caterpillar on brassica, possible ID

Let me preface this by saying that if there is a more appropriate "beginner's" forum somewhere where I ought to be posing these questions, please tell me. I almost feel like people in the permies forum have much more advanced things to discuss than my first, and failing, shot at planting kale... But there's so much knowledge here, I'm just going to stick my neck out anyway.

I found holes in my kale today, and this was the one leaf that had any evidence of the culprits. What are they and how do I get them to leave some kale for me?? I will also say that there is a lone white moth/butterfly (totally white, as far as I can tell, no spots) that has been looooving landing on my kale for weeks. I'm highly suspicious that it was laying eggs. Hmph.

Lots of "pests" on a plant may indicate less than ideal soil or weather conditions for the plant, so my personal recommendation is to remove by hand as many of the caterpillars and eggs as you can, and continue to improve your soil, rather than trying to kill the "pests" who may be indicating things are not yet just right (especially if this is the first time you've grown the plant). I will admit my "no kill" policy is not the usual one among gardeners.....

Thanks for your response. I'm thinking "out loud" here, tell me if I'm on the right track:

If there are pests, it means the plant is not producing any chemical defenses (secondary metabolites), right? And if it's only producing primary metabolites, that means the plant is focusing on basic survival?

And, if I leave the pests alone, make sure I water the kale sufficiently, and maybe do a soil test to see if the correct nutrients are there OR just go ahead and supplement with compost, I should know that the kale is healthy once the pests disappear because that would indicate the production of secondary metabolites, and therefore indicate a healthy plant?

...is that the basic idea behind your no kill method re: pests?

That's the idea!

Insects may not completely disappear, because they're part of the ecosystem, but they should decrease and their predators should appear if you provide habitat for them, which means providing a diverse garden of annuals, perennials,plenty of flowering plants, rockpiles and small bodies of water for lizards, frogs, toads, etc. You'll still need to share your food with some other critters, but you should be able to get a larger portion of it!

I agree with Tyler. I always overplant for my CSA. I know some crops with perform poorly and others will completely fail. This spring my chinese cabbage, tatsoi and pac choi were a complete loss to flea beetles. I looked up a natural remedy for flea beetles and it recommend planting a catch crop of pac choi or chinese cabbage! Who knows, that loss was probably protecting some of my other crops.

I do lots of companion planting which helps and I let lots of crops go to flower which provides pollen for your parasitic insects...esp. dill, cilantro, fennel.

I have sprayed organic pesticides in the past but I rarely use them now. Many are prohibitively expensive, mostly I use neem oil and Bt. I've used Bt twice in 3 years for hornworms and neem oil a handful of times. This spring I haven't had to spray a thing!

The soil is where you're work should be focuses. I highly recommend "Hands on Agronomy" by Neil Kinsey. It's much more in depth than an NPK and pH view of soil science. "Teaming with Microbes" is an easy ready for basic soil biology. Arden Anderson has interesting stuff on soil deficiencies and plant disease/insect pressure.

this may be the guy
http://en.wikipedia.org/wiki/Pieris_rapae

an alternative is using those spun row covers over your crops

http://gardening.about.com/od/toolschool/qt/Row-Covers.htm

duane hennon wrote:

this may be the guy
http://en.wikipedia.org/wiki/Pieris_rapae

I think you're right. I went back out to take a closer look and found the green caterpillars (their camouflage is good, I completely missed them the first time around) of a cabbage moth. I'm assuming the ones I took a picture of are just younger and not green yet. And, the moth itself made an appearance so I was able to see that it does have the gray markings. So, now at least I know what they are!

Ben Walter wrote: This spring my chinese cabbage, tatsoi and pac choi were a complete loss to flea beetles. I looked up a natural remedy for flea beetles and it recommend planting a catch crop of pac choi or chinese cabbage! Who knows, that loss was probably protecting some of my other crops.

Ooh this is interesting. So in some cases, the point of a companion plant is to defer the pests to that plant? I'd never realized that was a possibility. I hope your crop loss didn't hurt you too much, though. I'll check out the books you mentioned too, thanks for the tip!

Tyler Ludens wrote: Insects may not completely disappear, because they're part of the ecosystem, but they should decrease and their predators should appear if you provide habitat for them, which means providing a diverse garden of annuals, perennials,plenty of flowering plants, rockpiles and small bodies of water for lizards, frogs, toads, etc. You'll still need to share your food with some other critters, but you should be able to get a larger portion of it!

Makes sense! I do like biodiversity. I hope I can convince the toads, frogs, and lizards to cross the "great divide" that is the rest of my yard and enter the safe-from-dogs-zone of the garden.