Another "I Don't Know What I'm Doing" Thread

[ShadyStump]

So, apparently I take the same view of bonsai and gardening as the Soviets did with their early space program: Fail big sooner; learn more faster.

Inspired?
I am.

When we moved into our new home this past summer we immediately started planning our vegetable garden, including where we're planting LOTS of fruit trees.
There are also allot of ornamental trees planted all over by the previous owner, many of which are native to my state though not my neck of the woods. Identification is on going, but one way or another most will be removed eventually because their locations, while pretty, are problematic for our plans. Most of these are older, mature specimens that I would really like to take air layers of.
We're also on a budget, and trying make up for lost time. That means almost all our new trees will be taken from cuttings... ALLOT of cuttings.
So, the plan is to take as many cuttings and make as many air layers as we can this year, and many will end up staying in pots. If you do it enough times, you're bound to have some success on accident, and it's about that time of year here.

In preparation for this big push, a fistful of questions that I've been struggling to find acceptable answers to. Mostly, what problems can I expect to run into?
Air layers:
Some of the better looking branches I'd like to air layer are currently all but horizontal. How, and how well, can I make this work? I understand that when girdling at an angle, the roots will almost always come out at the lowest point, so I'm concerned about how this could affect the trees' growth after separation.
If I take an air layer from a mature fruit tree, is it still a mature tree that will bare fruit just as soon as the roots catch up? Or does it just look mature and we're waiting for it to grow up all over again?
What's your best cheap and dirty rooting medium for air layering with? We'll be spending our budget on building fences, planters, irrigation, etc. Not sphagnum moss by the pound. I've heard lots of things, but I'd like to hear what you lot have to say.

Cuttings:
Here there's mostly just a debate between my wife and I about how best to treat the rooting end: cut at a sharp angle to expose cambium while keeping everything intact, or scrape the bark just above the cut to expose even more cambium?
Which will be ready for planting in the ground sooner: hard wood cuttings over winter, or soft wood cuttings in spring, or about the same?

Thanks ahead of time!

 

[leatherback]

If I take an air layer from a mature fruit tree, is it still a mature tree that will bare fruit just as soon as the roots catch up? Or does it just look mature and we're waiting for it to grow up all over again?

this is one of the reasons for layering; once they know the flowering trick, they will keep knowing it.

Cuttings.. Normally a clean straight cut. But.. check the famous propagation of woody plants bible.

 

[luvinthemountains]

I took a layer off of a large, horizontal mulberry branch last year. It only threw roots in two places, but they were on opposite sides. While I still suspect that the effect of gravity on auxin flow probably plays a role in layering, and thus why vertical is best, this indicates to me that it is not necessarily universal - at least for trees that root readily like mulberry.

 

[ShadyStump]

this is one of the reasons for layering; once they know the flowering trick, they will keep knowing it.

Cuttings.. Normally a clean straight cut. But.. check the famous propagation of woody plants bible.

This is what I thought, on both counts, but I've come across enough contradictory claim (including my wife's) that I felt the need to get other opinions.

I took a layer off of a large, horizontal mulberry branch last year. It only threw roots in two places, but they were on opposite sides. While I still suspect that the effect of gravity on auxin flow probably plays a role in layering, and thus why vertical is best, this indicates to me that it is not necessarily universal - at least for trees that root readily like mulberry.

One I'm particularly excited about is a curl leaf mountain mahogany, one of those that's native to Colorado, but not around here. They are, according to my research, much more prevalent on your side of the continental divide. Don't suppose you could tell me anything about them?

 

[Shibui]

Fruiting trees are usually grafted onto a rootstock with known properties for disease resistance, size, cold hardiness, etc. Your layers will not have those advantages so the new trees may grow differently.
The layers will be more mature than seedlings but may still need a few years to grow to size. They often put on lots of vegetative growth and less fruiting wood for a couple of years. You don't really want a 2 foot tall tree loaded with fruit anyway because that fruit can come at the expense of growth. Some just stay small but fruitful for years until they manage to produce some vegetative shoots.

Most propagation notes advise a sloping cut below to expose more cambium. Some talk of a flatter cut but with a second acute slice to expose cambium. Either way will work as will a simple flat cut as we know from growing cuttings for bonsai where we want roots on one level. Exposing more cambium may give a few % increase in success but is not the only way. Some sources use a flat cut at the top and a sloping one at the base but that is usually so the grower can tell which way up to place the cuttings. Humidity, warmth and light are far more important factors than how the base is cut. Rooting compound definitely improves both speed and rate of rooting and is well worth the few $ for hundreds of cuttings.
Hardwood cuttings require less resources and equipment. Softwood cuttings root quicker but generally winter cuttings and spring cuttings will usually be ready to transplant around the same time. Hardwood cuttings can be larger so there is some advantage there. Some plants grow better from hardwood cuttings, others root better as soft or semi hard summer cuttings. I find it useful to try different methods to find what works with each different plant.

Horizontal branches will still layer. Even if roots only form on one side the new tree will live after separation. In my experience new roots will eventually grow all round when the new tree is planted upright and given the opportunity.

Best layering media is sphagnum for some reason I do not understand but any media that holds enough moisture and air will do. Perlite can work well but tends to dry out a bit quicker. Perlite/peat blend holds water well. Potting soil can work but may be a little slower to root than sphagnum. Peat or coir can be successful but has less air and can occasionally cause root problems as a result. Garden soil does not have enough air and is full of pathogens. Some plants will survive but others will succumb to disease before getting strong roots.

 

[ShadyStump]

Fruiting trees are usually grafted onto a rootstock with known properties for disease resistance, size, cold hardiness, etc. Your layers will not have those advantages so the new trees may grow differently.
The layers will be more mature than seedlings but may still need a few years to grow to size. They often put on lots of vegetative growth and less fruiting wood for a couple of years. You don't really want a 2 foot tall tree loaded with fruit anyway because that fruit can come at the expense of growth. Some just stay small but fruitful for years until they manage to produce some vegetative shoots.

Most propagation notes advise a sloping cut below to expose more cambium. Some talk of a flatter cut but with a second acute slice to expose cambium. Either way will work as will a simple flat cut as we know from growing cuttings for bonsai where we want roots on one level. Exposing more cambium may give a few % increase in success but is not the only way. Some sources use a flat cut at the top and a sloping one at the base but that is usually so the grower can tell which way up to place the cuttings. Humidity, warmth and light are far more important factors than how the base is cut. Rooting compound definitely improves both speed and rate of rooting and is well worth the few $ for hundreds of cuttings.
Hardwood cuttings require less resources and equipment. Softwood cuttings root quicker but generally winter cuttings and spring cuttings will usually be ready to transplant around the same time. Hardwood cuttings can be larger so there is some advantage there. Some plants grow better from hardwood cuttings, others root better as soft or semi hard summer cuttings. I find it useful to try different methods to find what works with each different plant.

Horizontal branches will still layer. Even if roots only form on one side the new tree will live after separation. In my experience new roots will eventually grow all round when the new tree is planted upright and given the opportunity.

Best layering media is sphagnum for some reason I do not understand but any media that holds enough moisture and air will do. Perlite can work well but tends to dry out a bit quicker. Perlite/peat blend holds water well. Potting soil can work but may be a little slower to root than sphagnum. Peat or coir can be successful but has less air and can occasionally cause root problems as a result. Garden soil does not have enough air and is full of pathogens. Some plants will survive but others will succumb to disease before getting strong roots.

Thanks for the detailed response! Much of this I already knew, but you have helped clarify some things.

I've worked fruit trees plenty, just not propagating them as more than an occasional experiment, so I understand the risks and potentialities concerning separating cuttings from root stock. That's part of why we're aiming at such a large scale. We'll know what's naturally disease resistant or hardy to our area after a couple years, and our losses there are mitigated by sheer numbers. Size is a matter of proper pruning, and I love smoking meat.

I had wondered about using straw as a rooting medium for layering. Chopped fine, and solarized to kill fungus, etc., it should retain water and stay fairly clean and intact for a year. Any thoughts?

 

[Shibui]

I have no first hand experience of using straw for layers but it should have reasonable air/water holding properties. I did see someone trying sawdust but don't think there was any follow up results of that trial.

 

[leatherback]

I had wondered about using straw as a rooting medium for layering. Chopped fine, and solarized to kill fungus, etc., it should retain water and stay fairly clean and intact for a year. Any thoughts?

interesting you suggest this..:
I have pulled a handfull of old grass-like leaves in the garden in fall and wrapped it around a juniper branch I intent to remove one day, and fixed in place with a few wires, in an attempt to see whether that will create roots. (In a batch of Juniper I worked on last year, some had a lot of muck stuck in the canopy and it had started to self-layer in there).

 

[ShadyStump]

Trees self-ground layering isn't uncommon, but self-air layering? That's something else all together.

Thanks, to both of you. I'll give it a try, and let folks know how works.

 

[leatherback]

Trees self-ground layering isn't uncommon, but self-air layering? That's something else all together.

tbh, I do not think it is
Fundamentally it is exactly the same

 

[Shibui]

Some species can and do self air layer.
Ficus are masters at it. New Zealand pohutakawa (Metrosideros excelsor) also produces abundant aerial roots.

I sometimes get roots growing from branches close to the ground on shimpaku in the grow beds. The foliage is so dense above that humidity is enough underneath for aerial roots to start to form but only really close to the ground.

 

[asdsuu]

Trees self-ground layering isn't uncommon, but self-air layering? That's something else all together.

Thanks, to both of you. I'll give it a try, and let folks know how works.

Would really like to hear how things are going with this, unless you were waiting for spring to try. A lot of great information from all of you, I'm very new to this so this has been really helpful and I have a million questions, but am holding them at bay as I continue to to research.