The main downside of the amended soil was the root mass was significantly less, even though top growth was sometimes greater in the first years. I’m not sure if that matters as much for pawpaws since they tend to send down strong taproots.
I think your plan to till in the wood chips for the entire planting area to mix them with the added lake bed soil makes sense, and would be in line with the recommendations in those planting guides.
Not for the trees grown in clay, maybe you are talking about the bushes and other plant studies I did not read and even then the author seems to make huge generilizations and conclusions. Especially at the end when he state’s it’s not economically worth it, even those his data shows it has obvious improvements in all the trees.
I’m talking about the same study where you posted a screenshot of the growth rates (test 4 from the second to last link I provided). They said this:
Amendments resulted in significantly smaller root systems.
and this is in the discussion right next to the table you posted:
For Test 1, azalea had significantly more root mass in clay than amended soil, and 2/3 of the holly in amended soil had root knot infestations:
I mean yes some of the plants with amended soil did slightly better, especially dogwood, but some of them definitely didn’t, especially if you focus on the roots rather than top growth.
I’d say at best it’s a mixed bag that might sometimes help, but I think all these studies reached similar conclusions that it’s not generally worth the effort because it probably won’t help and might even make things worse. While you can always cherry pick certain data points that contradict their conclusions, the data as a whole seems to support what they say it does, at least to me.
data clearly shows that certain bushes and trees grow better in amended soil and others grow better in clay. if I was growing azela’s I would use clay, I’m not growing bushes so I looked at test #4 which was about trees and all the trees did better amended in table 5.
not cherry picking data the author says it himself that not all plants are the same and that some grow better in different soil.
i agree it’s a mixed bag and one should look at what kind of plant they want to grow and the soil they have and look at the tables for that specific plant. at a minimum the conclusions should of been divided into the 4 test groups, instead it was just a poor misrepresentation of the data. . This study used georgia clay soil which is similar to mine.
Ok, then look at the chart you posted and compare unirrigated amended soil with unirrigated native clay. Notice which one does better for every single species? In some cases drastically so? That alone should speak volumes, since their irrigation was probably much more precise and controlled than most home or even small scale commercial orchards.
So, if you are planting in your clay and don’t plan to use irrigation that’s controlled by soil moisture sensors and such, then maybe your results will look more like their unirrigated results.
Every study says irrigation is more important than any other factor. I plan to use irrigation because the data backs that up
Also i know clay holds water better than any other soil type so it is not surprising that amended clay would hold less moisture
Keep in mind that some folks in poor soil areas (high salinity, poor drainage etc) just mound up soil in the area they are planting the tree. I think that once established your trees will thrive even with a high water table as long as it is relatively well drained on the surface. Pawpaws do love water, just not living in a wetland. There is a reason their taproot can grow two feet the first year.
There are several wild paw paw groves where I live and the few I’ve visited are all by a creek or pond, one looks like it gets flooded for a day or longer a few times a year. I have no doubt they will grow in clay soil just trying to get them to grow as fast as possible
I live near Annapolis, Md and planted six paw paws. We live on a steeply sloped plot, over an area that used to be a sand pit. I am surprised that OUR paw paws seem the grow with little or no help (30-40% of the trees I plant have died). I have stopped watering my plants since my wife told me that using our water-softened tap water probably kills more than feeds. The roots seem to find their way down the hill (there is a small stream at the bottom of the hill) and into the grove of shady trees. My initial hole was 3-4 feet in diameter and about 2 feet deep. My point is that paw paws, at least for me, seem to be a very self-sufficient tree.
That pawpaw looks very healthy. They are not easy to grow like that here. We can grow blackberries and pears very easy.
