Friday, 11 December 2015

The Greasy Cut Worm Mystery

We're growing maize for the first time this season, and have stumbled across a wee puzzle.

You may recall that biologically active soil is critical to us, and that we're pretty skeptical about the profitable industry that sells stuff to farmers and directs agriculture. So in buying maize seed we declined to spend $2600 to kill everything that could possibly threaten the maize crop. Instead we spent $520 on clover seed and hoped that nature would help us out.

To understand the greasy cutworm mystery though, we need to start at the beginning, which is buying the maize seed. First off, you don't just buy seed: you buy a whole package of inputs from the seed company and your local contractor. They work seamlessly together and help you see all the inputs.

Our vendors were surprised we'd consider direct drilling maize rather than full scale cultivation. Aversion to slicing up your soil structure and critters wasn't something they'd come across before.

Then we got to the poisons. Apparently there are three ways nature can screw over your maize crop: weeds, insects and microbiology. Most farmers buy add-on products that attack all three of these forms of life because that's all part of the perpetual war on nature being pimped by arms traders in the war.

Glyphosate is first up, to kill all the plants. Yeeaah, no chance we'll be using that, thanks. We've been getting great results here for five years renewing pastures without using any glyphosate. Plus there's all of that research on its terrible effects.

Next came the seed coating options with Poncho being the main focus. Uuum, no thanks, in fact we don't want any treatment at all please: just bare seed, ok?

That was back in May when we placed our order for 8ha of seed. Later, we decided that direct drilling wasn't a goer. Some of the paddocks we were using had been badly pugged and our fences weren't good enough to graze the others low enough. So we did cultivate, but without the glyphosate of course.

Then, as soon as we had a seedbed, we hit the paddocks with a slurry of lime, fish, humates, 10kg urea and 5kg of persian clover seed (pic left). The idea was to stimulate the biology, feed the soil directly, and sow a companion crop. We hope that the clover will dominate between the maize rows, grow high with the maize (adding volume to the silage) and pump nitrogen to it.

Sadly though, planting day was the hangover from the buzz of the clover slurry operation. Due to delays, the whole schedule was 2 weeks later than hoped and we were desperate to get it planted before imminent rain. We'd confirmed with the contractor to travel here, collected the seed from the local story and laid in enough of the critical fungal innoculants (trichoderma and mycorrhizae). I'd only innoculated a few bags of seed before I started wondering why it was pink, read the label and found that we'd been sent seed with the "standard fungicide". Rather than delay another week I carried on rolling the seed in fungi and wondering whether the "standard fungicide" would be a match for it. Pretty pissed off.

We complained vigorously of course. Turns out it's a systemic problem at Pioneer: when we say "bare seed" they hear "oh, just the standard fungicide please". That's why 'standard fungicide' is the last and greyest item on their website menu.

Anyway, the maize duly popped up and last week the local store manager called to say that she'd been touring the maize crops of the region and ours was unusual in not having (greasy) cutworm. The contractor said the same thing on Wednesday. Oh, and he's now also backing the clover to beat the weeds :)

So that's the mystery: how come we haven't got it and most others have?  Here are a few possible explanations that we've come up with (please suggest more in the comments):

  • luck;
  • cutworm avoiding high brix (healthy) plants; and 
  • Poncho killing off all the insects that are eating our greasy cutworm

We may be able to empirically test the first hypothesis (see below)

For option 2, we will test the brix later on. At this point the plants are too small to go ripping bits off them for testing brix. We'll also need brix from other crops for this test.

Regarding hypothesis three, imagine you are the farmer who has bought the Poncho and successfully annihilated all of the predators to the greasy cutworm, which then feasts on your maize. Do you feel lucky that the vendors can sell you something extra special to kill those little bastards or cheated that the Poncho didn't work?

By the way, Poncho is the brand name of a neonicotinoid and is therefore implicated in decimating the bee population.

That's all we know so far. Things I want to find out include

  • how many other crops in this region didn't use Poncho?
  • detailed breakdown of cutworm by use of Poncho in this region.

Fortunately the Pioneer rep is visiting next week. I'm sure she'll share this information with me.

2 comments:

  1. Its almost impossible to find sweet corn for the urban garden that isn't from neonicotinoid treated seed. I can only find some small choice from King Seed. That means that if people are buying seedlings rather than seed, they probably are neonicinoid treated too.

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  2. Really? That's awful. What's worse is that most people won't even know they're using a neonic.

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