White Spots on Lophocereus Marginatus

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bigdaddyscondition
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White Spots on Lophocereus Marginatus

#1

Post by bigdaddyscondition »

This Lophocereus marginatus has a florid infestation of white spots. Some kind of scale? I would appreciate any identification and treatment recommendations from our experts on this forum.


Lophocereus marginatus 3-Mark Campbell.jpg
Lophocereus marginatus 3-Mark Campbell.jpg (271.96 KiB) Viewed 2084 times
Lophocereus marginatus 2-Mark Campbell.jpg
Lophocereus marginatus 2-Mark Campbell.jpg (253.52 KiB) Viewed 2084 times
plantguy
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Re: White Spots on Lophocereus Marginatus

#2

Post by plantguy »

I wouldn't call myself an expert on cacti by any means, but I'd say it's scale. As for treatment I have no clue... For an id I would recommend a closeup.
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mcvansoest
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Re: White Spots on Lophocereus Marginatus

#3

Post by mcvansoest »

Yeah looks like some kind of scale. I would see if you can hose it off with highish pressure water, then wipe down with alcohol and/or insecticidal soap and find a good systemic. Water in the systemic and monitor for any quick return - hose again if that worked before if scale returns. Once the systemic kicks in they will probably stop returning.

At least this cactus is not too spiny so wiping it down is doable. If the plant sees a lot of sun I would not apply any chemicals to its surface until the sun it mostly gone so towards the end of the day.
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bigdaddyscondition
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Re: White Spots on Lophocereus Marginatus

#4

Post by bigdaddyscondition »

mcvansoest wrote: Thu Nov 03, 2022 8:40 am Yeah looks like some kind of scale. I would see if you can hose it off with highish pressure water, then wipe down with alcohol and/or insecticidal soap and find a good systemic. Water in the systemic and monitor for any quick return - hose again if that worked before if scale returns. Once the systemic kicks in they will probably stop returning.

At least this cactus is not too spiny so wiping it down is doable. If the plant sees a lot of sun I would not apply any chemicals to its surface until the sun it mostly gone so towards the end of the day.

Just saw this, mc. Thanks!
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