewhere. Lots of insecticides will work, but you have to get it into every nook and cranny where they hide their eggs. Complete immersion in a bath (upside-down) followed by tenting in a big plastic bag for a few days will do it. Wear rubber gloves and don't breathe the fumes. Follow that with a systemic like Bayer 3-in-1 Rose twice a year.

 

[sorce]

I shear mine and knit little sweaters for mudmen in the Winter.

Sorce

 

[Mike Corazzi]

You're all being too kind. Coddle them and the next thing you know, you'll be facing legislation protecting them.

 

[Wires_Guy_wires]

Have you asked them nicely to leave? That would be both eco-friendly and polite. Bugs gotta live somewhere. Lots of insecticides will work, but you have to get it into every nook and cranny where they hide their eggs. Complete immersion in a bath (upside-down) followed by tenting in a big plastic bag for a few days will do it. Wear rubber gloves and don't breathe the fumes. Follow that with a systemic like Bayer 3-in-1 Rose twice a year.

Done that immersion stuff and it didn't work at all.
That's what's bothering me the most.

Terminator aphids.

 

[MrWunderful]

Nematoads?

 

[Leo in N E Illinois]

Integrated Pest Management - that is the topic to google, and the key take away is understand the lifecycle of your target pest. Then hit the pest with a management technique that targets its vulnerabilities.

For example, most "non-toxic" cures rely on mechanically washing away the juvenile phase and adult phases of the pest, where they are mobile, and easy to wash off with an insecticidal soap. Key is repeat applications at a rate short enough that the juveniles don't mature enough to begin another round of egg laying. The eggs are really hard to remove by "washing" with a soap. Similarly the alcohol based sprays dehydrate the unprotected juveniles and if you can penetrate the waxy coating of the adults. But there are always some eggs that don't get killed. So repeat applications at a short enough interval is key. In warm weather 6 or 7 days is all it takes for a mealy bug to go from egg to egg laying adult. So you have to repeat your applications at 5 days or less frequency. And you keep the reapplication up for at least 2 rounds after you see the last of the bugs. Because there is always the one you did not see.

I prefer the "toxic warfare". I usually use a spray mixture, that I mix myself. One ingredient will be a quick kill pesticide for knocking down the population, the second ingredient will be a long term pesticide. For example, if a pyrethrin group pesticide is appropriate, I will use a synthetic pyrethrin like Mavrik, by Sandoz, in a tank mix with a juvenile growth hormone disruptor like Enstar II. Two applications of this type of a mix, about 14 days apart will totally control your mealy bugs.

But these chemicals are not cheap. And they are not labelled for use in all states or all countries. You are in the EU, you need to read about IPM strategies utilizing chemicals approved in your own country.

 

[penumbra]

Are they woolly aphids or mealy bugs. I have never had woolly aphids on houseplants but I have have eradicated mealy bugs. I used weekly sprays of Safari plus Imidacloprid granules.

 

[Wires_Guy_wires]

Are they woolly aphids or mealy bugs. I have never had woolly aphids on houseplants but I have have eradicated mealy bugs. I used weekly sprays of Safari plus Imidacloprid granules.

You're right, they're mealybugs.
My bad, in Dutch they're called Wolluis (Wool louse/aphid). But in English they're mealybugs.
Pseudococcicae.

Is your imidacloprid acting as a systemic? I can make granules with that stuff.

 

[Shibui]

I found the reason for wooly aphid or mealy bugs returning is that some of them live on the roots below soil level so the normal pesticides never reach them. Those ones just keep on feeding and breeding to repopulate and move back above ground.
Systemic insecticides have been reliable because they translocate to all parts of the plants including roots. I understand systemics are not available in many places now. Imacloprid is an effective systemic in whatever form it is applied

If you have a product that treats the above ground ones you could try treating the soil as well to try to kill the underground bugs as well.
Bare rooting and washing the roots may work but also treat the pot and dispose of the soil so any left there can't get back on your plants. Obviously you will need to treat all host plants at the same time to be effective.

 

[Bnana]

Imidacloprid is not available for private use in the Netherlands as it has horrible environmental impacts.

 

[penumbra]

I found the reason for wooly aphid or mealy bugs returning is that some of them live on the roots below soil level so the normal pesticides never reach them. Those ones just keep on feeding and breeding to repopulate and move back above ground.

This is why I find the granules so effective as it prevents reinfection. It has also been very effective on scale outbreaks. The Safari spray gives me pretty quick knockdown and can also be used as a soil drench.

 

[penumbra]

Imidacloprid is not available for private use in the Netherlands as it has horrible environmental impacts.

I can appreciate that. I only use it on houseplants. If I have a real problem houseplant I get rid of it.
Safari too can be problematic for bees so I use this late in the day when bees are nesting.

 

[LanceMac10]

..collected American Elm showing some color...and no wooly crap!!

Agree w/ @Shibui that some aphids can reside at "ground level" or in little cracks in bark. It'll take multiple treatments along the entirety of the tree and even at soil level. Extremely persistent little rascals!! May even need some "digital manipulation"....good luck. Use whatever suffocates them.

 

[Forsoothe!]

What percentage of bonsai trees do you suppose flower? Seems to me damned few.

 

[hemmy]

Are they woolly aphids or mealy bugs. I have never had woolly aphids on houseplants but I have have eradicated mealy bugs. I used weekly sprays of Safari plus Imidacloprid granules.

Interesting, I’ve never seen root mealy bugs venture out of the soil and onto the plant when outside. But they can be darn hard to get rid of in soil. Safari is tradename Dinotefuran and is also available as granules in the US.

Here’s a paper listing some chemicals that worked in a research trial. Hot water soaks are also recommended and you can find the specs online. It may be feasible option for houseplants. I’ve used Dinotefuran and if I don’t see large amounts next spring, I will try switching to preventative beneficial nematode applications.

Efficacy of Insecticides Against Root Mealybugs in Pisonia brunoniana , 2012 *

This study was conducted at the University of Hawaii at Manoa, Waiakea Agricultural Research Center near Hilo, HI, under greenhouse conditions to determine

academic.oup.com

 

[penumbra]

What percentage of bonsai trees do you suppose flower? Seems to me damned few.

Not sure you posted this on the right thread, but it depends on what you mean by flower. All trees have a flowering response but most go unnoticed.

 

[Forsoothe!]

Not very many are allowed to flower in bonsai because of our trimming the tips keeping them compact are where most flowers present.

 

[penumbra]

Not very many are allowed to flower in bonsai because of our trimming the tips keeping them compact are where most flowers present.

This is true, but many more of my pre bonsai are allowed to bloom. I am speaking of hundreds of plants.
What is the relevance to this post? Is it in regard to the effect of insecticides on bees? If so, it is not clear.

 

[Forsoothe!]

Yes, bees, and not many of us have hundreds of flowering bonsai.