Encouraging long roots

This is partly a question and partly a dump of info that I am picking up on gtd - want to be sure I am on the right path.  There are some plants that are considered to be marginally compatible with desert regions.  It seems that if they can be started - and nursed along for a couple of years - they will take care of themselves.  Can trees be started in a green house to encourage this process and then be transplanted into soil? I have seen root structures from green house grown plants that are longer than normal.  It is probably trees and plants with big tap roots that would benefit from this.

Long root systems can be encouraged by starting the plant (no matter which type) in tall containers. For trees that would be a container around 2 or 3 feet tall and at least 8 inches in diameter, PVC pipe is the easiest material to use for this.
The long pipe allows the tap root to grow down without curling at the bottom of the container.
If you use this method, your planting hole will, of course, need to be equally deep so the tap root remains going down once in the ground.

Redhawk

Trees with tap roots long enough for dessert climates are going to reach the bottom of a pot REAL fast.  Just consider that most desert trees, like mesquite, have a root three times the length of the sapling you see above ground.

But that's not really a problem. I have tried both starting in pots and direct seeding. I have not noticed a significant difference to survival between the two--except that it's really hard to keep up with watering direct seeded trees. I've even planted some potted trees that had well outgrown their container. I just cut off the wound up tap root so it puts out a new one. I transplanted a two-year-old African Mahogany (Khaya senegalensis) this year. Six feet tall. Judging by its green leaves in the middle of dry season its tap root must be three times that long at least.  I dug down four feet,  cut the tap root and moved it. With plenty of water it took just fine.

Mesquite, some acacias, and pithecelonium dulce are my hardiest ones (though I don't plant mesquite here because it's invasive in this climate.) Everything does better with loving care, but ideally just don't wait too long to plant them out.

This does not answer your question, I just thought it might be helpful:

Check into trees that have been started using the tall-pot method. It is used by the Arizona DOT for trees and shrubs planted along the highways especially in areas where irrigation is not possible. This potting method also works well with other rainwater management landscaping methods which direct water into areas where your trees and shrubs are planted.

The seedlings are started in sections of perforated 6' or larger PVC or ABS pipe about 3 feet long, filled with a suitable potting soil. The bottom of the pipe has a removable screen that keeps the growing media in the pipe during early growth.
Generally, a number of these pipes are arranged in a portable rack, so they can be drip irrigated while they grow to a size suitable for transplant.

A hole auger is used to prepare the planting site and a hydrophilic polymer is introduced at the bottom of the hole at planting. The tall pot is then placed into the hole and slid upwards around the seedling. The diameter size of the tall pot is determined by how wide it will need to be when the seedling is planted. The Water Management Group, headquartered in Tucson, AZ has pioneered these methods. The tall pots are reused to start a new round of seedlings.

Check out this site for photos and more information: https://watershedmg.org/project-site/flood-control-district-maricopa-county

What happens with this method is the seedling produces a longer taproot than that produced in the usual short, wide pot, and the side branch roots are "air trimmed" by the perforations in the pipe.
Also, the chance of producing side roots that can encircle a tree and cause root strangulation is reduced.

I hope this helps you with your project.

Anne Miller wrote:This does not answer your question, I just thought it might be helpful:

Can you please provide a link to your illustration? I would like to use it as a reference. It may be very useful as a resource for use in establishing drought tolerant forage for paddock-managed livestock.

Thank you all.  I am still considering buying some land in the desert...these posts will all add up to a more beautiful, green piece of the brown.

Mark Kissinger wrote:

Anne Miller wrote:This does not answer your question, I just thought it might be helpful:

Can you please provide a link to your illustration? I would like to use it as a reference. It may be very useful as a resource for use in establishing drought tolerant forage for paddock-managed livestock.

I have deciphered the printed names of these exceptional plants:

Drought tolerant, deep-rooted plants

Lead Plant (Amorpha canescerns)
Missouri Goldenrod (Solidago missouriensis)
Compass Plant (Silphlum laciniatum)
Heath Aster (Aster ericoides)
Big Blue Stem (Andropagon Gerardi)
Prairie Dropseed (Sparobolus heterolepis)
False Boneset (Kuhnia eupatorioides)
White Wild Indigo (Baptisia leucanthis)
Prairie Cord Grass (Spartina pectinata)
Pale Purple Coneflower (Echinacea pallida)
June Grass (Koeleria cristata)
Indian Grass (Sorgastrum nutans)
Porcupine Grass (Sripa tpartea)
Side Oats Grama (Bouteous curtipendula)
Switch Grass (Panicum vigantum)
Little Blue Stem (Andropogan scoparius)
Rosin Weed (Silphium integrifolium)
Cylindric Blazing Star (Liatris cylindracea)
Buffalo Grass (Bouteloua dactyloides)

I hope I have deciphered the tiny print correctly.

Would it be better to use a biodegradable material to make the long pots for the trees - at some point, just stick them in the ground and within a few months the pot has disintegraded?  It is not that difficult to make such things by hand.

"Would it be better to use a biodegradable material to make the long pots for the trees - at some point, just stick them in the ground and within a few months the pot has disintegraded?"

I think that might be a good idea if the tall pots could be made to last long enough to hold together before it was time to plant them.
Tree roots are pretty strong (the can shatter rock) so if they actually grow thru the pot material that would save a lot of trouble.
The only real advantage for using the PVC is that they can be used repeatedly. I suppose an experiment is in order.
You could have the basis for a business making biodegradable tall pots for nurseries if the experimental pots work out.

Thanks!  I will keep that in mind.  I was thinking that if a tree has an ideal environment to grow - especially for the root structure to easily grow downward - the side action would not be so prevalent and would help preserve the pots.   I am kind of excited about this topic. I love all biotopes and the idea of using native or native to desert climates to make the land more fruitful is very motivating for me.

If I may add one question to this...is there a certain tap root length that is going to make the tree "water sufficient"?

Mark Kissinger wrote:

Anne Miller wrote:This does not answer your question, I just thought it might be helpful:

Can you please provide a link to your illustration? I would like to use it as a reference. It may be very useful as a resource for use in establishing drought tolerant forage for paddock-managed livestock.

Sorry, Mark ...

It was from a previous permies thread; I don't remember which one; maybe something in "soil" or "greening the desert";  Dry land farming?

I saved it to my computer.  I refer to it quite often when choosing plants.

Tom Connolly wrote:
If I may add one question to this...is there a certain tap root length that is going to make the tree "water sufficient"?

Master your local fauna. Native trees, by definition, are adapted. Over time you can experiment with others.

Mark Kissinger wrote:
Can you please provide a link to your illustration? I would like to use it as a reference. It may be very useful as a resource for use in establishing drought tolerant forage for paddock-managed livestock.

It seems to be from the Conservation Research Institute (CRI) - Conservation Research Institute (CRI) - Educational Services and Products

The blurb says - "Root Systems of Prairie Plants Poster This much loved illustration by Heidi Natura displays the deep root systems of our natural grasslands and all that implies about the importance of rainwater infiltration and soil organic production. CRI owns the copyright for this image."

It seems to be available to buy as a poster, or here's a link to a smaller version as a pdf

Burra Maluca wrote:

Mark Kissinger wrote:
Can you please provide a link to your illustration? I would like to use it as a reference. It may be very useful as a resource for use in establishing drought tolerant forage for paddock-managed livestock.

It seems to be from the Conservation Research Institute (CRI) - Conservation Research Institute (CRI) - Educational Services and Products

The blurb says - "Root Systems of Prairie Plants Poster This much loved illustration by Heidi Natura displays the deep root systems of our natural grasslands and all that implies about the importance of rainwater infiltration and soil organic production. CRI owns the copyright for this image."

It seems to be available to buy as a poster, or here's a link to a smaller version as a pdf

Thanks. I have downloaded the PDF. I would consider buying the poster if I had a place to display it.
My situation now is pretty isolated, but I hope to become more involved in the local rangeland/gardening groups in the area around Kingman, AZ.
If you're in my area, let me know. I'd like to meet some permie people in my area!

Burra Maluca wrote:

It seems to be from the Conservation Research Institute (CRI) - Conservation Research Institute (CRI) - Educational Services and Products

The blurb says - "Root Systems of Prairie Plants Poster This much loved illustration by Heidi Natura displays the deep root systems of our natural grasslands and all that implies about the importance of rainwater infiltration and soil organic production. CRI owns the copyright for this image."

Some of these plants are available for purchase as seed or bare root plants at www.prairiemoon.com : a site for "natives for gardening and restoration." Some fun information there.

Tom Connolly wrote:Thanks!  I will keep that in mind.  I was thinking that if a tree has an ideal environment to grow - especially for the root structure to easily grow downward - the side action would not be so prevalent and would help preserve the pots.   I am kind of excited about this topic. I love all biotopes and the idea of using native or native to desert climates to make the land more fruitful is very motivating for me.

If I may add one question to this...is there a certain tap root length that is going to make the tree "water sufficient"?

Trees have three types of roots, each has particular jobs to do for the life and health of the tree.
Tap root; this is the anchor root, it prevents the tree from falling over in high winds, and other events that might make the tree fall (earthquakes, tsunami, etc.).
Bracing roots; These are the roots that spread out from the trunk, they also are for stabilization of the tree acting both as braces and springs, feeder roots originate from these as well.
Feeder roots; These range out from the bracing roots, dividing until they are small enough that we term them "hair" roots, they bring the nutrients, oxygen and water to the tree, send out exudates and harbor mycorrhizae fungi.

Feeder roots in desert trees will spread out and dive deep, looking for nutrients and water,

Tom Connolly wrote: There are some plants that are considered to be marginally compatible with desert regions.  It seems that if they can be started - and nursed along for a couple of years - they will take care of themselves.  Can trees be started in a green house to encourage this process and then be transplanted into soil? I have seen root structures from green house grown plants that are longer than normal.  It is probably trees and plants with big tap roots that would benefit from this.

Answering this mostly based on my own experience and not on research, so much...

In my experience, it'll greatly depend on the desert in question and the location IN the desert (from larger areas to small microclimate areas within a yard).

First, the idea of being 'marginally compatible with desert regions' greatly simplifies the concept of desert regions, you know what I mean? One would need to look at what the extremes of a desert are. I think the more extreme the desert is, the less likely marginally compatible plants will succeed there. The deserts that get 2-3 inches of rain a year are less likely to work for these plants than those that get, say, 10 inches of rain yearly.  A marginally compatible plant might be just fine in a desert with an average of 80 F summers could dry up and die in a desert with the same rainfall but an average of 100 F summers.

I live in a desert with the 100F average summer temperatures, and it is very, very rare that marginally compatible plants have succeeded here without constant help. When they do, it's typically because they are in a special location (like the 100 year old pomegranate tree that wild seeded down in a canyon with cooler temperatures and significantly more water than the majority of the desert around it.). It is just so brutal here that even marginally compatible plants often won't cut it, you know?

At the same time...that special location can make a difference. I have some greek oregano that I transplanted, nursed along for a year, then forgot about because it was in a side location out of the way.  Some allysum grew them and covered up the area where it was. Well, that area has some extra shade, and some extra water collects there naturally, and the dead allysum kept the ground shaded, so that oregano just started growing along and was unwatered for 2 years, not a problem at all. I water it not occasionally to make up for taking leaves from it, but it does not seem to need any watering, as long as I leave dead matter on top of it, shading it from the sun.

re: the green house - perhaps it'd work? In my climate, there is such a huge difference in leaf shape and size between plants grown in sheltered locations like greenhouses vs. those grown out in the sun that sometimes you literally think you are looking at two different species. Withstanding the heat and lack of humidity here is such a major burden that leaves from green house plants aren't up to the task. Obviously that would change over time, but a plant that was raised outside a greenhouse would likely have a much easier time adapting.

Tom Connolly wrote:Would it be better to use a biodegradable material to make the long pots for the trees - at some point, just stick them in the ground and within a few months the pot has disintegraded?  It is not that difficult to make such things by hand.

My one thought would be that you'd need to check out the specification of the biodegradable material the pot is made from. At least in my desert, some material that is supposed to biodegrade, well, doesn't. Usually because the material turns out to need a certain amount of water to help along that biodegration, and we don't have it.  So making sure that this isn't an issue with the pots might be important.

Try something like a Growasis Waterbox.

The issue with the different leaves in a greenhouse may be less of a problem with deciduous trees, I think.  Here we try to fall plant or at least earlier spring plant trees so they develop roots during cooler weather. Usually the trees are still dormant, or going into dormancy. I think (no experience here) that the tree would leaf out with the appropriate leaves in the new location.