Sounds like you have done a good job so far. The alfalfa pellets will supply the nitrogen for composting so long as there is sufficient moisture to get the process started.

You mentioned incorporating these leaves into the soil, I don't think I would do that if you are trying to restore natural habitat. You mentioned lots of tree roots so that also sounds like a vote against tilling to me. I would probably leave it as a mulch on top of the soil since that is how nature does it.

Probably the most important thing in getting your new plantings to survive will be choosing plants that will like the conditions (your soil type, pH, Sun/shade, climate/microclimate, drainage, exposure, wind etc.) For the first season you will probably have to pamper the new plantings a bit with water, extra mulch, and keeping the weed competition away.

I am not sure of the exact speed of the decomp but I don't think that is the most important factor for your project.
Leaves and a little bit of alfalfa should be o.k. for a native woodland in general but it depends more on what type of plants and the characteristics of the woodland. Some natives do not want a nutrient-rich environment and some do not want the acidity of the leaves (but most woodland natives will not mind). A native plant well suited to the particular habitat should not need much soil amending but will benefit from mulch, some watering during the establishment period and some weeding since those invasives surely left behind some seeds and roots. I would not be inclined to turn the soil with all of those invasive seeds present. The other option would be to disturb the soil to germinate the invasive seeds and then kill them but I think that is not wise since the supply of invasive seeds is usually extremely large and will not be exhausted by this method. Your biggest challenge will be suppressing the invasives, make sure you kill them off as much as you can before planting. Newspaper or cardboard mulch might be in order to help suppress the invasives. You might also want to check the natives and woodlands forums. Another option is a cover crop that suppresses the weeds and is cut down prior to planting. Don't know if it is too late where you are for a winter cover crop or not.

Ok, I think I should not dig in (tilling is not an option anyway) the leaf compost, but let it stay on the surface as a mulch. I have cross-posted to other forums on this project but not about soils or mulch, I'm a bit confused as I have a couple of projects in the works and can't remember where I posted which. I didn't ask about soils in any of those posts though. I thought I'd best come here to find out about that.

I guess my primary question is how long it will take for those shredded leaves dressed with alfalfa pellets will take to become composted, in fall/winter, being shaded with no cardboard or newspaper below.

I did reply to one of your posts in another forum.

When I think of restoration I don't think of planned landscape beds... but when I think about mulching and compost I think about planned beds... but anyway terminology aside...

If you are preparing an area to plant woodland plugs, I think your plan to cover the area with leaves is good. I have such an area in my woodland yard. I cover it with leaves every year. Woodland plants like leaf mulch. I like to shred my leaves with the lawn mower to keep them from blowing around. I wouldn't incorporate the material into the ground (you'll disturb tree roots). I would let nature do the incorporating.

If you've already been adding leaf mulch for three seasons, you should have a good start on woodland soil amendment.

The alfalfa pellets would help the leaf mulch decompose faster, but I don't think its really necessary. The leaves tend to decompose quickly on their own (typically within one season). Native plants don't really need it. Woodland natives like to buried in leaf duff, so if its not all decomposed by the time you want to plant, its not a problem... its just mulch.

If your trying to recreate a native habitat, I'd skip the alfalfa. It's not needed. In nature, nobody comes along and spreads any nitrogen to help it along. Continue to pile the leaves, and let nature do the rest.

- I strongly recommend that you NOT try to incorporate the material into the soil. You will destroy the natural soil horizons that are no doubt there, as long as you leave the soil undisturbed. Furthermore, research done by the Ag Dept folks here showed that any organic material more than 2 inches below the surface will do no good at all. It's completely wasted. UC California Master Gardener's research on planting trees came to the same conclusion. Adding organic material to your back fill (in other words, incorporating it) at best does no good at all and in some cases adds to rot and disease problems. If you have an established woods, the soil structure you want is already established. Do not disturb it.
- I'm not sure why you are in a hurry to speed up decomp in a natural woods. There is benefit to letting it happen slowly. The blanket of material will keep soil cool in summer, help control erosions, help water holding capacity, provide a good environment for a wealth of biological agents and more throughout the year. Let it go slow.
- Adding nitrogen will make your mature trees grow denser leaf canopies, making it harder for your understory plants to get enough light. Go easy on nitrogen. I would not add any at all if you want plants under the trees.
- Woods generate their own leaf mulch every year and usually self-perpetuate a fairly healthy soil. I would not keep adding to much material to the woods. If you have some from your property and want to amend a little, that is good but don't over do it, and you certainly don't need to spend money buying or even transporting material from elsewhere to a wood lot. Gas is to expensive and I don't think you need it. Great for garden beds though! I add mulch into my orchards, but remember I take fruit out every year, so I'm restoring the balance, give some take some.
- I think it's a wonderful project by the way. My native environment is desert, not woods so I have very diferent things that I work to preserve. But I keep a little area for natives to grow. I try to encourage them just a little. They include
Desert primrose - the most amazing flower you would not believe would grown in the DESERT and what a fragrance
Die weed that the Indians used to color clothing and pottery, also a lovely fragrance.
Verbena with it's beautiful lavender explosion of flowers.
several others that are rather nondescript but part of the native mix.
My Grandfather, back in KY, used to encourage things like gensing, blood root, sassafras (tree), and others. What kind of natives are you going to try?

Adding some source of Nitrogen to a woodland garden may change how that Soil Food Web functions enough that the wild flowers may not grow properly. In its natural setting the only N any woodland gets is from the birds and animals that pass through, not a lot, and native plants that wopuld be growing there have adapted over eons to function quite well in that environment. Adding anything other than the natural materials that would normally get there can change the whole environment.

Thank you all for your input. I will just add my own, and the neighbors, shredded leaves over the area. I will leave them to decompose on their own. As I add plants I'll just make a small hole in the mulch to plant them. I have a tentative list of plants I'd like to use, pending a soil test to check pH levels. There are moist areas that will hold rainwater for a few hours, and some very dry. Most of the area is filtered high canopy sunlight with some denser shade areas and brighter and some direct light for a few hours at the woodland edge. Pretty much a mixed bag.

Some of the plants I'm looking at are:

Mertensia virginiana
Arisaema triphyllum
Polygonatum biflorum
Aquilegia canadensis
Geranium maculatum
Asarum canadense
Penstemon digitalis
Tiarella corifolia
Phlox divaricata
Sanguinaria canadensis
Stylophorum diphyllum
Trillium sp.
Iris cristata

I guess my semantics are not correct. I'm not really restoring this area. But I am trying to create a replication of an undisturbed woodland that use to exist here. For that I am only looking at plants that are native to my county and are fairly common in the woodlands around here.

We've been working on this area for three years now, and I think we've won most of the battle against invasives. We are going to start small with the plantings to see if that is the case. I wondered about the alfalfa because we want to get some things planted as early as March and the leaf layer may not be sufficiently decomposed by then, there is probably a 12" layer of them on there now. The baby plants would disappear with all that around them!

You can just pull back the leaves where you plant. Most woodland plants won't mind that situation and the leaves should help suppress germination of the unwanted plants. "Restoration" is the term that many use for what you are trying to do so don't worry about the semantics.
I found the book "Planting Noah's Garden" by Sara Stein to be useful.

Here is a link that might be useful: Planting Noah's Garden

Linrose: EXCELLENT job!! Good going.

Like everyone says, if you're going to use alfalfa meal, just use very little to help with decomposition. Maybe sprinkle a little bit every other year?

one I don't see that is native is pawpaw. They would do wonderfully in one of those wetter spots. And don't forget dogwood and crepe myrtle :) Oh and do you have any hickory trees in the woods?

We have lots of dogwood. And our forests here are oak-hickory so yes, there are hickories too. I haven't seen any pawpaw on our property though it does grow in some parts of the county. It may be too dry for it here. Crape myrtle is beautiful, but not native. It is native to China and Japan.