Fungus, Pest, or ???

bluelytes · August 24, 2011

Any ideas what this could be and the cure, either natural or unnatural:

Its on my beet greens and swiss chards.

Best;
bluey

attml · August 27, 2011

I am not an expert by any stretch but that looks like a case of leaf miners to me?

http://www.tutaabsoluta.com/tuta-absoluta

RayR · August 27, 2011

That is leaf miner damage, I've had it before on chard. It's appearance on chard and beets could be misidentified as fungal since the affected areas are soft and look water soaked.
They usually only appeared for a short period of time here, so I just trimmed off and destroyed the infected leaves and that took care of it. If the problem is more persistent, check the bottom of the leaves for eggs. I would stay away from toxic insecticides, especially on leafy greens, a spray of a pyrethrin insecticide works good to kill any eggs.

bluelytes · August 27, 2011

RAY, (Or anyone else)
Pyrethrins dont seem to help. Any effective ideas on the toxic front?

Best;
bluey

RayR · August 28, 2011

The leaf miners tunnel inside the leaf, so they are fairly well protected from direct contact with pesticides, toxic or not. Also, by the time you see this kind of damage, the miners may have already left the leaf and dropped to the soil to go on to the next part of their life cycle.
I've never had a persistent problem with this, like I said before I just removed the infected leaves and sprayed the the plant with pyrethrin as a preventative if thought necessary.
Personally I don't use toxic insecticides in the garden and that goes double for leafy greens.
Other things non-toxic to people or beneficial insects could be used to discourage egg laying or to destroy any unhatched eggs, insecticidal soap, neem oil, hot pepper wax, etc.
This year I didn't spray anything on my chard except some neem oil that got on there when I sprayed my nearby summer squash for powdery mildew prevention. Last night I harvested a bunch of chard and found only one small leaf that had any leaf miner damage.

August 24, 2011	#1
bluelytes Tomatovillian™ Join Date: Oct 2006 Location: Pacific Northwest Posts: 250	Fungus, Pest, or ??? Any ideas what this could be and the cure, either natural or unnatural: Its on my beet greens and swiss chards. Best; bluey

August 27, 2011	#2
attml Tomatovillian™ Join Date: Jan 2011 Location: Annapolis, Maryland Posts: 222	I am not an expert by any stretch but that looks like a case of leaf miners to me? http://www.tutaabsoluta.com/tuta-absoluta

August 27, 2011	#3
RayR Tomatovillian™ Join Date: Jun 2010 Location: Cheektowaga, NY Posts: 2,466	That is leaf miner damage, I've had it before on chard. It's appearance on chard and beets could be misidentified as fungal since the affected areas are soft and look water soaked. They usually only appeared for a short period of time here, so I just trimmed off and destroyed the infected leaves and that took care of it. If the problem is more persistent, check the bottom of the leaves for eggs. I would stay away from toxic insecticides, especially on leafy greens, a spray of a pyrethrin insecticide works good to kill any eggs.

August 28, 2011	#5
RayR Tomatovillian™ Join Date: Jun 2010 Location: Cheektowaga, NY Posts: 2,466	The leaf miners tunnel inside the leaf, so they are fairly well protected from direct contact with pesticides, toxic or not. Also, by the time you see this kind of damage, the miners may have already left the leaf and dropped to the soil to go on to the next part of their life cycle. I've never had a persistent problem with this, like I said before I just removed the infected leaves and sprayed the the plant with pyrethrin as a preventative if thought necessary. Personally I don't use toxic insecticides in the garden and that goes double for leafy greens. Other things non-toxic to people or beneficial insects could be used to discourage egg laying or to destroy any unhatched eggs, insecticidal soap, neem oil, hot pepper wax, etc. This year I didn't spray anything on my chard except some neem oil that got on there when I sprayed my nearby summer squash for powdery mildew prevention. Last night I harvested a bunch of chard and found only one small leaf that had any leaf miner damage.