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Emersed plant dying back

Lgtuk

Member
Joined
12 Aug 2017
Messages
79
Location
Hampshire
Morning all over the past month a small patch of my emersed growth has died back an seems to be slowly getting bigger.

Does anyone recognise what this is? It starts off as small white spots then over about 1-2 weeks the leaf dies off.

Should I cut it out or treat it or just leave it alone?
1511085982341380815122.jpg
1511086022135298427723.jpg
 
Hi all,
Does anyone recognise what this is? It starts off as small white spots then over about 1-2 weeks the leaf dies off.
It looks like the effect you get when you have an infestation of two-spotted (red) spider mites.

You should be able to see them under the leaves with a magnifying glass, and you may find, really fine, silk webbing on the older leaves. You can't treat it with chemicals, but you can get <"a biological control">, or you can try spraying with water twice a day (they don't like high humidity).

cheers Darrel
 
I'd trim it back - those leaves aren't going to recover - and then feed it.
 
It looks like the effect you get when you have an infestation of two-spotted (red) spider mites.

That was my first thought as well.. :) Or Green fly, maybe both. I had H.Tripartita growing emersed in different occasions and every time it got green fly infested and this bugger also damages and kills this fragile obviously very tasty plant for them in weeks time. At first i thought i could control it with daily spraying with water, green flies in the water are fish food they love it. But once the population gets realy established there is no spraying water against it.

Never tried anything else than Garlic they seem to hate it but is rather mild and not realy very effective. searched for some more remidies in grandma's box.. Sting nettle tea seems to be effective but couldn't find any data what this netle extract does to the water column. Nicotine (Tabaco tea) is toxic and i know this shouldn't end up in the water column to much. Water deluted with vinigar also seems to work, but a tad to much vinager also can damage the plant. Flies are a bit more easy to distroy, mites are a different story, these buggers are rather resiliant. Farmers sprayed so much nasties around and it's only short term effective, there are mite populations about resistant to everything available on the market and propagate faster than the ycan be killed if teh population is to big.. Except the realy toxic stuff, banned in most countries. Mites have a waxy coat on their exoskeleton this repels a lot thats deluted in water, petrol and alcohol based solutions disolves this waxy coat and makes it vurnable. Petrol is no go, alcohol could be an option.

The problem with such small plants also is, the bug lives and nests generaly on the underside of the leaf. Spraying on top of the leaf only killes that living on top. What lives on top is over population, means you already have a problem about out of control.. And getting to the underside of such a small plant. ?? Give it a try than you know what i mean. :( Mites also hate it soaking wet, so spraying a lot several tmes a day from the start can prevent it from ever growing out of hand.. But this is the same story as spraying bellow the leaves.. You would be spending more time on your tripartita than your wife.
 
Thanks for your replies. I will try the water method as this is on the rim of my tank and don't want to risk poisoning my fish with chemicals.

If all else fails I could gently lift it and submerge it for a week or so that should drop any nasties :)
 
Thanks for your replies. I will try the water method as this is on the rim of my tank and don't want to risk poisoning my fish with chemicals.

If all else fails I could gently lift it and submerge it for a week or so that should drop any nasties :)
At least a week, but than once these bugs are in the invironment they hide in the nooks and crannies and come back as soon is they smell something delicious. And mite is a realy resiliant destroyer. They make webs to nest, (our common name for it Spinning Mite instead of spider mite) so keeping it wet enough prevents them from building this web, but forgetting this for a few days your busted again, then spraying can work counter productive and atract funges because these webs. It's a nast cycle.. I still want to build myself a paludarium and this what if issue is still spinning in my head to find a safe as possible remidy. In a closed invironment natural predators are best.. But costly..
https://www.buglogical.com/spider-mite-predator/spider-mite-predator-amblyseius-californicus/
 
Hi all,
I will try the water method
It should definitely improve things.

When I started looking after our glasshouse it had the most amazing infestation of White-fly, Scale Insect, Mealy Bug and Red Spider Mites, and after while I didn't have an in date spraying certificate and after about a year of not spraying I was forced to get some biological control organisms. I'd never improved things with the White-fly or Spider-mites while I was spraying, and in late summer the White-fly were an active hazard to breathing.

I'd worked in commercial horticulture, where the answer to all pest problems was a liberal dose of <"Temik">, and I was still in the "better/more toxic/more frequent application will make things better", so I didn't hold out much hope.

Pretty soon it became apparent that some biological control worked brilliantly (Encarsia for White-fly), some was OK and some instantly escaped through the ventilators (Cryptolaemus). Phytoseiulus, the predator of spider mites was OK, they cleaned the plant you put them on but they didn't really spread to new plants.

They would <"be good in this situation">.

cheers Darrel
 
Hi all,It should definitely improve things.

When I started looking after our glasshouse it had the most amazing infestation of White-fly, Scale Insect, Mealy Bug and Red Spider Mites, and after while I didn't have an in date spraying certificate and after about a year of not spraying I was forced to get some biological control organisms. I'd never improved things with the White-fly or Spider-mites while I was spraying, and in late summer the White-fly were an active hazard to breathing.

I'd worked in commercial horticulture, where the answer to all pest problems was a liberal dose of <"Temik">, and I was still in the "better/more toxic/more frequent application will make things better", so I didn't hold out much hope.

Pretty soon it became apparent that some biological control worked brilliantly (Encarsia for White-fly), some was OK and some instantly escaped through the ventilators (Cryptolaemus). Phytoseiulus, the predator of spider mites was OK, they cleaned the plant you put them on but they didn't really spread to new plants.

They would <"be good in this situation">.

cheers Darrel
This sounds impressive. I have no idea what I would be buying though.

I will look into this some more.
 
and you may find, really fine, silk webbing on the older leaves.

that is a pretty large pic i noticed look the red square erea.. :)
1511086022135298427723.jpg



Look close, you wont need any magnifying glasses, you will see them running around in the webs at this stage. And
these are all babies. :nailbiting:

Knipsel.JPG
 
Good spot zozo.

Where have they come from I don't get it. Will I have to remove it all? Will they start attacking my other plants?
 
They obviously come from outdoors, can come from your own or neighbours Garden and yes the can attack other plants. The 2 spoted mite is in our language called the Bean spinning mite, probably because they are very attracted to bean plantattions and distroyed their fair share to get that name. But can be found on lots of crops, fruiting shrubs and trees, roses etc. So pretty common and once they moved in they usualy stay. I once started a brandnew greenhous, the first summer is was free of mites, the second summer they came and never went away. Till i shut it down, empty it, clean it out, keep it empty for a season and start again. Same story first season mite frree, second season back at the front with the guns. The stuff from the garden centre doesn't realy work, i sometimes had the idea they loved it and showered in it while singing a song. Thta's why new products are searched an developed, this bug seems to build up a resistance rather quick. Like rats get resistant to rat poisson. The only stuff that realy works, is what Darrel linked to, but this is realy nasty stuff you can't apply without protection mask. I know this stuff is still around on the black market and highly toxic and criminal to use it. But some people obviously still do.

Anyway damaged leaves, the little necrotic dots, typical for mite damage doesn't recover. The mite punctures the leaf and this again is an entry point for other diseases to the plant. Once you are at a point where you see webs all over the plant from leaf to leaf, as in the picture above it actualy can be considered doomed beyond help, that's a very serious infestation.

Best is trim all that's damaged off, because it doesn't recover anyway, and submerse the rest.. And from there on, if it gets back out clean, if possible submerse it again once a week for a day or 2 to keep it clean. Tho i have no idea how effective this will be and how well bean mites survive submersed. We have water mites, so a non aqautic mite, mite :D survive very long submersed or swim out and wait.

As said i have a green fly problem in my emmersed tripartita, i started over 3 times now and it gets distroyed again everytime till now. :hungover: It's a very delicate little plant.. But i just go with the cycle of cleaning it out wait, replant and see again. Bugs are something you probably need to learn to live with if you are not a fan of spraying poisson. I'm not..
 
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Hi all,
But can be found on lots of crops, fruiting shrubs and trees, roses etc. So pretty common and once they moved in they usualy stay.......As said i have a green fly problem in my emmersed tripartita, i started over 3 times now and it gets distroyed again everytime till now. :hungover: It's a very delicate little plant.
Some plants always attract Red Spider Mites, it is quite amazing. I haven't apparently had any mites on the house plants for several years, but if I bring a New Guinea Impatiens (Impatiens hawkeri) into the house, and wait as soon as the weather warms up you get Red Spider Mite damage.
Look close, you wont need any magnifying glasses, you will see them running around in the webs at this stage. And these are all babies.
Perfect, that is definitively Red Spider Mite.
The stuff from the garden centre doesn't really work,
There aren't really any acaricides that work. Acetamiprid ("Bug Clear Ultra") is available to the home gardener in the UK, but I wouldn't use (or recommend using) it.
This sounds impressive. I have no idea what I would be buying though.
You get another mite (the red one below), the predatory Phytoseiulus persimilis, that only feeds on Red Spider Mites. You just open the packet and they come out.

About £11 from <"the link above">.


cheers Darrel
 
Hi Darrel, if I bought the red spider mites would I then be infested with them? This is in my house so a little worried I would then have to get something else to get them.

I have the nursery rhyme ring round my head of the old lady who swallowed a dog to catch the cat, to catch the bird, to catch the spider, to catch the fly oh why oh why did she swallow the fly....
 
You can use the Phytoseiulus without any worries - I use this for many years, every now and then, in my numerous house plants and especially in summer in my cucumber-plants in the green house ( cucumber ALWAYS get spidermite attacks ).
The Phytoseiulus will kill off the spidermites - and just die of starvation after. This ofcourse means you need to buy new portion next time the spidermites may appear.
 
You can use the Phytoseiulus without any worries - I use this for many years, every now and then, in my numerous house plants and especially in summer in my cucumber-plants in the green house ( cucumber ALWAYS get spidermite attacks ).
The Phytoseiulus will kill off the spidermites - and just die of starvation after. This ofcourse means you need to buy new portion next time the spidermites may appear.

Ok I will give it a try.
 
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