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MockY
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Call Ghost Busters. Something is beheading my seedlings.

Ahh, fall is here and I could finally do a complete makeover of all my raised beds. I mentioned in earlier posts that the soil I initially had in them was subpar at best so I went ahead and removed half the soil and added bagged composted chicken manure, compost, peat moss, and a healthy dose of Azomite to each of them and mixed it up good. I will add home made compost and vermicompost once the new plants are established...if they ever will be that is.

I have an issue, especially in one bed, where the cotyledon leaves are removed just under where they attach to the stem, leaving a stump. I will attach pictures to further illustrate the issue.
In this particular bed all types of germinating plants are affected. Carrots, chard, radishes, and cauliflower.

I initially blamed slugs. I don't have a massive slug problem, but they do exists. So 3 times every night ever since things started germinated, I've gone out with a flashlight and thoroughly examined the beds. I've found no slugs in the beds, but a few every night could be found in various places around a yard, and sometimes a few at the base of one of the bed. I've eliminated every specimen I could find, and now 2 weeks later, I barely find a single slug, not even in the grass where they have always been located.

I did one night find 2 very small grey/black caterpillar look-alikes by 2 of the seedlings, but the tender plants were untouched. I have not found any of these before this night, nor after, and the destruction has slowly continued, even during the day.

Due to the high organic matter content in the soil, I can now find all kinds of critters but none have shown any interst in the seedlings. Just the soil. The most common one is a spider like creature no bigger than a fourth of a needle pin. There are thousands of them in every single bed, and they run around like they've been binge drinking energy drinks. I've eliminated them as a culprit.

I have in this bed only, found small droppings of birds. Only a couple, maybe 3, but it made me bit suspicious. Do birst do this...as in eating the tops of seedlings. But if so, I would think the other beds would have been effected.

How about the soil? Is the amount of composted manure to great for some plants, and soon after germination, they get burned and drop the cotyledon leaves? All beds have pretty much identical ratio, though it could obviously differs a hair, but not enough it would matter I would think.

The following oddety seems to only be applied to the radishes... I can find pieces of the leaves a few inches away from the plant. Just like something simply cut off a piece and left it.

Potential Culprits that I can come up with:
Slugs
Birds
The soil (too rich with manure and compost)
Extremely small caterpillars
Soil dwelling bugs extremely hard to see or not an obvious threat

I'll post pictures of some of the carnage, though it's pretty easy to picture what it looks like.
I'm very discouraged and out of ideas. Any help would be much appreciated.
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rainbowgardener
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cutworms.

Image

Little caterpillars - there are different colors of them. They come out at night and just cut little seedlings off like that. Very bad pest for totally destroying little seedlings.

This can be prevented by making a cutworm collar. Take an index card or something like that, glue it together into a cylinder. Plant your seedling, then put the collar around it, making sure it goes at least 2" down into the soil and at least 2" above the soil.

Small size dixie cups with the bottoms cut off work too:

Image

then the "worms" can't get to your seedlings.

Once the plants get bigger and sturdier, they are not so vulnerable to the cutworms any more.

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MockY
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Hmm, that is the look of the two worms I found one night.

There is a never ending stream of pests it seems. Been battling loopers, hornworms, random caterpillars, aphids, whiteflies all throughout summer. I have never had the chance to grow lettuce or kale yet due to this big pool of insects. On top of that, various diseases have plagued my garden (mainly multiple kinds of mildew), but I contribute most of that to stressed plants due to poor soil. Once I'm close to manage one thing, another threat emerges. I wonder how many seasons must past before I've experience them all and there are no more surprises.

I can't get a break it seems and at this point it's very easy to just go "to hell with this" and simply quit gardening. I'm however to invested in this so giving up is not an option....not yet anyways. What it does however is creating a very large dent in the enjoyment of gardening. I'm not really gardening...I'm just hunting for vegetable eating menaces. So infuriating.

Anywho, enough of my spewing anger at these pests, and I thank you for your answer. Now I know what to concentrate my hunt for. They are really hard to see unfortunately.

I'll put a collar around my most important seedlings, such as cabbage, and hope for the best with the rest. I can't really put a collar around a row of radishes...it's simply not feasible, nor fun.

At what point is it safe to remove the protection from these beasts?

EDIT: I found that live Beneficial Nematodes may be the only safe way of dealing with this fully. It's somewhat pricey, but thinking that this is one of few ways to save my seeds, it may be the way to go.

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rainbowgardener
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Bt (bacillus thuringiensis) is a bacteria that selectively attacks various caterpillars, including the loopers and hornworms (but is not effective against the cutworms). It is available commercially under a lot of different names like Dipel®, Thuricide® , Bug Time® and Caterpillar Control®.

Diatomaceous earth works against a lot of different garden pests, including the cutworms, slugs and snails, ants, aphids, and basically any crawlers. It is not a poison. It is the cast off silicate shells of tiny diatoms. On the microscopic level it has razor sharp edges (to our gross fingers it just feels like soft powder). It cuts open anything small that crawls across it, but is harmless to the rest of us. You don't know it, but you have eaten it. It is added to many stored grains to keep insects out.

Eventually what you need is to get your garden in better balance. If your soil is not good, your plants are weak and stressed and are more attractive to and vulnerable to any pests and diseases around. And you don't have the predators you need. For example, one of the predators of the cutworms is trichogramma wasps. They are teeny tiny stingless wasps (wingspan 1/50 th of an inch). The adults feed on nectar from flowers that have nectar in tiny florests, like buckwheat and sweet alyssum, all the carrot family plants if allowed to flower -- carrots, parsley, dill, fennel, etc.-- and others. The same flowers also attract other parasitic mini-wasps, including braconids that will parasitize your hornworms. Various birds will eat all the caterpillar pests, but you need to have bird feeders through the winter to keep them in your yard.

When you have a garden that functions more as an ecosystem, with a variety of birds, toads, macro and micro-predators , pollinators, flowers to feed these things, a wide variety of diverse plants, healthy soil and healthy life of the soil, then it will stay in balance and be a lot more self-maintaining. It takes a few years to get there, but that is what you aspire to! :)

Taiji
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I go through this every year at springtime for me. (April, May, early June.) I always thought that it must be cutworms, but in my case, I don't think it is. I may have a few, but I think it's something from without. I mean, the air, outside the fenced garden, wherever. Not something that comes from down in the soil. I now suspect grasshoppers. I'm not inundated with grasshoppers here, but at that time of year some always seem to fly away when I go into the garden.

So, I tried putting some old window screens over my seedling rows, and it has almost eliminated my seedling losses. Luckily, I have lots of old window screens around here for some reason?! You might try that. Loose screen material without frames work too. Don't know if it will solve your problem or not, but it did mine. Then, as rainbow said, when the plants get bigger, they're tougher. Hope it solves your problem. It's easy to put a screen down over a row of radishes or lettuce if the row is down a little bit below ground level. Then, if it doesn't work, you know something else is the culprit. Have you seen any grasshoppers around?

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rainbowgardener
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Grasshoppers and cutworms inflict very different kinds of damage. Cutworms literally cut the seedling in two, leaving just a stump. You can see in the picture I posted, how the stem is getting cut off, just a little above ground level.

Grasshoppers are leaf eaters, eating holes in leaves.

Image
https://www.ipm.iastate.edu/ipm/icm/file ... mage-y.jpg

If there's enough of them, or the problem goes unchecked, they will eat the leaves right down to the skeletons

Image
https://www.ipm.iastate.edu/ipm/icm/file ... damage.jpg

But coming out and finding your plant with a lot of holes in the leaves or even a lot of leaf skeletons, is a lot different than coming out and finding just a little stump. Cutworms are actually worse for seedlings, kill them overnight.

So you know which you have. Screens or row cover prevents things that come from above and land on the plant. Row cover would just seal the cutworms in with your plants and be worse than useless. That's a good example of why you need to identify what pest or problem you have, before you start trying to deal with it.

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rainbowgardener
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I do think it is interesting that you can often identify your pest without ever seeing it, by the kind of damage.

aphids and thrips and other leaf juice suckers leave scars where the leaf was pierced, but not holes. Aphids leave behind a clear sticky substance called honeydew. If there's a bad problem with aphids, leaves will begin to yellow as the life is being sucked out of them.

aphid damage:

Image
https://bloominthyme.com/wp-content/uplo ... aphids.jpg

The four lined plant bug is another leaf sucker, but it leaves behind a slightly different damage, lots of very small transparent/ discolored circles, pretty regular in size:

Image
https://gardeninacity.files.wordpress.c ... -32-31.jpg

Lots of caterpillars eat leaves from the edge in, leaving semi-circles chewed out of the leaf edges:

Image
https://pics.davesgarden.com/pics/2009/0 ... 604e1e.jpg

Whereas slugs and snails eat holes in the middle of leaves:

slug damage:

Image
https://www.em-sustainableliving.co.uk/b ... leaves.jpg

somewhat similar to the grasshopper damage, but more rounded, oval/elliptical and more regular.

and so on....

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rainbowgardener
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Sorry, it's late at night and my censors aren't working and mind is rambling....

Here's something I wrote here awhile back that illustrates more the garden philosophy I am talking about:
I think that we are really talking about three different models of gardening farming, not two (organic or not):

What we tend to call conventional/ traditional, but has only become "traditional" in my lifetime, since WWII. I call it chemical gardening: Gardening in monocultures ( a field that is all one crop, e.g. corn), plowing/tilling, synthetic fertilizers, chemical herbicides and pesticides.

Organic gardening (especially commercial organic farming)- Probably still monocultures, probably still plowed/ tilled, uses things like compost / manure/ compost tea instead of synthetic fertilizers, uses hand weeding or things like vinegar, citrus for herbicide, Bt and things like garlic-pepper spray for pesticides, no synthetic herbicides and pesticides.

What I call ecological/ natural gardening, related to things like permaculture and biodynamic gardening: No monocultures, very diverse plantings, no tilling, composting in the field, mainly using only what comes from the field and mulch and cover crops, companion planting, trap crops, interplanting, relying on beneficial insects, use of birds, toads, ducks etc to control pest populations, chicken tractors for fertilization...

So the chemical gardener sees the pest and reaches for some kind of poison spray. The organic gardener sees the pest and reaches for something like Bt spray. The ecological gardener sees the pest and tries to figure out how to adapt the garden ecology to keep everything in balance, and probably doesn't spray anything except water.

Of course most of us exist somewhere along this continuum and are not perfectly any one 100% of the time!

What I work towards being is the natural, sustainable gardener.

ButterflyLady29
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Another possible culprit is the pillbug or sowbug. I've accidentally brought them in in pots in the fall and they also cause very similar damage. I brought in one pot that had some little plants that I wanted to determine if they were a sedum or portulaca (the 2 looked very similar) and when I checked them closely a couple weeks later the little plants were just stem stubs. I found one pillbug in the pot and no cut worms. Many sites will state that pillbugs and sowbugs eat mainly decaying plant material but I have found that they will eat living plant material even when dead vegetation is right there. In my experience they are particularly fond of newly emerged seedlings.

https://www2.ca.uky.edu/entomology/entfacts/ef439.asp

Taiji
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I forgot about sowbugs and pillbugs. About 20 yrs. ago, when I had my biggest garden of my life, before our 20 yr. southwestern drought began, I kept losing all my corn seedlings as soon as they would peek through the soil. So, I have to admit it, being desperate, I bought a bran bait that had some chemical in it of course. I sprinkled it lightly as per the directions, so that you couldn't even see it in the rows. Next morning: hundreds of dead sowbugs or pillbugs, maybe both. No more corn seedlings loss. I think they took that insecticide off the market because I could not find it after that.
Even though my more recent damage resembled what cutworm damage would look like, I began to think it might be something else, so just did an experiment with a 2 foot row of beets or kale, which for me here are the most susceptible seedlings. So, I put a screen down over the row just to see what would happen. Presto, no more damage. I'm still not sure if what I have is grasshopper damage or something else, but at least I know it's something from not in the soil. I didn't mean to suggest that we all rush out and cover all seedlings with screen, but just test it out to see if it works. Now I do it for lots of seedlings since it seems to work here. I was mostly talking about plants still in the cotyledon stage or with teeny true leaves.

Just for fun, I googled the wacky term: "grasshoppers cotyledons" just to see what would come up. 3 or 4 sites did suggest that grasshopper damage on cotyledons or very young first true leaves resembled cutworm damage, just leaving a stump. One poor guy was even complaining that his marijuana plants never made it past the cotyledon stage because of grasshoppers!

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rainbowgardener
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One thing that helps against any of these is just not to plant such young seedlings. Baby seedlings with just a couple pair of true leaves are SO much more vulnerable to all of these pests and to drying out and dying if they don't get moisture every day (because their root systems are so under developed). Carrots and radishes have to be planted in the ground; root crops don't transplant well.

Your chard and cauliflower can easily be started in little pots in a more protected location and then transplanted when they get to be a sturdier size. I start most of my seeds indoors. I wouldn't put broccoli in the ground before it looked at least like this and usually bigger:
March broccoli seedling.jpg
March broccoli seedling.jpg (36.23 KiB) Viewed 3833 times
(cauliflower and broccoli look very similar at this stage)

As noted, even if you aren't starting indoors, you can still start in pots where you can baby them better.



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