Please HELP!

[kath]

Have been growing potatoes for decades and have seen this problem only in the past 2 years but only lost a couple branches at most- never found the culprit. This year we're losing 10-20/day! Happens at night and during the day- have been checking 2-3 times/day. Branches are never right at ground level or below, but have been up to 12" off the ground. Started just before the 2nd hilling. Have checked the soil for cutworms, gone out at night until midnight with flashlights, have seen no holes or footprints, and have set small and large traps just in case. Thought maybe birds sitting on them, lots of rain/wind we had, but over the past week the losses have been consistent regardless of weather. At first we saw a lot of ants where the stems are emerging from the soil but with bait & DE they aren't around anymore...haven't seen aphids. Got some Sluggo Plus and sprinkled it around yesterday.

The cuts are clean, stem is nearly always still attached on the bottom. Doesn't seem that anything is actually being eaten. Kennebec not touched. Seems that the losses are all concentrated in certain areas. Have four 25' long rows and the Adirondack Blue row is taking the heaviest hit- grew that only last year and this year. Two out of the 4 rows no losses at all. One All Red plant and a few in the section planted with seed marked "Blue".

Any ideas? Afraid there won't be any leaves left in another week.

Thanks for any suggestions,

kath

[Worth1]

I have a tiny grub like thing that eats the top of the stem next to my elephant ear leaves and it falls over and dies.
That is the only thing I have personally seen.

Looked on line a bit and cant find anything for your situation.

[kath]

Thanks very much for checking for me, Worth! Yeah, I've googled about everything I can think of and haven't found anything either. What comes up most is the aphid/ant connection.

A grub-like creature makes the most sense, given how the plants are being attacked- just wish I could catch one in the act! The branches are usually broken within a couple of inches of the main stem and never right at the top of the plant- at least yet. Haven't taken a specimen down to the PennState office in Doylestown yet, but the last couple times I went there, it wasn't helpful and it's a pretty big round trip in a direction we don't often travel.

kath

[ContainerTed]

Kath, I can't see whether or not there is evidence of some kind of "bite" to sever the stem. Beyond that, could it be something like a large dog or ???? moving thru and breaking the stems? The stems look very "tender" and "stiff" as though they could be broken easily.

I would put a trail camera in that takes pictures of movement and will identify the culprits. I don't put a lot of stake on critters like rabbits, opossums or such. I think you would recognize damage done by deer. But I would have to ask if you have feral hogs/pigs. Pigs might be "passing thru" and that could cause breakage. But, they would also dig up the roots and destroy the entire garden.

Just trying to think outside of the box.

[kath]

Hi, Ted! Thanks for your input- forgot to mention that we have a fence that keeps out the critters you mentioned with the exception of baby bunnies which fit through the 2" wire mesh at the bottom. We usually see traces of what they've nibbled and usually catch a glimpse of them. No rabbits, large or small sited near the property yet this season. They just appear to be snaps, not bites. Nearly every one is still hanging on at the lowest point when we find it, not completely severed. No footprints or soil disturbance anywhere in the garden and nothing being nibbled either.

Wonder if I'm overdoing the fertilizer and creating tender, stiff growth- and maybe some varieties are more susceptible than others.

Don't know what a trail camera is- will look it up. Neither DH nor myself very techie.

Thanks again- appreciate your help.

kath

[Worth1]

Too much nitrogen will come tell you when the potatoes are dug up.
Those tell tale hollow crack/spots in the middle of them.

[kath]

Originally Posted by Worth1

Too much nitrogen will come tell you when the potatoes are dug up.
Those tell tale hollow crack/spots in the middle of them.

Good to know- hopefully won't see them...

[Worth1]

Originally Posted by kath

Good to know- hopefully won't see them...

Okay I guess I have to correct myself.
I read too much nitrogen at some university site years ago and now they say something different.
So I will pass it on to you.
It is called Hollow Heart.
https://www.google.com/url?sa=t&rct=...eW-KrEff4zRQ3C

[kath]

Originally Posted by Worth1

Okay I guess I have to correct myself.
I read too much nitrogen at some university site years ago and now they say something different.
So I will pass it on to you.
It is called Hollow Heart.
https://www.google.com/url?sa=t&rct=...eW-KrEff4zRQ3C

Thanks for the article on hollow heart, Worth. I had read about it in passing a while back but never really had a problem with it except one year, with one variety (a type of russet, iirc).

Think the problem is just very elusive cutworm critters who, hopefully, are no longer inclined to climb up and nibble potato branches.

kath

[ContainerTed]

Trail cameras are used by hunters to get pictures of animals such as deer or a sasquatch by taking a picture when there is movement within a certain distance from the camera. I do see your frustration with this one. But, I've also seen a raccoon climb all kinds of fences and still do their damage to the guarded zones.

If the leaves that are having broken stems are large, then sometimes wind can oscillate them and cause breaks. BTW, a good trail camera only costs about $55 to $100 bucks and can give you much more in value with knowing what the prowler, or the perpetrator, really is.

I used one in my garden to determine that I have more raccoons than I can battle on who actually is the real owner of my corn crop (or at least my intended corn crop). One row of corn (~ 50 plants) against what I think was about 20 critters who didn't want me to have them. I gave up and bought corn at 4 ears for a dollar.

[kath]

Originally Posted by ContainerTed

Trail cameras are used by hunters to get pictures of animals such as deer or a sasquatch by taking a picture when there is movement within a certain distance from the camera. I do see your frustration with this one. But, I've also seen a raccoon climb all kinds of fences and still do their damage to the guarded zones.

If the leaves that are having broken stems are large, then sometimes wind can oscillate them and cause breaks. BTW, a good trail camera only costs about $55 to $100 bucks and can give you much more in value with knowing what the prowler, or the perpetrator, really is.

I used one in my garden to determine that I have more raccoons than I can battle on who actually is the real owner of my corn crop (or at least my intended corn crop). One row of corn (~ 50 plants) against what I think was about 20 critters who didn't want me to have them. I gave up and bought corn at 4 ears for a dollar.

Thanks for the clarification about the cameras, Ted. Raccoons climbed the fence last year the night before the corn was ready. Don't know what they'd be after by the potatoes, and I think the damage would be greater. Each affected plant is losing 1 or 2 branches/day, gradually going up the plant. Think I need a mini-motion camera focused on 1 potato plant!

We had a couple of days of wind/rain, but the breakage has been happening for about 2 weeks and most days/nights have been relatively calm...nothing out of the ordinary. The damage, on the contrary has been consistently increasing despite the weather.

Btw, corn here is $7/dozen!

[ContainerTed]

Originally Posted by kath

Btw, corn here is $7/dozen!

The wife and I were in the grocery store yesterday. Yellow Sweet or Silver Queen Corn was 3 ears for a dollar. However, some local folks who bring their corn to the roadside to sell have my favorite Sweet Yellow Corn for 4/$1.00. If you buy a dozen, they usually throw in an extra ear.

[bower]

The only thing pest-wise that looks possible is some kind of cutworm. Think big fat caterpillar, nocturnal, hiding in the soil by day. Cutworms are usually slaying precious little seedlings, but I read that some cutworms do feed and cut higher up when plants are more mature. You could try lightly cultivating the soil between rows, to see if you turn up any culprits. Or you might try dusting the stems with DE anyway and see if that helps.


If the cause is purely physiological - brittleness due to ?? some growth/environmental conditions - then you should be able to snap a stem with your fingers.

[kath]

Originally Posted by bower

The only thing pest-wise that looks possible is some kind of cutworm. Think big fat caterpillar, nocturnal, hiding in the soil by day. Cutworms are usually slaying precious little seedlings, but I read that some cutworms do feed and cut higher up when plants are more mature. You could try lightly cultivating the soil between rows, to see if you turn up any culprits. Or you might try dusting the stems with DE anyway and see if that helps.


If the cause is purely physiological - brittleness due to ?? some growth/environmental conditions - then you should be able to snap a stem with your fingers.

Well, bower, think you are right...several days have passed since I sprinkled the Sluggo and this morning there were only 2 broken branches, so it seems the tide has turned! One was in an area that hadn't been affected at the time so I didn't treat that section of the patch.

Without a doubt, we were losing some during the daytime, which is odd, but I remember seeing some sort of cutworm high up on a brassica plant during the day one time in the past, so maybe it's the same type. Cultivating is difficult now since the plants are hilled up so high and big leaves of the lower branches (none of which have been lost to them) are covering the soil, and there is also that depression and hole that tends to remain where the potato stems emerge from the top of the hill, so it's harder to know just where they're resting. It's just really hard to find the little devils! A whole different thing than when they attack a row of spinach or brassicas where it's easy to scrape off the surrounding soil around the stem and find them. Very frustrating for sure, and wish I'd thought of the Sluggo sooner, but another lesson learned and hopefully I'll remember when the next onslaught ensues!

Thanks for the help everyone! It's nice to be able to count on the experience of other gardeners in a time of need!

Wishing everyone a successful season!

kath

[mrdoitall]

I had this happen to my potatoes last year.It was caused by a neighbor’s cat. I put up Hunting Trail Cameras and got pictures of the cat jumping on top of my chain link fence. Then jumping down into my garden. Then walked over my potatoes and jumping back on top of my chain link fence on the other side of the potato patch to go into the woods... It did this every night... It didn't seem to hurt the potatoes that much I had a great crop of potatoes...