"Stalk borer", horror, or hornworm?

Shrinkrap · July 11, 2021

On my tomato plants. I took off a stem where the really big hole is. Minor wilting, and dying leaves above. Will BT or spinosad work?

Yak54 · July 12, 2021

In my years of tomato growing I have never seen this phenomenon

PaulF · July 12, 2021

A borer of some kind. Make sure to open the stem and kill the borer. I had on ten years ago and it was a solitary worm thank goodness. The plant it got into was dead in a day. I killed the bugger (the caterpillar) and nothing else was infected.

I have read that spraying BT is one way to keep the worms away. Also putting a collar around the stem will keep them from climbing up the stalk.

brownrexx · July 13, 2021

I would definitely cut that stem open and then identify the caterpillar for future reference.

Shrinkrap · July 14, 2021

Thanks everyone!!

Shrinkrap · July 14, 2021

I cut it open but found nothing but the Jack's Dead Bug dust and a few aphids.

brownrexx · July 14, 2021

That is so strange. Looks like it bored into the stem and then left. Maybe some bug made a mistake and bored into the wrong plant and it was not able to eat it for some reason.

Shrinkrap · July 15, 2021

Here's someone removing one! I found a similar looking cat in two tomatoes from that plant.I thought she was going to cut herself with that boxcutter.

https://www.youtube.com/watch?v=Z2CFLGY9fx8

brownrexx · July 15, 2021

Looks like the tomato fruitworm especially since you found them in the tomatoes which is where they are usually found.

Shrinkrap · July 22, 2021

I found one!

brownrexx · July 23, 2021

I think that you have a tomato fruitworm who made a mistake and went into the stalk instead of a tomato.

They can be green, brown or reddish in color. You can Google some photos.

Shrinkrap · July 23, 2021

Thank you, and yes; that's what it is!

July 12, 2021	#2
Yak54 Tomatovillian™ Join Date: May 2009 Location: Madison, OH, zone 6 Posts: 421	In my years of tomato growing I have never seen this phenomenon __________________ Dan

July 12, 2021	#3
PaulF Tomatovillian™ Join Date: Jan 2006 Location: Brownville, Ne Posts: 3,212	A borer of some kind. Make sure to open the stem and kill the borer. I had on ten years ago and it was a solitary worm thank goodness. The plant it got into was dead in a day. I killed the bugger (the caterpillar) and nothing else was infected. I have read that spraying BT is one way to keep the worms away. Also putting a collar around the stem will keep them from climbing up the stalk. __________________ there's two things money can't buy; true love and home grown tomatoes.

July 15, 2021	#8
Shrinkrap Tomatovillian™ Join Date: May 2006 Location: N. California Posts: 693	Here's someone removing one! I found a similar looking cat in two tomatoes from that plant.I thought she was going to cut herself with that boxcutter. https://www.youtube.com/watch?v=Z2CFLGY9fx8 Last edited by Shrinkrap; July 15, 2021 at 10:58 AM.

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July 13, 2021	#4
brownrexx Tomatovillian™ Join Date: Feb 2016 Location: Southeastern PA Posts: 1,420	I would definitely cut that stem open and then identify the caterpillar for future reference.

July 14, 2021	#5
Shrinkrap Tomatovillian™ Join Date: May 2006 Location: N. California Posts: 693	Thanks everyone!!

July 23, 2021	#11
brownrexx Tomatovillian™ Join Date: Feb 2016 Location: Southeastern PA Posts: 1,420	I think that you have a tomato fruitworm who made a mistake and went into the stalk instead of a tomato. They can be green, brown or reddish in color. You can Google some photos.