A word of warning

[Snowfella]

If you have a Lophocereus scottii montstrose whatever you do don't EVER use Yates Folimat on it as an insecticide. I did yesterday as I figured it to be to late in the season for a good soak using a systemic and this was what I came home to today.

You can tell where I managed to give it a good coating and where I only glanced it with the spray, coated areas have turned a sickly white/grey colour.

Just hit it with some water out of a spraycan to see if it washes off but my hopes ain't high at the moment.

[Chef's Foreskin]

Wholey shit ! Good to see you over here too mate

[Evil Genius]

Alright, here´s what i think that could have happened: You put the spraying bottle too close to the plant while you applied it. Some insecticides that are sprayed cause something thats called Ice-Damage on the plant if you put it too close. Its because the aerosol that comes out is extremely cold at the part where it comes out the bottle. Just lack the practical terms right now but its a known problem with some pesticides and you should always keep safety distance of like 15-25 centimeters. Could have been something else but thats my first impression.

Edited April 27, 2012 by Evil Genius

[GoOnThen]

I hope it sorts itself out and doesn't get any worse.

I am very careful with everything I spray around my cacti these days

I thought I would add this to your thread if that's ok as the title should get most people to read it.

These photos are of a shroomery members cacti after he sprayed them with Multicrop Pyrethrum Spray (ready to use spray)

This only some of the plants affected

Not a happy camper

Photo of the side not sprayed

Cheers

Got

[Snowfella]

Could be that I got alittle to close for comfort with the nozzle, although others I sprayed was even closer and suffered no damage. Guess it either could be that the Lopho is more sencitive to cold or that it's sensitive to this perticular spray. Shame I don't have a can of compressed air handy or I'd try it on a small section of the healthy skin. Not like I could do it much more harm as it is. lol

[Heretic]

some cacti [ esp trichs ] are very susceptible to " pyrethrin burn " .

[Snowfella]

One very knowledgible member of another forum suspects it was neither the active portion of the spray or a flash freezer burn but the drivegas used in the aerosol. According to him the light hydrocarbons (butane, propane or whatever is used) can be toxic to plants if they accumulate on the skin.

Some straight quotes from the thread in that forum.

It won't be any consolation but the skin damage was probably caused by the propellant rather than the pesticide itself. These are usually a type of light hydrocarbon like propane or butane. If you spray lightly from a distance then very little of the propellant reaches the plant and it rapidly disappears. If you spray heavily or from too close then this happens. Stop spraying immediately if you see any sort of liquid forming on the plant because that is dangerous. The instructions say to spray from at least a foot away but you can still overdo it even from that range

Hydrocarbon toxicity is not caused by chilling. Perhaps surprisingly there is no clearly understood answer to what exactly it is caused by.

Sun makes it worse but you can burn them in the shade. Dry soil makes it worse. It does seem that the oils somehow dessicate plant cells and the results are very similar to windburn or sun scorch.

.

[CβL]

It looks to me like the discoloration has a "trickle" pattern to it, which would be consistent with it being chemical damage. It looks much more white in the valleys. Either way; indeed a solid warning worth heeding. Sorry that it had to be your plant to be the martyr, :/

[Hedonix]

yo, chronic effect!!

i had some bad scale on a peruvian torch down the back.. got bad because i didnt check in awhile.. a light confidor/pest oil mix did well.

cheers.

[naja naja]

ummmm, go natural guy's, natrasoap for me all the way. And only as a treatment, not preventative. It's got zero withholding period and is simply fatty acids of potassium salts.

[2Deep2Handle]

Got thankyou so much man......Multicrop Pyrethrum Spray (ready to use spray)...have a bottle of this lying around, and was just about to go hit all my trichos in the next week for scale with it, but i think ill just let the scale be.....orr naja naja naturasoap!

[Heretic]

Hi 2Deep, I wanted to reply sooner , but was hesitant to do so until certain of my facts . It took me a while to recall where I had read a warning about using pyrethrin sprays on trichs , after burning my own using it . Derek Westlund , in Adam Gottlieb's book " Peyote and other psychoactive cacti , p 63 wrote : " Thrips can be eliminated by spraying with pyrethrenes , an organically derived pesticide . This is fairly safe for Lophophora , but will damage or destroy Trichocereus unless it is rinsed within one or two minutes . The treatment should be done in the morning or evening . After a minute or two , the cacti should be rinsed and the residue washed into the soil to try and disinfect that too . Only the skin of Trichocereus seems to be affected by pyrethrenes , they have not been shown to cause harm by being in the soil " . Hope this helps , Tom

[trucha]

Cacti protect themselves from sun with a layer or flakes of wax. Dormant oil sprays and solvents can harm it which removes their sun protection. Don't know if that played a role but anything capable of dissolving wax should not be used on a cactus. (I heard of this happening with someone using orange oil sprayed as an insecticide as well.)

If they do not die from it they will grow the wax back but any sun scarring will be permanent.

Many times the components of interest are not in the label due to being considered part of the inert ingredients. You might call the manufacturer and find out what is in it?

I have not used pyrethrin on cacti as I feel physically sick any time I am around it so started avoiding it over 30 years ago.