CactiGuide.comcactus forum
cactus home cactus identification cactus tech care for your cactus learn more about cactus
cactus nomenclature where cactus grow cactus forum cacti pests and diseases why I grow cactus

Be careful what you spray

Trouble shoot problems you are having with your cactus.

Moderator: hob

Be careful what you spray

Postby SnowFella » Fri Apr 27, 2012 5:24 am

Not everything reacts in the same way it turns out. :?
Noticed some mealies in the back corner of the collection yesterday afternoon and desided to give them a spraying for good measure, to late in the season to go hitting them with a proper soak of systemic. So I hit everything in that corner with Yates Folimat, an aerosol insecticide that I've used in the past with no ill effect....just haven't used it on these plants before.
Got somewhat shocked when I came home this afternoon and found my Lophocereus scottii mostrose looking like this #-o
Image
You can tell where I managed to give it a good coat of spray and what bits I missed, all of the skin that I managed to cover has turned a sickly grey/white colour.
Going to try and hit it with water and see if it scrubs off but I doubt it's going to work, have a feeling it's the skin itself that have marked. ](*,)

Oh well, lessons learned I guess.
User avatar
SnowFella
 
Posts: 1685
Joined: Fri Jan 07, 2011 4:27 am
Location: Sydney, Australia

Re: Be careful what you spray

Postby tumamoc » Fri Apr 27, 2012 5:36 am

It could be worse. At least it will continue growing, and before you know it, that will be the botttom part of the plant. Better yet, one day it will just be one of many stems :dontknow:.
User avatar
tumamoc
 
Posts: 2024
Joined: Sat Sep 24, 2005 12:10 am
Location: Tucson, Arizona USA

Re: Be careful what you spray

Postby majcka » Fri Apr 27, 2012 8:04 am

Maybe it gets off with cotton stick and water???
Maja

Strange is fun, cacti are funnier!
My pics on Picasaweb
My pics on Flickr

Image
User avatar
majcka
 
Posts: 3857
Joined: Sun Oct 09, 2011 9:17 am
Location: Vace, Slovenia, EU

Re: Be careful what you spray

Postby SnowFella » Fri Apr 27, 2012 8:28 am

Tried that just minutes after taking the photo, looked promising when the skin got wet but the marking came back as soon as it dried. A member of another forum, I posted this in multiple forums for good measure, suspects that it wasn't the chemicals that did it but rather that I flash froze the skin by holding the can't nozzle to close as I sprayed. Guess that's just as plausible as the chemical beeing the culprit even though non of the others I sprayed from the same distance show any harm.
User avatar
SnowFella
 
Posts: 1685
Joined: Fri Jan 07, 2011 4:27 am
Location: Sydney, Australia

Re: Be careful what you spray

Postby hoteidoc » Fri Apr 27, 2012 11:06 am

SnowFella - Really hope it was the 1st theory rather than 2nd! I guess even if it's 2nd you still have a viable stem. Boy, I so glad we ALL don't have to make ALL the mistakes w/o sharing them. ](*,) So many things to continually be aware of! Please show a pic 2 - 3 wks down the road!
Peter
Once bitten by the cactus collecting/growing bug, there is no known cure!
There's no 12 step programme for Cactaholics...so I shall just have to get some more!!
User avatar
hoteidoc
 
Posts: 2131
Joined: Tue Jan 18, 2011 9:56 pm
Location: Finger Lakes region, NY Zone 6b

Re: Be careful what you spray

Postby iann » Fri Apr 27, 2012 11:34 am

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.

This stuff contains Omethoate! Oh to live in Oz, can't find good cacti but can get every insecticide under the sun :)
--ian
iann
 
Posts: 15556
Joined: Mon Jul 24, 2006 11:10 pm
Location: England

Re: Be careful what you spray

Postby SnowFella » Fri Apr 27, 2012 12:51 pm

So would that be a chemical reaction from the propellant or a physical reaction from the cold liquid propellant getting into contact with the skin?
Have to say I likely got to close as I remember seeing liquids forming on it as I sprayed, quickly evaporating and if I remember my school physics/chemistly that would draw even more heat away.
@Hoteidoc: don't mind if a screup of mine will keep someone else from making the same misstake. The more we know and share the better the chance no-one else will make the same misstake again!
User avatar
SnowFella
 
Posts: 1685
Joined: Fri Jan 07, 2011 4:27 am
Location: Sydney, Australia

Re: Be careful what you spray

Postby iann » Fri Apr 27, 2012 1:24 pm

Hydrocarbon toxicity is not caused by chilling. Perhaps surprisingly there is no clearly understood answer to what exactly it is caused by.
--ian
iann
 
Posts: 15556
Joined: Mon Jul 24, 2006 11:10 pm
Location: England

Re: Be careful what you spray

Postby daiv » Fri Apr 27, 2012 8:40 pm

Is this independent to being used in sunlight? In other words, does the same problem happen even if the plant is shaded? I had thought this was a result of sun acting on the oils. Is this yet another way for a plant to get damaged?
All Cacti are succulents, but not all succulents are Cacti
User avatar
daiv
Site Admin
 
Posts: 23597
Joined: Mon Aug 16, 2004 10:15 pm
Location: Long Prairie, MN

Re: Be careful what you spray

Postby iann » Fri Apr 27, 2012 9:24 pm

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.
--ian
iann
 
Posts: 15556
Joined: Mon Jul 24, 2006 11:10 pm
Location: England

Re: Be careful what you spray

Postby SnowFella » Fri Apr 27, 2012 11:44 pm

The sun had already set when i did the spraying and this plant is in a spot that only gets direct sun in the late afternoon so it cant of had anything to do with that. Noticed the damage before it had got any direct light.
User avatar
SnowFella
 
Posts: 1685
Joined: Fri Jan 07, 2011 4:27 am
Location: Sydney, Australia

Re: Be careful what you spray

Postby JeffWhiteDevil » Sat Apr 28, 2012 8:17 am

Sorry about the plant! and I thought it was bad when I washed the blue off a Browningia with Ortho 'Orthenex' spray. :(
User avatar
JeffWhiteDevil
 
Posts: 66
Joined: Wed Sep 16, 2009 8:37 am
Location: Northern Illinois

Re: Be careful what you spray

Postby Peterthecactusguy » Sun Apr 29, 2012 11:22 pm

at least yours is green. Mine have weird red growths on them. I do not know how that plant grows... I will post pictures. Maybe the red new growths will turn green or something..

And yes it is always a good idea when using chemicals to NOT spray them on plant tissues. Photo-toxicity seems to be a huge problem with the oils like mentioned above. It almost looks bleached.
Here's to you, all you insidious creatures of green..er I mean cacti.
User avatar
Peterthecactusguy
 
Posts: 8858
Joined: Fri Feb 19, 2010 7:49 am
Location: Black Canyon City, Arizona

Re: Be careful what you spray

Postby Steve Johnson » Mon Apr 30, 2012 1:44 am

Peterthecactusguy wrote:at least yours is green. Mine have weird red growths on them. I do not know how that plant grows... I will post pictures. Maybe the red new growths will turn green or something..

And yes it is always a good idea when using chemicals to NOT spray them on plant tissues. Photo-toxicity seems to be a huge problem with the oils like mentioned above. It almost looks bleached.

Yep, been there, done that. When I got my new collection going last June I did an Imidacloprid soil soak just as a preventative. Everything was fine, then 2 months later I thought I saw a few mealies on my Stenocactus multicostatus. I was using an insecticide-miticide-fungicide spray with Neem oil for my Habanero plants. Been working well for the Habs over 5 years, so I thought "well, that should be safe for the Steno". Wrong. The plant started showing orange spots in a few days, it was completely orange in a week, and after some more time went by the Steno was obviously dead -- phototoxicity. Learned my lesson there, and an Imidacloprid systemic is the only thing I'll use on mealies. As to spider mites, I've never had a problem with them, but if I do, I'll never use anything oil-based on cacti. Speaking of...

Ian has stated elsewhere that alcohol is effective. However, he was referring specifically to false spider mites at the time, although I believe it would apply to red spider mites as well. I also believe alcohol will not produce a phototoxic reaction, which would be a plus in spraying for mites. I'm not completey certain about that, though, so I've asked for confirmation about this several times. No response yet, but I'd sure appreciate getting an answer one way or 'tother. By the way, I'd be spraying cacti with alcohol out of direct sunlight. Since it evaporates quickly, I can see where it would have a definite advantage over oils and soaps given their residual effects.

@JeffWhiteDevil -- yes, I'm having fun with my cacti. Doesn't mean that I shouldn't worry a little bit and anticipate problems beforehand. Better that than let those problems get the drop on me as I go "what the f*** do I do now?" With that said, I confine myself to anticipating things that can be reasonably expected.
User avatar
Steve Johnson
 
Posts: 2138
Joined: Thu Nov 03, 2011 4:44 am
Location: Los Angeles, CA (Zone 10)

Re: Be careful what you spray

Postby JeffWhiteDevil » Mon Apr 30, 2012 2:52 am

I don't thnk you can go wrong using Imidacloprid. I have heard negative stuff on the use oils on cacti skin or on their roots but I have no experience with the stuff. The alcohol should be fine as long as you don't over-do-it, I use it myself upon occasion.
User avatar
JeffWhiteDevil
 
Posts: 66
Joined: Wed Sep 16, 2009 8:37 am
Location: Northern Illinois

Next

Return to Sick Cacti - Pests, Diseases, etc.

Who is online

Users browsing this forum: No registered users and 0 guests