Scale on cacti. What their growth circle?

[mutant]

I remember Torsten saying that anyone growing cacti in a greenhouse would have in a degree a problem with scales. It seems he is right.

While I try to prevent their numbers by washing away with high pressure water, when I find an occurence at its begining, and sometimes try to remove manually the fuckers, in other occasions where the infection has proceeded away and/or with very spiny/ areolly cacti, it is virtually impossible to do anything but spray.

So I am using a combo of chems I was given by a local nursery , but I would really like to learn about their circle. Do they leave eggs / whatever in the soil? Do they prefer moist /warm atmosphere, thus the liking for the gh?

Could the winter cold damage their numbers? {say, I sprayed the infected ones and brought them out, where , especially at night temps fall pretty much}

I am supposed to spray them twice. How many days should I leave in between them sprayings? Should I spray for a third time to be sure?

[C_T]

i get it every year as the weather changes as i grow in an enclosed verandah surrounded by windows.

every change of season tends to cause an outbreak. going from hot into the cooler month, then cooler going to hotter months.

i use a tooth brush to scrub the skin. full eradication seems like in my environment will never occur! there's just not enough fresh breeze to keep their numbers down.

so i'd say good airflow in the greenhouse would be no:1 first line of defense. people talk about the neem oil type things, i'm too scared to use those things...

[mutant]

that stuff I used it toxic as fuck so, I dont really like it.

I would love to make a bio-weapon for scales. would nicotine be any good?

[applesnail]

http://www.ehow.com/about_5421412_life-cycle-scale-insect.html

[Hellonasty]

I HATE scale and have problems with them on/off. Depending on what type of scale you have treatment is different, I don't know the correct names and I believe there are literally thousands of different species but where I live in Sydney we tend to get three types

1. White - Small (less than 1mm), spread like fire and can cause a bad 'clumps' of infestation in less thank a week. They tend to start in shady areas (where you can't see) and spread surprisingly fast. Are dislodged easily with a strong bristled brush. But will come back eventually. They cause minor damage when caught early.

2. Black - Small (1mm) move/grow slower and more spread out with greater gaps between them. More difficult to dislodge with a brush but can be done. Again minor damage but cause scarring.

3. Brown - Large (1-8mm) Very difficult to dislodge, cause more damage than the others and are difficult to control. Can be removed with a blade, fingernail or sharp plastic.

I treat then in a few ways;

Bush them when I see them.

Mix up white oil, water and detergent and spray the effected areas.

Strong blasts of water at effected areas.

Some systemic insecticides appear to kill them off.

Having said all of this I still struggle with them any more ideas ?

[C_T]

the white (less than 1mm) ones are the type ive battle with for a few years now.

[Mr. Bowser]

For my tiny insect problems, I use about 10ml of limonene (naturally distilled from orange rinds) mixed with 10ml of IPA (99%) then dilute to 1 liter with H2O and spray this on the cactus. Seems to kill all insects, even heartier ones like ants

[nitrogen]

I get the white ones that come off easily, but they don't seem to cause any real damage or slow down the growth of the cacti - I still try and scrape or wash them off though