Ants on Radishes

I planned to make a spring salad tonight, and what could be better than adding a few crunchy, spicy radishes to top off some micro greens? Radishes, like many vegetables, are so much better fresh from the garden that they almost seem like a different vegetable from what you get in the grocery store. Plus, they grow from seed very fast and easy in early spring.. This year, I am growing Cherry Belles from Territorial Seed. 

Anyway, I've been checking on the radishes fairly frequently lately, since they grow so fast.  About a week ago, I didn't see any ants.  Today - a lot of ants.  They are small and black.  They seem to be tunneling, as well as crawling on top of the soil quite a bit.

The radishes actually seem fine so far.  I didn't see any damage on the leaves, and most of the mature radishes' red shoulders look unharmed.  But perhaps the ants only just arrived and their damage isn't yet apparent to me.

I will try to post some pictures of them later today.

***UPDATE***

Oh, how wrong I was.  This evening when I pulled some radishes, I discovered some serious ant damage.  They appear to have shaved chunks off of the radishes.

First, here is a "before" picture of radishes I picked a week ago, with no damage:

Now here are the "after" pictures of the radishes I picked today:

    

One of the radishes was even worse - a mere splinter of a radish.  When I pulled the radishes, there were so many ants, it looked like the soil was moving.  Ugh.  Here's a close-up of the ants on a rock, where you could see them:

What do I do?  Most of my radishes remain in the ground, and I don't want to lose them all. 

***UPDATE***

Tonight I found the same bug on two of my radish plants.  The ants are still all there.  This second bug was nestled in the very lowest part of the radish greens, just kind of hanging out, not moving or anything.  The ants were moving all around them.

I picked the bug off the radish and held it in my palm to take a picture.  At first I thought the bug was dead, because it didn't appear to have any legs, and it rolled around in my hand like a dead thing.  Then the weirdest thing happened.  All I had was my phone to take a picture, so I fumbled around a bit.  While I was fumbling with the camera, all of the sudden the bug came to live and started wriggling.  It was like the thing was asleep, and then it woke up. 

I took a couple of pictures as best I could and then snapped its head off.

Like I said, I found these suckers on two different radish plants.  Perhaps they are the real culprits.  Thoughts?

***UPDATE***

I talked to Amy on the phone about the problem, and she said that the ants probably aren't the ones doing the actual damage. But ants are often a sign that there's some other pests at work you just can't see. For example, ants like to "farm" aphids - but I know what aphids look like, and there are no aphids on my radishes.

Amy suggested I try diatomaceous earth as well as Bt, both natural pest deterrents. these would take care of a variety of potential pests.

I had some Bt on hand, so I sprayed that on the radishes about 3 days ago. I don't have any diatomaceous earth but plan to go pick some up soon.

Results so far: the Bt seems to have worked!! It took a few days to see a noticeable difference, but this morning when I checked the radishes, I saw that the ants are almost all gone and the damage to the radishes seems to have slowed and/or stopped.

Broccoli Leaves and Aphid Poop

Amy,

Creatures are feasting on the leaves of my romanesco broccoli. The good news is: they left the gorgeous purple broccoli head untouched, and I'm probably going to eat it soon anyway, so no worries. This is the last of my romanescoes this year. I started with six plants, and the other five all matured much earlier this spring. They are delicious - very delicate flavor when steamed and served with butter and salt and pepper. For some reason, this one lonely broccoli took much longer to mature than the other 5. None of my broccoli plants showed any pest damage until now.

I peeked under the leaves and found some aphids (see below). But the aphid population isn't all that large. The picture shows one of the largest clusters that I found. Are the aphids causing the main damage, or is it something else? I would like to know for future reference and also to assess whether the problem might spread to my other veggies nearby, which include swiss chard, leeks, carrots, tomatoes, green beens, and squashes.

Rachel,

So, the good news is that the aphids aren't really a problem. I mean, get them off of there before the population explodes. If you have a few warm days, that little colony could overtake the garden. Seriously. Females can reproduce asexually. Each adult female can produce up to 80 offspring in one week. Each of those 80 offspring then produce 80 of their own, who produce 80 more. That brings us from 1 female up to 512,000 aphids in less than three weeks. Anyway, wipe them off. I assume you already have, but it bears repeating. Do this even though you're about to harvest the broccoli, cause they'll just create some winged forms, pop out a few males, and fly over to your tomatoes to start all over again.

Aphids don't take bites. They have piercing sucking mouthparts. It's like a straw. They insert this straw into the leaf and look for a vein full of phloem. This is the sugar/sap and basic life-blood of the plant. They drink a lot of this. Actually, they drink enough to poop out some stuff that is basically sugar. We call this honeydew. There's a lot of evidence suggesting that the manna the Israelites ate was Honeydew from a particular kind of insect. It's pretty sweet, and not at all poopy tasting. (and I probably shouldn't admit that I know that, but, whatever). Ants will eat it. Ants will actually farm honeydew producing insects, protecting them from natural enemies. So, while ants are not pests, they're a pretty good indication of a problem if you find them all over a plant. Anyway, you can see how the leaf has turned yellowish underneath the aphids. That's typical aphid damage.

About the bites. Are you sure that's not slug damage? I'm less familiar with slug damage. I always look for slimy trails, because I can never remember the size of their bites. Those don't look like smooth margins. You have a lot more experience with slugs than me, so I'll defer. I'm curious about your slug program, though. Have you ever used beer traps? Copper barriers? I've heard inverted melons work really well too.

If it isn't a slug, then it's probably some type of caterpillar. These things are voracious. Since you'll be harvesting soon, let's focus on preventative measures. Look for caterpillars in the early evening or late morning. A little Bt wouldn't hurt, just as a preventative for your nearby plants. I'd suggest that you at least remove all of the leaves right after harvesting. It might be a good idea to remove the plant and turn the soil.