North American Fruit Explorers mailing list at ibiblio

[Michael Dossett <phainopepla@yahoo.com>]

Bill,

I thought I'd chime in even though I am by no means a sweet corn expert.  
Hopefully someone else will post their thoughts to the list as I am curious 
to hear as well.  I have no idea what the brown spots are that you are seeing 
after you cook.  I think if it was frass (the technical term for insect poop) 
 it would probably be very soft and water-soaked after cooking and probably 
wouldn't stick to the kernels.  I have had entirely dark kernels show up 
after cooking that looked normal before and I've always attributed that to an 
old ear that was past it's prime and/or a damaged kernel.

As for the kernels at the top being eaten that is interesting and without 
much more info it is hard to say.  It could be birds, they will certainly 
pick at the ears sometimes but they aren't usually a big problem, and 
generally aren't the same ones that go after fruit.  Are the ends of the ears 
open with the husks pulled away a little bit?  There is a caterpillar (Corn 
earworm) which will eat the kernels and sometimes silks.  Usually it starts 
at the tip of the ear (where the egg is laid) and works its way down the ear. 
 If it was this though, I would expect a significant amount of frass to be 
obvious when you first open and pull off the husks.  Sometimes European Corn 
Borer will eat the tips of the ear but they are more likely to just burrow 
into the stalk or the ear of the corn.  I think with you being in Nebraska, 
your county extension agent probably knows a fair bit about corn and it 
wouldn't be too hard to get an answer from them about it.  If you
 do, I'd be curious to hear.

Michael


Michael Dossett
Corvallis, Oregon
www.Mdossettphoto.com
phainopepla@yahoo.com


--- On Tue, 8/25/09, William C. Garthright <billg@inebraska.com> wrote:

> From: William C. Garthright <billg@inebraska.com>
> Subject: [NAFEX] OFF-TOPIC - Sweet corn
> To: "NAFEX List" <nafex@lists.ibiblio.org>
> Date: Tuesday, August 25, 2009, 8:10 AM
> I apologize for the off-topic post,
> but I couldn't find this online. 
> What are the brown spots that sometimes show up on my sweet
> corn AFTER 
> cooking?
> 
> They don't look too appetizing! Heh, heh. Is it, er,...
> insect debris 
> (the politest term I could think of) from inside the cob,
> forced out by 
> the steam? But I haven't seen any other sign of insect
> infestation. If 
> not, what is it? It didn't show up except on the very last
> ears I picked.
> 
> And as long as I'm on the (off-topic) subject, I had
> something eat the 
> kernels from the tops of almost all of my ears of corn. I
> assumed that 
> it was squirrels, but this is inside my electric fence, and
> I haven't 
> seen any sign of them elsewhere in the backyard (normally,
> they'd go for 
> the peaches first). I'm sure it wasn't opossums or
> raccoons. None of the 
> ears were torn from the stalk. (Squirrels will usually try
> to carry 
> stuff away.) The kernels were just eaten at the top, and
> for an 
> irregular length below that.
> 
> So I'm wondering if it might have been birds. I've had a
> LOT of birds 
> around, attacking all my fruit, even when it was netted. Do
> birds eat 
> your sweet corn? This is only my second year of growing it,
> and nothing 
> bothered it last year. (And no bugs or fungal problems,
> either. I'm 
> amazed to have so few problems growing corn in Nebraska!)
> 
> Thanks,
> 
> Bill
> Lincoln, NE (zone 5)