Questions on Roots Demystified answered by Robert Kourik and more

Hi I'm Robert Kourik and I am the author that will be answering questions for the book promotion this week. My book for the promotion is Roots Demystified, change your gardening habits to help roots thrive. I am looking forward to this!

Howdy Robert, so glad to have you here with us!

Thanks Miles. I'm looking forward to an exciting dialogue.

Hi Robert,

I've got a native pawpaw patch down in the bottom of a ravine (rich clay gravel, those trees generally produce fruit every year, but it is heavily wooded and mostly shaded by large hardwoods. Anyway, I've tried unsuccessfully a couple different years to transplant some young trees out of that patch, and move 'em up on top of the hill, where they can get more sunlight and closer to the house. (I have installed a wickingbed type ditch for the latest batch of pawpaw saplings to live near)

My problem is I'm not having much success, especially with the larger ones (6' tall, stem about 1/2-3/4" thick). I've tried to be really diligent about getting most of the tap root, but after a foot-18" deep the tap root tip gets broke. And I try to get as much (2-3') of the 'suckering' roots that usually shoots off toward (from) a larger pawpaw tree. I am rarely finding the 'hairy' feeder type roots. I'm also doing my transplanting at midsummer, because that is what the Univ. of Kentucky (internet site) has suggested. I also transplant the roots 'in firmly', anchoring the roots fairly tight in dirt, and then finish back filling till they won't easily pull out, & self supporting/standing. I don't fertilize, just water (stored rain) for a couple weeks.

Is it mandatory for pawpaw tree survival to have the very tip of the tap root intact? And any other suggestions that might be helpful, I've also been known to transplant about the same size dogwood & large spicebush, even tho I transplant immediately, I'm not very successful, even tho I follow lateral roots 6' or more, trying to find those hairy feeder roots at the tip. Normally I wouldn't even attempt to transplant larger trees, but they are growing in the 'old roadway' and I would rather try to save them than just wasting them by getting run over with the truck.

Maybe I'm just too rough with them. Little dogwoods, spicebush, & pawpaw (up to 2' tall) I have pretty decent success. Maybe I need to change my habits, I'm sure if I can keep the roots to thriving, I will have full success.

james beam

Hi James, Alas I live in Northern CA and have never worked directly with paw paws. Most trees with deep taproots don't take to transplanting. Are you doing the attempts bare root in the fall or spring? What I tell people who want to maintain the taproot is to plant a seed. Takes a long time before you can graft, but the taproot will be very well established. The persimmon trees I get bare root in the spring do take to transplanting even though the taproot is broken/cut off. (It's one of the few non-nut fruit trees that likes to make taproots.) Like oak trees and pine trees, both like deep tap roots when young, some trees just don't want to be transplanted. I hope this helps. Robert

Ok on the pawpaw, no big deal, I am growing some extras from seed just for fun~~~but sometimes, I'm the impatient kind~~~.

Yes they are bare root, they never see a pot, but I'm careful to not allow them to dry out, ( been using wet moss while digging/transporting--- but I'm going to try dipping them in a bucket of clay slip to coat the roots, next time) although the larger saplings do take a good amount of time to dig one out, I always install them the same day I dig them. I have been doing the transplanting of the pawpaw in late summer around August, maybe I'll try digging a few just now in December, to see if my success rate improves. I think the soil PH is similar where I'm transplanting into, albeit the moisture content is less on top of the hill (that is what the wickingbed ditch should fix, hopefully).

I would like to have pawpaw growing in the sunshine, expecting better yield.

james beam

James, as I understand it, Paw paw is an understory tree that does not want too much sun. I've seen a number of accounts of young plants failing because they were overexposed to sunlight.

No personal experience here, yet, but there are lots of discussions about paw paws here on Permies.

Oh man, Robert thanks for being here and answering questions. There is so much I want to know about roots I don't even know where to start. Could you briefly state or link a bit of background? It may help me focus.

I'm curious about different adaptive strategies. How root growth often seems to reflect habitat and nitch? Something like that. For instance in my biome. Nettles and bracken thrive in woodland clearings so long as the soil is relatively uncompacted, but when the soil significantly compacted the imported Foxglove seems to thrive. This along with the structure of foxglove makes me wonder if it has a taproot as both bracken and nettle seems to spread mostly laterally. Many of the brambles including trailing blackcap and himilayan blackberry seems to have roots that are vigorous and deep, similar to the root mass your are holding in one of the circulating photos, but seem like therethey are seeking out wet spots (like under rocks or following channels?) rather than trying to go straight down to the water table like a tap root might.

Also in keeping with the permies vlog of the week "roots, the art of fire, and drier lint" can you comment at all on what happens to root systems in a fire? I have seen black veins several feet deep in otherwise unstained mineral soil which I have both presumed and been told are roots left over from fire. Those would be conifer roots. Has me thinking of deep rooted prairie grasses.

Also any comments on how different communities of root systems effect water infiltration?

Thanks for any comment and I'll try and stew on a more focused question or two

Welcome to the permies forum Robert.
I have noticed, over the years, that some trees have one small (short)l root up on the graft. Usually a couple of inches above the main root ball. Should I plant the tree deeper and cover that extra root, leave it exposed or cut the root and plant at normal depth?
Thank you

Hi Landon, So many plants outside of the prairies do not have a taproot. I don't have any drawings in my book of foxglove roots but I suspect, after watching the ones in my garden, they have wider roots than depth. In the prairies roots can go quite deep due to the irregular rains in part. Virtually no plant reveals what the roots are like by looking t the foliage. Horseradishes grows 2-3 feet tall but the roots have been mapped down to 13' deep. Prairie plants are similar with roots many, many feet deeper than the foliage is tall above ground. I have a drawing done by Dr. Weaver in the 1930s of prairie plants (Nebraska) in my book. Check out Roots Demystified published by me. Most trees in many soils and climates have roots many times wider than their depth. Most trees have 50-80% of their roots in the top 18-24" of soil while the roots are often 3 or more times wider than the canopy. Very few trees have taproots. Exceptions are oaks when they are young, pines and most nut trees. An edible tree with a taproot, only if grown from seed, are Asian persimmons. Roots do help us figure out soils. In my experience the common "weedy" ground morning glory (Convolvulus sp.) indicates compacted soils. There is a large chart of plants as soil indicators in my 1986 book Designing and Maintaining Your Edible Landscape - Naturally. I hope this helps. Robert

Hi Diane, Never bury the graft as you probably know. I have had a few apple trees sprout a root near the graft. (Haven't seen it on plums as an example.) Only cover it with soil if it is at least 2 or 3 inches or so below the graft. Also below the mulch as young root sprouts can grow into the mulch. But I think it's best to plant at the level the tree was in the nursery. Ignore the rootlet or trim it off. Robert

Hello and thank you Robert.

My question relates to woody plants, and soil amendments, particularly the so called clay pot syndrome. For those not familiar the idea is that when planting in high clay or compacted soils, roots will have limited growth being trapped inside the hole which was backfilled, especially if that soil is particularly inviting. My tendency would be to start my trees out strong with some biochar compost mix, and expect that healthy roots will break up clay soils when the tree gets large enough. Lets ignore the hydrology of heavy clay soils for this question, and assume the tree is planted in an otherwise ideal situation. TLDR: Is clay pot syndrome real?

james beam wrote:Ok on the pawpaw, no big deal, I am growing some extras from seed just for fun~~~but sometimes, I'm the impatient kind~~~.

Yes they are bare root, they never see a pot, but I'm careful to not allow them to dry out, ( been using wet moss while digging/transporting--- but I'm going to try dipping them in a bucket of clay slip to coat the roots, next time) although the larger saplings do take a good amount of time to dig one out, I always install them the same day I dig them. I have been doing the transplanting of the pawpaw in late summer around August, maybe I'll try digging a few just now in December, to see if my success rate improves. I think the soil PH is similar where I'm transplanting into, albeit the moisture content is less on top of the hill (that is what the wickingbed ditch should fix, hopefully).

I would like to have pawpaw growing in the sunshine, expecting better yield.

james beam

Hey Robert~ thanks for doing this - I plan to check out the book.

James,
We're in the same zone, so perhaps this will help. I only have success with mid-sping (March/April) transplants. Unlike almost any other fruit, pawpaws don't care for dormant transplant. If you could get more than 18" of tap root, it would be helpful - 24" is what we hope to get. If they are native pawpaws, they'll stuggle in full sun. They like far more dampness than full sun would allow even with mulch. We transplant 6'ers, not babies.
Hope this helps.

Yes Matt, clay pot syndrome is real. Since roots prefer to be .5 to 3 times wider than the foliage, no planting hole can support all root growth. The roots must grow well beyond the planting hole. Anything other than native soil causes the root to stay in the hole feeding on the artificially-provided nutrients. The roots are less likely to grow beyond the hole. There are many studies that support the native soil backfill as the best way to go. In fact, in my book I make the argument and recommend always planting on a mound in any soil so as to protect the crown of the root system and encourage the roots to grow beyond the planting area. The roots have to be able to adjust to native soil sometime so why not start them off from day one? But you have to match the roots to the soil. Thus you can't plant peach trees, as an example, in heavy clay soils. The roots aren't "built" for it.

Thanks for your suggestions Marianne. I'll keep working with it.

james beam