Integrated Pest Management, Golden Rule Style

Our Fava Beans aren't looking so hot right now. They are suffering, as they always do this time of year, from one of the biblical plagues so hideous it could only be referred to euphemistically as "locusts". Yes, I'm talking about Aphids.

Ours are black, and a little bit of research has me guessing that they are Aphis fabae, the Black Bean Aphid. They are the scourge of our Favas, and probably indicate something of which we should be aware (we are generally of the belief that most plants in any given crop will have pests or disease, but only the weaker specimens will succumb to the attack).

At any rate, we worry some about our beloved Fava Beans, high biomass producers that they are, and heralds of the coming of the Fava Bean Burger mentioned in an older post. Mostly, though, we worry about what other people will think when they visit the garden. So we kind of rush them past the Fava beds.
Until recently, of course, when we began to see the textbook example of what we preach in terms of pest management: Lay off the poisons, focus on a healthy system, then let natural predators step in. Most notably we have the Ladybug, which is our garden hero due to its status as a general predator. Once it has finished with the aphids, it will move on to other pests. Or, more likely, when it has eventually reproduced to levels too large to be sustained on the aphids the excess will migrate to the rest of the garden. So when the plants die (of natural deaths) in June or early July, we will have a ridiculous number of ladybugs spreading out for new grounds. A side-note here; Ladybug beetles and larvae both do plenty of eating, up to 50 aphids a day. And Recently a Dutch group called the Foundation Against Senseless Violence chose the Ladybug as its logo. Cute for us humans, ironic on an insect level...
Here we have an unidentified wasp species, which began arriving in droves a week or so ago. They hang out over the Fava Bean beds in the hundreds, maybe thousands, and create roving clouds in the rest of the garden. It isn't their eating habits that please us as much as their egg-laying habits. You can't say that for many things besides chickens, can you? These wasps, just a half-inch long or so, inject an egg into each aphid they encounter. The egg hatches, parasitizes the aphid, and then, when it has eaten all there is, leaves the aphid an empty shell (see left).
Here is another strange predator, which those more skilled or experienced might be able to identify. It is enough for me to know that, with a shape like that, it is not eating Fava Bean plants.
There we have it. If we had gotten wigged out by all those aphids and sprayed, dusted or otherwise applied poisons, the aphid population would surely have been affected. But so would the populations of all the predators attracted to the aphids. It is a basic law of predation that 1) there are fewer predators than prey and 2) the reproductive cycle takes longer for predators than prey. So when it comes to bouncing back from devastation, the prey will excel. Predator populations will come back much more slowly, leaving room for a great infestation before they catch up.
So here's to our ladybugs! May they always get their way in our garden.