I've had a Chicago Hardy fig tree for two seasons now. I didn't overwinter it correctly in the first winter, so it started growing, grew lanky and I had to prune it hard it at the start of this (the second) season. It seemed to put out a reasonable amount of leaves, and looks healthy enough to me now near the end of the second season . However the bottom half of the trunk is leafless. I made cuts above three buds to "suppress the downward flow of a hormone, auxin," in an attempt to allow those buds to grow. None did.
From what I had read online, the topmost point of growth sends a hormone (auxin) down along the soft tissue of the plant to supress the growth of buds lower down on the stem/trunk than it. Making cuts into the plant above buds is supposed to stop this downward flow and allow buds to grow again. This was my first attempt at this process, so perhaps I didn't cut deep enough?

Is there anything I can (or should) do to promote the lateral growth of buds that will eventually turn into branches? I would like more lateral branches.

I only observed one main shoot of growth with single leaves growing off if it. How does a fig tree grow branches? The leaves drop as the plant goes into dormancy here, so do new branches grow out of buds?

I will include a picture of the whole tree, a close up of one of the cut buds, and a close up of a bud in the crotch of a leaf and the stem. What is that likely to become next year? Is there some way to tell fruit buds apart from branch buds?

Both of those buds are branch buds.
You will need to use a deep mulch for over wintering then remove that mulch once spring arrives so the tree will not be hindered.

I have one Brown Turkey tree that died back to the ground but came back this year with superior vigor (it is currently almost 5 feet tall and multi trunked).

If you treat this fig tree with loving care and mulch it deep the roots will be protected and it will come back next year with great vigor and you will end up with a very nice tree.
The biggest concern for northern grown figs is root freeze, hence the need for deep mulch over the winter months, after the leaves fall, lay on the mulch and do keep the tree watered, the roots will probably grow until the first deep snows arrive so water is important for those roots.

Bryant, I totally forgot to include my strategy for overwintering through into the third season!

I read that figs need to be kept in a temperature range from about 0C-4C , which is most easily obtained by keeping them in an unheated attached shed or garage. I have neither and I don't want to dig a hole to bury him, so I plan on laying the tree down sideways on the ground and covering it with leaves. Then I'll use two pieces of wood as long as he is, leaning edge-to-edge against each other to make a kind of elongated lean-to over the leaves, and lastly cover the whole thing with a tarp.

Would you recommend that I lay the tree down beside an outer Eastern facing wall of the house and then apply the leaves, wood piece, and tarp idea? Or would out away from the wall be better in terms of temperature regulation? (We got down to -25C the past two winters if I remember correctly so I'd like to be cautious.)

I hope that will be a kind of beefed up deep mulch approach. (I got this idea from the attached PDF).

I am actually glad those are branch buds, that means investment in energy gathering infrastructure, which means better returns in the long run.

I guess one way of approaching the situation may be to encourage winter die back up until a certain point on the trunk, and hoping that the root ball lives and throws up some vigorous trunks next season.

My goal is going to be to get the plant better established in a larger pot next season before I try anything like that though.

Thank you!

Think of the fig tree as if it were a rose bush that you are going to heel in for the winter.

Once the tree goes dormant, you are good to go, just make the trench and lay it down then cover.
Mine don't get that treatment since I live in the south but when I lived in Newburgh N.Y. I would heel them in, I used an old bed sheet then put on leaves and finally a layer of soil.
In spring (around the middle of March) I would take off the cover materials and stand the trees up, the cover materials became the mulch layer and that stayed around the pot and over the soil until the middle April when it was time to set up for spring and summer.
Same method should work for you.

Fig trees are pretty tough as long as they don't freeze completely.

Bryant,

It seems you have some experience with cold climate similar to mine so I want to ask you:

I planted some very young fruit trees (cherry, persimmon and peach), and over winter I would like to protect their roots with a thick layer of leaves, held in place with landscaping fabric (at least for the first few years).

When is it appropriate to lay down the leaves and cover them? If it is done too early, doesn't this leave open the possibility for rot or rodents? (- ie if its too warm out.)

Thank you,

Amjad

hau, Amjad, I would wait till the first frost is coming. At that time I would spread the mulch to the depth I wanted.
If you use landscape cloth you will create a micro climate perfect for rodents so I would not put that cover on until the first snow is on the way.
I have used strips of landscape fabric, put down in a weave type pattern (don't have to actually be woven over/under) and then landscape staples to hold the ends in place.
This way you are holding down the mulch but at the same time allowing air in, this will keep rot from advancing quicker than you want and it will help keep vermin from making homes in your mulch.

Thanks Bryant,

I am imagining the weave you are describing as something like a net. The point is to hold down the mulch, but not smother it with the fabric, correct?

I picture the tree's trunk being in the middle of this type of contraption (all made of individually laid strips) and instead of hooks, something to hold them in place in the soil..

I have said it before, and I will say it again. I am immeasurably thankful to everyone on Permies who has helped me out. It's actually kind of weird that most people won't ever meet, this is an artifact of the death of distance via technology.

At any rate, lets all keep the world, and each other.

Thank you,

Amjad

yes exactly like that, a net. You never know Amjad, there is a possibility that we might run into each other, my wife is from Canada and we are planning to visit the kids and grandkids once we have Asnikiye Hecka more in order.