Author Topic: Scale insects  (Read 734 times)

saddad

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Scale insects
« on: April 09, 2021, 08:57:28 »
Morning all, :wave:
I have a Kaffir Lime in the house, which is small enough to inspect and clean to remove the little blighters but noticed a build up of them on my Apricot in the greenhouse does anybody have a good method to remove them... do they have an in the soil stage in their lifecycle?
I will but pruning off some new growth this week, but as the fruit is swelling I don't want to "poison" them, currently I rub the scales off and wash the stems with a weak detergent solution.  :sunny:

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Scale insects
« on: April 09, 2021, 08:57:28 »

Obelixx

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Re: Scale insects
« Reply #1 on: April 09, 2021, 09:54:19 »
Fingers crossed and touch wood I have not yet had a problem with scale insects but I do know they proliferate more easily in sheltered, indoor conditions.

If you want to stay organic your method of cleaning them off is good or you could maybe try nematodes for a bigger infestation.   The RHS also recommends a winter wash to control nymphs but too late this year.  Have a read of this - https://www.rhs.org.uk/advice/profile?pid=224
Obxx - Vendée France

Tee Gee

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Re: Scale insects
« Reply #2 on: April 09, 2021, 10:00:48 »

Obelixx

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Re: Scale insects
« Reply #3 on: April 09, 2021, 10:13:43 »
Excellent info and advice as always Tee Gee.  You are a star.
Obxx - Vendée France

Vinlander

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Re: Scale insects
« Reply #4 on: April 09, 2021, 11:33:44 »
Scale insects are difficult to kill without systemic insecticides and I'd never use that on a fruit tree.

It's best to remove the scales before doing anything else, but they can keep eggs (and "crawlers") under the shell, so afterwards you need to spray or wipe all over with a safe insecticide - good luck with that since derris/rotenone has been banned (almost certainly for the wrong reasons) - the only thing left is proper pyrethrum (not the permethrin family which have been tweaked to make them much more persistent in your plant and subsequently in you - the clue is in the "perm").

I have tried swabbing the stems with 70% alcohol, being careful not to put it the leaves - if only 10% of the leaves have scales you can remove them without  ill effects - but the scales have always come back - I've never been able to do all my citrus at the same time, and depending on the season there can always be little "crawlers" wandering in the whole area.

Cheers.



« Last Edit: April 09, 2021, 11:35:19 by Vinlander »
With a microholding you always get too much or bugger-all. (I'm fed up calling it an allotment garden - it just encourages the tidy-police).

The simple/complex split is more & more important: Simple fertilisers Poor, complex ones Good. Simple (old) poisons predictable, others (new) the opposite.

BarriedaleNick

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Re: Scale insects
« Reply #5 on: April 09, 2021, 13:44:03 »
We have some huge orange trees here which have a scale issue - no idea how to cope with a 20+ foot tall tree with are covered in scale.  There is a spray here but you need a license for it..
Moved to Portugal - ain't going back!

Deb P

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Re: Scale insects
« Reply #6 on: April 09, 2021, 19:47:55 »
I remember reading somewhere that methylated spirits cut through the scales protected coat but I haven’t tried it myself....I get them on my indoor orchids and pick them off by hand and immerse the whole plant in mild washing up liquid every so often....bit difficult to do to a tree though!
If it's not pouring with rain, I'm either in the garden or at the lottie! Probably still there in the rain as well TBH....🥴

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saddad

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Re: Scale insects
« Reply #7 on: April 09, 2021, 20:59:48 »
A lot of excellent advice there, thank you all. I would never use a persistent insecticide on anything I want to eat... part of the reason for growing my own fruit and veg! I agree with Alice in Wonderland...." If you drink too much from a bottle marked poison, it's almost certain to disagree with you, sooner or later..."

Paulh

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Re: Scale insects
« Reply #8 on: April 09, 2021, 22:56:25 »
I remember reading somewhere that methylated spirits cut through the scales protected coat but I haven’t tried it myself....I get them on my indoor orchids and pick them off by hand and immerse the whole plant in mild washing up liquid every so often....bit difficult to do to a tree though!

You just need a large enough washing up bowl - it's a question of scale.

(I'll see myself out.)

gray1720

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Re: Scale insects
« Reply #9 on: April 10, 2021, 17:05:34 »
GROAN!
My garden is smaller than your Rome, but my pilum is harder than your sternum!