Best way to deal with Root Mealy Bug?

[Conv3rgence]

Bought a few succulents and cacti at the swap meet market for pretty cheap this morning. As a habit, I usually repot a all new plants immediately to inspect the roots for rot, pests, and their existing soil mix.

I got this nice variegated aloe for $5 but upon inspection, I see root mealy bug. I've never had to deal with this before and I have quarantined the plant and its awaiting treatment. One other purchase, another succulent from the same seller, has traces of root mealy bug. Also quarantined.

Now, how do I best tackle this problem, and do I need to treat all my other plants? They were sitting close to my other plants from 8:00am until about 2:00pm. Would this be enough time for the little bastards to infect my other plants?

Here's the pics.

[Psyentist]

Hah, you wouldn't believe it but I just logged on here to ask the exact same question.

Did a whole lot of repotting yesterday and noticed root mealies on a few of the plants.

The thing is I don't want to unpot every single one of my plants to check them, there's just too many.

I'm looking at doing some sort of soil soak thing on them all with an insecticide, and repeating yearly. I hate to use chemicals but if it means plants not dying then I don't really have a choice.

Anyone have any good methods for this?

From the little research I've done it seems Rogor or Confidor could be used. Some people even said to use a soil wettener or even a tobacco tea.

What do you's think?

[theuserformallyknownasd00d]

Confidor pot soak should do it. Won't need to be for long, it just needs to be saturated. I've also used pyrethrum on the roots successfully of trichs and lophs BUT i hear this can go extremely wrong and cause rot for some people.

[coolname]

I usually just scrub them off with an old toothbrush whenever i repot. They don't seem to cause much damage. I have also dipped the root system in metho for a few seconds then rinsed with water and that kills em good

[Conv3rgence]

I'm currently doing the hot water dip method that I read about, supported by some scientist guys so it's not just internet rumour. Apparently, 10 minute dip in 120F (49C) water will kill the bugs. Some minimal damage to roots maybe, but will recover easily. Not recommended for sensitive plants with limited root system though.

Heres the link for the hot water treatment, discussion in a gardening forum suggested 10 minutes.

http://www.extento.hawaii.edu/kbase/reports/hIlandsc_rootmealyb.htm

Will see how this goes. Do I need to use chemicals on the rest of my nearby plants though? They were next to the infected Aloe for maybe around 6 hours from morning to just after noon, in outdoor shade. Do mealies move around in daylight?

Edited September 27, 2015 by Conv3rgence

[Conv3rgence]

It seems like these bugs go for pot bound plants first, none of my stuff near the infected plant in that 6 hour period was anywhere close to pot bound, all smaller cacti/succulents/rooting plants. All the big trichs that wouldve been a prime target were in another area, thankfully.

The hot water treatment is done, 2 dips on the main infected plant and 1 on the one that was slightly infected, with a smaller root system. Hopefully it didnt hurt them. I think I will let them dry and heal for 3 days.

How can I tell if the dips were successful?

The white webs remain on the roots though, what do i do about those?

Edited September 27, 2015 by Conv3rgence

[Psyentist]

I thought the white webs were the eggs.

That would be my only hesitation with the hot water method, it might kill the bug but leave the eggs behind.

But then I read people saying they're not really a serious problem for trichos and not to worry about them.

I think I'd prefer not to have little bugs sucking on the roots of my plants though.

Think I might go with the confidor pot soak. Cheers dood.

[Conv3rgence]

The webs are what they hide under, not necessarily the eggs. Afaik

Would diatomaceous earth mixed into the soil have any effect?

Edited September 27, 2015 by Conv3rgence

[trucha]

One problem to be aware of is the eggs can stay dormant for two years or more. Which means vigilance against a return for as long.

When I was still willing to employ insecticides a repeated drench with malathion worked wonders so long as it was repeated every few months for a couple of years. Imidichloprid works great too but can kill honeybees if flowers are present.

The best approach for me for some years has been to aggressively get rid of both the pots and soil when these pests are noticed.

They can be addressed by washing the roots clean using a softtoothbrush. Repeat as often as it takes. That generaly requires unpotting the plant twice a year to check for sign of new root mealies.

Root mealies are usually a serious pain to get rid of when they occur. For a container collection it can be a horrible pain in the ass.

I don't have much trouble anymore as something on this property eats all types of mealy bugs so they go away spontaneously. I have not been able to identify it yet but am working on that.

Watering with some added detergent (like ivory liquid) will help suppress them but does not get rid of them.

There are biological controls that do work (such as the soil fungi Beauvaria and MET-52ec) but they prefer more moisture than most cactus species so tend to be transient in their effectiveness.

Hypoaspis miles (a predatory mite which now has a new name I am forgetting) is supposed to be specifically effective against root mealies and similar soil pests but I have not used them.

Edited September 27, 2015 by trucha

[Psyentist]

Yeah, I've heard about the bee issue with imidacloprid but as it seems my trichos won't flower during my lifetime I don't really see it as a problem.

If I didn't have so many pots, there'd be close to 200, I'd bare root and check them all but I just don't have the time. Some are pretty big and spiky too!

I found this thread where evilgenius was having root mealy issues...

http://www.shaman-australis.com/forum/index.php?showtopic=27625

... and m s smith says he has had root mealys rampant in his collection for years. That they weren't really that much of problem.

I'm not sure what to do. Just leave them and wait to see if any plants start looking unhealth, and hope for the best. Or try to wipe them out now before they do any damage. There is a lot of ants around my yard though so I feel it could be a losing battle.

[trucha]

I've sure lost a lot of Chihuahuan Desert miniatures to them over the years. They don't seem to bother many sorts of cacti so whether you should care depends on what you want to grow. If you can't control ants you won't be able to control a number of pests.

We've stopped using poisons for anything except rats. Biological controls make more sense as long as the release site is adequately prepared for ensuring their survival. If not a person is throwing their money away.

[Psyentist]

There's not a thing I can do about the ants. It's seems there's some sort of ant superhighway running along the fence line at my joint. All I can do is try to dissuade them from frequenting certain plants.

I have a strict no ant policy on my plants.

They used to wreak havoc on my psychotrias by farming the above ground mealies. They even started bring dirt up into the lower branches of one to build a nest or something. But I went around daily, sometimes more, to disrupt them and ruin all their hard work, or make moats around potted plants to prevent access, and they got the picture eventually, touch wood.

But if they're also in the soil where I can see them harvesting mealies this scares me. Especially, like you say, for my little Mexican amigos.

They're in their own seperate little place at the moment that is relatively ant free and as they were repotted recently I'm confident they're alright at the moment.

I'm reluctant myself to use any poisons, especially if it's only precautionary for most of the plants. I've also looked into biological controls for other pests like spidermite and above ground mealies and think they're a great idea. But my outbreaks aren't that serious and I'm afraid they'd just relocate to the neighbours yards as I'm pretty sure I take more care with my garden than they do. Might have to look into this hypoaspis miles though.

I think for now I'll just have to closely monitor my more sensitive plants and see how it goes.

Thanks for the advice.