Help. Is this spider mites? Solved

[Trevk81]

Looks like whatever it is has already damaged new growth

Any tips on removing them? I’ve been spraying them with SB plant invigorator in recent weeks but only just noticed this

[iann]

The damage doesn't look like classic spider mite damage, but I see a few specks in the photo that could well be mites.

[SimonT]

You could try using Bug Clear Ultra 2 concentrate- the active ingredients of this spray are pyrethrins and rapeseed oil.

[Davey246]

The giveaway with red spider is the webbing, although it is very often remarkably difficult to see (unless they have already run riot) as it is so fine.
Hold the plant up from underneath and tilt and orientate it in as many ways as possible against different angles of light. Sometimes the webbing is very close to the skin of the plant, but it will be there if you have RSM.
The other thing is that at any reasonable temperature, they are active, so if you stare CLOSELY at any plant with them, you SHOULD see them crawling around - they are very small, but still easily seen.

Still struggling? Buy a x10 or x20 loupe for peanuts from Amazon of EPay.

I doubt that there is RSM in your pic'.

[Trevk81]

Loupe and bug clear ultra added to the Amazon basket!

Can’t say I can see webbing, but I’ll try an have a closer look in the daylight tomorrow and angle them like you mentioned

I guess this is all part of collecting nature, bugs want to get involved!

I try quarantining new plants, any other tips for preventing pests?

[Pattock]

I see at least 15 mites in that photo (when opened in a new tab and embiggened). They are at the limit of visibility, but I would say two show the classic legs forward pose that indicates you have cactus mites. Not spider mites, which is why there is no webbing. The darkening may be a rot that got in through the mite damage. Or just rot that found its own way in, like rot does.

See this recent thread about cactus mites viewtopic.php?t=172814

I am not a cactus grower, so I would say nuke it from orbit. I am sure someone will give you better advice tomorrow.

And buy a cheap linen tester or loupe to check your other cacti. They shouldn't affect any other families of plants.

If you have a laptop and some money burning a hole in your pocket, a usb microscope can be helpful (or horrifying in this case). You can see them on screen and make videos of them or take still photos.

£104 is not bad for a specialist digital camera.
https://www.wexphotovideo.com/celestron ... o-1744900/

[Davey246]

The UK Biological Records Centre suggest that the mites (B. r.) are pests of not only Cactacaae, but also of Rhoeadales, which covers many common plant families/genera. That being so, it explains why it persists in the UK, as I find it difficult to believe that a pest totally specific to Cactacae would do so.

https://www.brc.ac.uk/dbif/invertebrate ... ectid=1452

https://www.merriam-webster.com/dictionary/Rhoeadales

[Herts Mike]

I had it right in the heart of Aloe haemanthifolia many years ago which did for it.

[Pattock]

Loupe and bug clear ultra added to the Amazon basket!

Can’t say I can see webbing, but I’ll try an have a closer look in the daylight tomorrow and angle them like you mentioned

I guess this is all part of collecting nature, bugs want to get involved!

I try quarantining new plants, any other tips for preventing pests?

Growing everything from seed is a bother but also a delight when they actually grow. I am surprised every time and I have been doing it for 45 years. I am definitely moving towards getting all my new plants as seed, where possible.

[Trevk81]

Yeah I’m starting to think that it’s cactus mites rather than red spider mites from what you’ve all described.

I’ve got a loupe on the way so I’ll try and visually identify them and then treat them accordingly. Hopefully I can at least control them and limit the damage.

Anxious the other cacti have them too now. Many nights ahead staring at them at x10 haha