Are earthworms to blame for missing understory?

Hi everyone! I'm new here and am coming with lots of burning questions! We bought a 43 acre farm on a hilltop in KY. I've noticed in the forested part that there is very little understory. At first I thought the invasive bush honeysuckle was choking out the baby trees but then remembered the invasive earthworm problem - where they eat up all the leaf mold, completely changing the dynamics of the forest floor so most of our native species (that rely on leaf mold) cannot live or sprout, making barren understories.

Since I'm on a hillside, the runoff (we get a lot of rain here) is washing the topsoil from the forest down into a creek and then right out into the nearby river. In a recent rainstorm we got 4 inches in two days and lost an inch of soil from the path we had cleared as a hiking trail.

I'm wondering what to do about the missing understory and bare soil between trees. There are some small plants, just not enough to hold soil in place. The trees are mostly maples, hickories and other similar nut trees, and oaks. I was thinking of maybe trying some English understory plants like bluebells because they have adapted to living with earthworms, but hesitate to introduce another alien species.

Also, how are people finding the presence of earthworms affects permaculture mainstays like mulching under trees? When I lived near Philadelphia, our worms were so active there was nothing left on the soil surface after a few months except hardwood mulch, and even that would get digested after a few years. I'd rather not spend the money and fossil fuels to keep buying and spreading hardwood mulch, now that I have so much more land, and it doesn't seem sustainable to me to shred wood to use as mulch.

Best way to find out surely would be to dig a few test holes to see what's down there. When you say invasive earthworms you mean one of the species of earthworm that aren't indigenous to our country yes?

Can you coppice some of the trees for woody mulch? It doesn't need to be chipped, just cut in short sections. Maybe plant some trees or shrubs specifically for this purpose in the future.

Yes, earthworms aren't native to the forests of the Northeastern USA. Coppicing is a good idea. And right now there is a lot of dead wood we can cut.

We can't see what you are seeing, but do you think that the forest canopy is so dense that light can't filter in and nourish the understory in a satisfactory manner? Sounds like the forest has matured to a point, it's smothering itself. Could you open it up a bit more? Also, I could see some hedge laying (plashing) could be helpful to slow and hold back the water runoff and soil erosion, this by itself could let more sunlight in...

Maybe the forest floor needs more light. Maybe they are to blame. Have you tried transplanting some trees yourself. Maybe some critter is eating/moving all the seeds.

Is there something that you can spread around to take the place of the leaf mold etc that is still beneficial but that the worms won't eat? Don't have any answers just lots of questions

Earthworms are not indigenous to the North American continent at all. They are an invasive species introduced in the Colonial era via the ballast of docking ships from Europe.

Their presence in the soil dramatically altered the nutrient cycle in most forests, primarily by altering the quantity and nature of the composting biomass on the forest floor.

There's a very detailed and interconnected explanation of this in Charles C. Mann's most recent book, 1493 (which is an excellent read for general mind-blowing on a variety of topics regarding ecological and social evolution)

I'm pretty sure it's not too dense, since there are lots of patches of sunlight that get through to the floor in summer, and a lot of the trees are dying out (like 1/7). I saw this same thing in forests in PA, in the middle of summer the forest floor was bare dirt instead of leaf mould, and there weren't many plants between the trees. They blamed it on deer overgrazing, which was also a problem, but I think the problem wasn't as simple as just an overpopulation of deer. I've seen forests in Indiana where there was leaf mould, and you could see all kinds of wild ferns, columbine, etc. in the forest. They say worms only travel about 5 meters a year but if they get carried in water runoff then it's got to be a lot faster.

Half of our forest has the invasive bush honeysuckle as the only understory. I'm hoping I can just slash all of those out and lay them around to conserve moisture under the trees, but am a little fearful they can root and grow if I don't burn them.

Since you can't get rid of earthworms once they're here, it looks like we'll have to rethink what a "natural" forest is for Eastern North America.

I am very sorry to hear of such a problem and i wish i knew more to help. I agree with you on all you said, introducing outside species might help short term but turn into kudzu (an asian weed taking over georgia). I had hoped to find a link from the state of ky but all soil erosion links by the state are telling how to farm such slopes....surprise me for sure. I do suggest you call the state, I would start with the department of agriculture, to find local suggestions. Also the land universities generally have things to say on this subject.

For now, slowing down the water as it goes down the slope is all i can suggest, sounds like yu have logs around so position them cross slope. Make your path winding not straight up and down the slope. Yes mulch would help a ton too, I hope the state can tell you good plants for your area. Perhaps you can drop soome branches cross slope....not a great reason for trimming a tree but if the trees could speak i think they would sacrifice limbs to save their soil.

There is a bright spot i can see, sounds like your woods are perfect for ginseng growing. A profitable crop which would hold your soil in place....havested only after a long time so no need to think of it causing more erosion.

I went to lay down and I couldnt sleep until i said...if i recall those worms only live in the upper soil unless they are escaping cold. If I am correct in this you might gain much control by putting chickens there to eat them. Just a thought.

I found this site with a lot of good information about the bush honeysuckle, at least! They say if you cut the bush then immediately brush on Round-Up (I know, hate to support Monsanto!) it will prevent it from re-sprouting. They also offer understory plant choices that are native to the area. http://mdc.mo.gov/sites/default/files/resources/2011/08/cursebushhoneysuckle_2011.pdf

I brought up the erosion problem with the fellow I bought the house from. He used to work in Kansas in parks and said they put down dead branches horizontal to the flow of water to slow it and stop erosion. I've started doing that. I guess they can catch leaves and twigs to form small dams and slow the flow. Not unlike what some of you have said.

I'm wondering if running pigs through the woods in summer would help - they'd dig and eat the worms, apply fertilizer, and get fat on fallen nuts. Their ruts they dig would hold water so it could soak in. Biggest problem is fencing them in with so many roots and rocks in the ground. With over 20 acres of woods, tho, I don't know if my few pigs would make a dent in the problem. I guess I could try a test paddock. Biggest problem is the woods is very far from water sources, but at least it's downhill from the pond. Just really far to string hose.

http://threatsummary.forestthreats.org/browse.cfm?stateSearch=KY

http://www.invasivespeciesinfo.gov/unitedstates/ky.shtml#.UQAPU4aPtGO

There is some resources for you....for the honeysuckle that is. I woke up googling and I have gotten much information on invasive species and I think your problem is not worms, they are northern to you in areas scraped of dirt during the ice ages. This leaves that erosion is taking away your understory. The honeysuckle is likely your problem, the links above are government on this issue.

I think animals might easily cause erosion by digging. Others would be mre helpful when it comes to what will help, repost in animal forums imo. I think trees are simply living fence posts aren't they

i still hope yu will plant some ginseng ...it totally belongs on that hill some place.

I'll look into growing ginseng. What I've heard is it's really expensive to get the plants and they often just die because they need a healthy community of plants and fungi to thrive. That article on how to get rid of the bush honeysuckle listed other shrubs to grow in its place and several of them were things I've always admired but never grown (like witch hazel). I think that will be next year's project, but maybe over the summer I'll start transplanting seedlings and looking for seeds.

i imagine if yu spend money on seedlings you will be very much invested in them actually growing and on a hillside which presently seems to be slipping down hill. You may want to look into buying stratified seeds (apparantly the seeds like to hang out for 12 months before growing and the seed people do that for you) that isnt terribly expensive.

It does take forever before you can harvest it though...deep roots would hold that hillside in place. Hopefully if you plant some they will spread on their own, or you can harvest the seeds yourself which would keep more for you.

I am sure there is dozens of lovely things to grow on that hillside.

would try honey berries, and other fruiting berrys.

I would also plant some mints and a hardy thyme (fuzzy) up high, and see if they will take. They are very resistant to nibblers.

look at food forest mushroom cultivation on standing wood, some folks doing it commercially a little further south.

see if you can bring in quail or other ground birds, a lot of states are encouraging it now.

if you make slash piles for cover, you can usually keep ground birds around. will bring more foxes tho.


How many voles holes are there?
If you had that many worms, would expect a ton of moles and voles around too.

It is very odd to hear you describe a bare soil under a standing forest, even a fairly sparse one. Where is the leaf-mulch going? Some months and years of observation may solve this. Everywhere I've lived, I've used the forest as a source for mulch, not a sink for it!! Is the site sloping enough that heavy rains and wind are simply carrying the mulch away? Are there spots lower down where it is accumulating (perhaps for use?) The idea of laying logs and brush on contour to hinder this process is a good one. Until the erosion problem is resolved, I wouldn't get rid of any invasives....any plant is better than no plant. Coppice them and mulch the tops, and let the stumps sprout again for more coppice.
I wonder if it could be that the original understory plants and ephemerals were eradicated at some point, perhaps by an episode of logging, grazing, or farming, and simply haven't found their way back yet. You might try reintroducing some of these, preferably by scattering seed gathered for free somewhere, so that your investment and disappointment won't be so much if they fail. In particular, get things like bloodroot, trilliums, hepatica, trout lily, and such like thriving before you try ginseng!
If you are on site and game for some active management, you could try introducing some fairly aggressive groundcovers into the worst eroding sites. Periwinkle and English ivy come first to mind. But bear in mind that while these will trap soil and mulch and prevent erosion, they will be the only things growing there for the long term unless you come back and eradicate them later.

I think I'll pass on the ivy and vinca, they are invasive! The bush honeysuckle is allelopathic, so nothing can grow if it is there. I'll start looking for seeds for trout lily, blood root, etc. That sounds good. Maybe lots of seeds are there, waiting for the bush honeysuckle to go away so they can grow.

Deer eat leaves some, but in the forest in our yard in PA there were NO leaves left on the ground by mid-summer. Lots of those big fat worms that almost look like snakes, tho. We did have vole problems, but foxes eat voles, as do hawks and owls, which we had plenty of. Here there was a bad drought during the summer so maybe the leaves were gone just from deer and the understory is missing just because of the bush honeysuckle. I hope.

Another thing you might try is to lay out some contours and put in some narrow deep swales. You might have to leave gaps for the trees, and leave the larger roots crossing them, somehow. The goal is to trap runoff. Logs on contour with earth packed behind them might work almost as well, and be a lot easier. If you can improve moisture retention on site, you will improve drought resistance. The trees will grow more leaves which means more mulch, and the berms will catch the mulch. And because the whole system will be less moisture stressed, more plants can get a foothold, including the desired understory. Deer exclusion might be a tipping point too.....in many areas deer are overpopulated due to elimination of predators, proliferation of ideal thicket and regen habitat, and critical opinion of hunting. Baited electric fence is the easiest solution.
On the short term, try to be sure no organic matter and topsoil is leaving the site through erosion. Throw cut brush into any gullies or spots where water is flowing, or better yet make woven-brush and stake barriers.... The easy way to see this is to get out on the site in a hard rain and observe. (PDC students who think to do this during a course get brownie points!). Begin the work at the top of the slopes where water starts to run and gather and work your way downslope....

Thank you so much, very helpful!

I ran over to this forum and looked for this post when i heard about the free tickets to sepp. If you are on the mailing list you likely have heard about that already.

What I think is most interesting (for me anyways) is that he will be answering posts on another forum, under homesteading the earthworks forums. May I suggest you repost this problem on that forum and get expert opinion if possible. .

I would love to read his reply to this problem as well soy yu would be doing more than yourself a favor

I'd recommend terracing and building swales. The swales will keep the water and soil in place as will the terraces. If it's deer, I'd increase the edible bushes and if it's worms, where are all the birds? Maybe, you can improve the bird habitat by putting in more nesting areas and wildflowers - that will bring down the earthworm population.