European corn borer. http://entnemdept.ufl.edu/creatures/field/e_corn_borer.htm. They usally attack just as the tassels just begin to emerge. At that time contact insecticides are effective.

Problem: Corn borer starts in the whorl as tassels begin to emerge. ( Here in Georgia the old timers call them bud worms). I have no problem with them when I apply a contact insecticide to the whorl just as the tip of the tassel shows. One application is usually sufficient. Once they enter the stalk and lastly the ear, the plant is on its last legs. They are somewhat time dependent. Early plantings usally make it here with no intervention. later plantings May, June or later have to be treated. Bt works as does mineral oil for corn earworms, but there is no point in treating the ear for corn borers. Possibly Bt in liquid form would would work as a spray on the whorl, but I have not tried it. Contact insecticides kill the eggs, before the borers get started.

I sprayed them with Neem today. I have BT Thuricide on hand.

I'm a little confused though. I have some kind of small worm/catepillar right now eating on the foliage and down in the deep crevices of the stalk. We've killed every one we can find but we just keep finding more. From reading I thought this was a different worm than the one that gets in the ear and from what you are saying I can expect those also.

So if I am dealing with (or going to be) two different things please help me understand how to treat each one. I'm not clear.

What do I do for the ones eating the foliage right now?

I have 2 silk whorls and more coming soon. So you are saying to spray neem oil as soon as these begin to appear?

Also, I started this corn in July, my first attempt at gardening but next year I will do it in the spring/early summer. Are you saying I shouldn't have either of these if I plant it that early?

Thank you for your patience.

Yes two entirely different critters. Corn earworm is a fact of life for most of us. The moth lays its eggs on the silk and and the larva pretty much confine themselves to the ear. The traditional treatment is is to apply mineral oil to the silk after it emergesand before it strats to brown. Bt is not as effective because the larva have to eat the it ( stomach poison) Neem oil I have not used but you probably use it the same way. The corn borer attack the whorl where the tassel emerges. If it not stopped there, I don't have any effective treatment. Once it gets into stalk, it is hard to get to. Bt will kill any larva which eats it, but once they bore in they are not eating it. You may have something else (Army worms maybe). If so Bt works on them also.You rarely see a borer only the damage. The plants stunts, the tassel falls over and you will noticed tha stalk has been eaten from the inside.

Corn Earworms:
Is this sufficient mineral oil? https://www.amazon.com/Swan-Mineral-Oil-USP-oz/dp/B005BUNQSM/ref=sr_1_3_a_it?ie=UTF8&qid=1472855335&sr=8-3&keywords=mineral+oil

Do you spray the mineral oil? Do you mix it with something, water or soap or both?

So when people say they find a worm in their corn when they go to shuck it is that a corn earworm or a cornborer?

Next worm I see I will get a picture. From the looking at armyworms pics I *think* that is a possibility for what I have right now.

Agree with the above. But if you have a cat or worm actually eating the foliage, the leaves, then it is something else - a third potential. Corn borers bore holes into the stalk whorl but they don't eat leaves. Corn ear worms are ear pests and don't eat the foliage either.

Without photos of the pest we can only make guesses as to what it may be but photos of the common corn pests are readily available online. When one is new to gardening the easiest way to learn to ID pest is just to Google 'common ______ pests" (fill in the blank with the name of the crop).

Common corn pests photos and treatment info

Dave

Here are some pics of the worm/cats that we have on the corn. Apparently neem oil spray doesn't bother them. I've sprayed this one on my husbands hand and he curls up for a minute and then crawls some more. Some are darkish with thin white stripes and a yellowish/tanish head.

Others are darker almost black with a black head and yellowish stripes down the side only. This one looks like a fall armyworm from pics of those online.

If you'd compare him to the photos I linked above you'd see that it is an armyworm. See info about them in the link I posted above.

Dave

I did compare and read what you linked to. I stated I thought they were army worms (between the pics). I ordered some spinosad. I've sprayed them directly with neem oil (diluted) and it did nothing. I sprayed BT Thuricide on the plants today but I don't think that is the right BT. It's all I have on hand and it would be a few days before I can get some here. I read the spinosad would work on them (better than the BT) and I also ordered mineral oil for the corn earworms. I read all you guys linked (and more). I saw something about how to apply the mineral oil (5 drops to the silk whorl when it turns (or begins to turn brown). Hopefully my oil will be here (Tuesday) in time.

Thuricide is the correct Bt formulation for all foliage eating caterpillars but it doesn't kill on contact. You spray the leaves and then they have to eat it. Then they slowly die but it can take 48-72 hours. Same is true with Neem Oil and with Spinosad. They are not contact pesticides. They eat or absorb and kill caterpillars from the inside while repelling them too.

Dave

Oh! I understood that BT had to be ingested but I didn't know that about Neem or Spinosad....thought they were contact pesticides! Thanks for clearing that up! Well if BT and Neem will do it I should quit seeing these guys soon!

Hello! We transplanted corn into our garden and this morning the most mature one was broken off and appeared to

be eaten at. My husband found this little thing in the base. What the heck is it and how do I get rid of it? Thanks in advance!!!

Thanks again