gunsmokex
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What do I spray corn silks to prevent corn borer/worms?

Sorry I know I read it on here somewhere but I know there is something to spray on the corn silks to "suffocate" the corn borers or corn worms. I'm thinking it was just vegetable oil but after I read a little more about BT tonight it mentioned it as well. Any advice? I know my silks are due to be sprayed because they've turned that purple hue.

As far as pollination goes I can't possibly collect and pollinate each plant so I'm just going to have to hope that mother nature has done her job. I have about 8 '40 rows, I'm definitely expanding the garden next year or maybe I'll say screw it and plant less corn.

On that note will this treatment prevent the silks from getting pollinated?

I'll be spraying the silks at various times from here on out becasue my corn is all a different levels of maturity. Yes I messed up and planted my rows too close togehter in a rush to plant it all. I'm just hoping that I get ears at varying times as it matures, not sure if it will work that way but we'll see. Either that or I'll have a bunch of tall green plants to till into the ground and get some nitrogen back this fall. The outside rows are looking awesome and the interior rows look stunted of course.

Anyways I just need to know what to spray is all.

Thanks,
Justin

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rainbowgardener
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I don't grow corn, but here's what Mother Earth News says:

Many gardeners get good organic control of corn earworms by using eyedroppers or small squirt bottles to place a few drops of canola or olive oil in ear tips, as soon as the silks show signs of drying. You also can use a standard solution of Bt (Bacillus thuringiensis) or spinosad in the same way.

Read more: https://www.motherearthnews.com/organic- ... z2aWbH3zwv

Corn works better planted in blocks not stretched out rows, for better polllination. And usually people do succession planting of corn - plant a block and then two weeks later plant another one and so on, until you are within 3 mos of average last frost date. That keeps you from having a huge pile of corn mature all at once and then none the rest of the summer.

You may have created your own version of succession planting. As soon as the outside plants are done, take them down, to let more sun on the interior ones.

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TheWaterbug
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gunsmokex wrote:I'm thinking it was just vegetable oil but after I read a little more about BT tonight it mentioned it as well. Any advice? I know my silks are due to be sprayed because they've turned that purple hue.
Here's the guide that I read, which includes useful information like the ratio (3 teaspoons per quart of oil), the dosage [about 0.5 ml (1/10 teaspoon)] and the timing:
“It is very important that treatment is done two days after full silk, when the silks are beginning to brown. Too-early treatment causes non-pollination
at the tips of the ears. I treated Incredible (the variety) perhaps a couple of days too early and had a fair number of ears that were not filled out. They would still be clean ears but just not filled out. If you treat too late, you will get less effective control of the corn earworm.”
I bought the BtK (description says BT but the detail says "var. kurstaki " and the oilcan from amazon, and I used corn oil as my carrier.

I applied wayyyy too much, because I read this article after I'd applied :D and had some residual oil in my ears.

I'll have to see if I can adjust the oiler or put a stop or something on it to control the dosing.

But I had full fill and no earworms, so in that regard it was a success.

I had 4 rows of 25' each, at 1' spacings, so 100 plants, and it took me about 20 minutes to oil all the primary ears. I didn't do the secondary ears because I didn't think they were mature enough, and then I forgot to go back. But I didn't get any worms in my secondary ears either.

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TheWaterbug
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Also, I was concerned about leaving the BtK on my corn, but both Oregon and Canada report no toxicity whatsoever.

The Oregon study, in particular, has experimental results from human volunteers :eek:
  • Eighteen human volunteers suffered no illness from eating 1 gram of Btk each day for 5 days.
  • Five human volunteers suffered no illness from inhaling 100 milligram of Btk each day for 5 days.
  • Bt has been used for moth control since the 1950's. There is little evidence that a causal relationship exists between health effects and exposure to Bt among human populations within aerial spray areas.
  • Researchers injected Bt into the bloodstream of mice with compromised immune systems for 27 days and reported no deaths.
  • Laboratory animals exposed to Btk by feeding, breathing, injection through the skin, and application into skin abrasions were not seriously harmed by exposures.

imafan26
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It also help to grow a tight husk variety of corn.

bcallaha
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Jal-Ut in an earlier post says he uses one of those bug zappers. I'm going to try that next year. I didn't have so many corn ear worms this year, but I had small black bugs instead.

Brad

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TheWaterbug
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bcallaha wrote:Jal-Ut in an earlier post says he uses one of those bug zappers. I'm going to try that next year. I didn't have so many corn ear worms this year, but I had small black bugs instead.
Here's the thread with James's zappers, and mine as well.

gunsmokex
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Well after all of that I decided to just let mother nature take her course. I'm not noticing any corn borers or signs so hopefully I'll be ok.

I decided that individually applying drops of oil to 320' of corn plants most with double ears was just too much lol my plant population is pretty high so quite literally it could have taken an entire day. I'll see how it goes but I've check and so far nothing. 8 rows at 40' = 320' corn at about 6" spacing = approximately 640 corns plants, double ears on some soo guestimate around 1000' ears of corn or so). I went a tad over board for my first year lol.

As for the bug zappers, yes they are a great idea in concept however my biggest draw back to them is two things, one the cost of electrity. Two the fact that light just attracts more bugs. I have a yard light and there are thousands of bugs just hanging out by it all night long. Back when we used to have hogs we had the bug zappers the ones up here are called "flowtrons" yes they work great and its great to hear the bugs fry but I'm afraid they'd get my beneficial bugs as well.

Someone did mention planting corn in blocks. Well that may quite possibly be true for smaller gardens I don't doubt that one bit. All in all its pretty much a myth though as long as you have enough corn and don't plant one continuous single row of corn. I have a stand of corn that is 40' long by 12' wide the whole block concept doesn't really apply because it actually is a "block" of corn a 40' x 12' block of corn. I mean I have pollen falling everywhere out there I did a little more research and the amount of pollen available for one just one corn plant is astronomical. I can see where it might be a problem when a person only has a few corn plants plus mine pollenated all at different times since the plants grew up at different maturity.

Anyways we'll see how this all turns out. It'll warm up next week so that should finish off some of the more mature corn anyways.

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rainbowgardener
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As you said, you did plant a 40 x 12 block of corn.

What will you do with 1000 ears of corn?

gunsmokex
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rainbowgardener wrote:As you said, you did plant a 40 x 12 block of corn.

What will you do with 1000 ears of corn?
You'd be surprised what one can do with 1000 ears of corn lol. Where I'm from if you scratch my back I'll scratch yours.

Feed my friends, family and coworkers all the corn they want. Bag and freeze a recipe my mom has that was passed down from my grandma and have all the corn I'll need oh probably for the next year. Sell what's left at the local free farmers market. I have lots of things I can do with my 1000 ears of corn, if you want some rainbow you can have some too. I could think of something else to do with it too after watching moonshiners haha!

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jal_ut
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Interesting that there are few bugs at all this year in my garden. No corn worms. I think it has something to do with the winter we had and the bugs didn't survive it well. I am not complaining.

I think 3 or 4 drops of oil on the silks as they start to turn brown will do the job. Here it seems the bug light is enough. For sure things vary from year to year.

What to do with all the corn? Eat some, freeze some, (We prefer to cut it off the cob for freezing.) Give some away, sell some, and still have a bit to go mature then dry for feeding the birds this winter.

Image

imafan26
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I didn't get any corn ear worm this year. I did plant a tight husk variety but some of the corn grew funny. One had the tassels coming out of the ear and one ear grew outside of the husk. I have had the tassel coming out of the ear before, but a first for husk-less corn.

gunsmokex
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jal_ut wrote:Interesting that there are few bugs at all this year in my garden. No corn worms. I think it has something to do with the winter we had and the bugs didn't survive it well. I am not complaining.

I think 3 or 4 drops of oil on the silks as they start to turn brown will do the job. Here it seems the bug light is enough. For sure things vary from year to year.

What to do with all the corn? Eat some, freeze some, (We prefer to cut it off the cob for freezing.) Give some away, sell some, and still have a bit to go mature then dry for feeding the birds this winter.

Image
I checked out a few ears today and no corn borers :-) Nice looking patch of corn you have there Jal. We cut ours off the cob as well, I forget what the exact recipe is but I'll definitely share it once I find out what it is again (the best recipes are stored in someones head and not written down). I just traded some of my corn for labor, all you can eat corn and in return I get my Polaris 250 Big Boss 4x6 tuned up and running properly.
imafan26 wrote:I didn't get any corn ear worm this year. I did plant a tight husk variety but some of the corn grew funny. One had the tassels coming out of the ear and one ear grew outside of the husk. I have had the tassel coming out of the ear before, but a first for husk-less corn.
Hmm wow that sounds interesting, the actual ear somehow escaped the husk silked and then started growing? Thats awesome! You should have photographed it as some kind of corn documentary, maybe timelapsed so one could see the kernels developing lol. Guess I never saw any tight husk varieties at the greenhouse though, next year I'll be going with true organic corn seed and not GMO corn.



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