Saturday, May 9, 2020

Quercus Rubra #1 - Northern Red Oak

Quercus Rubra - Northern Red Oak

This oak was growing in the ground next to my fence. I liked the kink in the trunk and the taper that the tree already had. I left it in the ground last year, as I knew that digging it mid summer would have killed it. I decided I would dig it and pot it this spring as the buds were beginning to swell, right before leafing out. Early April of this year I potted the tree. By the end of the month, it's first buds had opened and began leafing out. I knew I had some decisions to make with this tree. There was a thick branch crossing mid-trunk. It had been cut back in the past causing the two side branches. I also needed to hope roots regrew from the cut tap-root. There were no branches low as well. The kink in the trunk was now looking truly weird, with a sharp angle that jutted out to the left. The more I looked at it, the more I decided it was a flaw in the overall style.

The tree grew through the spring and fully leafed out quite nicely by mid-summer. By mid June, the tree was growing nicely, with several pushes of foliage growth, but no evidence of growth down on the trunk. I decided to attempt to wire the branches up top at this point to try my hand and getting some different angles off the trunk to potentially grow the trunk into. Having not decided on the final style for the tree at this stage, wiring the trunk away from each other and into the sun also afforded the leaves a chance to all get as much sunlight and growth as possible. I covered the soil, a formula of 100% Napa 8822 Diatomaceous Earth, with sphagnum to keep some moisture in the pot. I fertilized throughout the summer occasionally with 14-14-14 Osmocote slow release fertilizer.

Towards the end of the summer, around August, I began using a small amount of water soluble solid fertilizer with each watering when I felt that the slow release was not giving me the healthy growth on the oak. I used the leaves on my Alder as a reference point for this. Because Alder is a nitrogen fixing tree, which can produce it's own nitrogen, I can compare how green it's leaves are to other trees to determine if trees that should have dark green leaves are getting enough fertilizer. This tree wasn't. After beginning the new regimen, it's leaves began to green up. This tendency can help gauge other trees as well so an Alder is a good tree to keep in a collection for this reason.

Today, I captured some of the tree's early autumn color setting in. Just like fully grown trees, bonsai will turn colors with the season. Here, you can see some of the red coming into view. Note the small front branch low on the tree. After I removed the branch from the middle of the tree that I didn't like from the beginning, the tree began activating buds lower on the trunk. This branch grew from a bud in the perfect location. Next year, I will allow this branch to build up some strength by pruning the upper branch that is most vigorous. Eventually, I will chop the whole tree back to this low branch to grow out from that point. Currently I do not know the age of this tree. I expect it to be around three or four years. I will know for sure when I do my first cut back to the low branch - I will be able to count the rings on the trunk at that point.

Here, you can see the smaller leaves turning the distinctive red which Red Oak is named after. Note the size of my finger; oaks are notorious for having leaves which do not reduce well however I have had several buds on this tree push leaves that were smaller in size once in the pot. Red Oaks have different growth habits compared to White Oaks. You can tell the difference between the species by the type of lobes on the leaves - Red Oaks have pointy lobes while White Oaks have rounded lobes. White Oak species do not require a stratification period for their seeds to germinate while Red Oak species do. I have not seen many people with Red Oak bonsai so this tree is an experiment but I am pleased with this leaf size. If through ramification the leaves naturally reduce to this size, this will become a very nice tree to train.

On the trunk, there seem to be some more latent buds which have appeared. Hopefully next spring, I will have more low branches to work with on this tree and I can work on getting a good start on developing some long-term branching to grow out. I also am interested to see how the bark comes along next year. At the moment, this is one of my best prospects for a nice potential bonsai. There is another one growing in the back by the shed so I may have a second by this time next year.


 At the end of 2019, this was the state of the tree, with it's nicely colored, though large, leaves. The lowest left branch will likely become either the next leader for the tree (a branch selected to continue to the trunk after chopping the top of the tree off) or the first low branch. The major flaw in this tree is still the awkward kink in the trunk just below the split into two branches. The upper branches right now are simply to power the tree until some better branching develops lower on the trunk.

There were dormant new buds on the trunk of the tree all over, so I hoped that these buds would become further low branches, and allow me to begin to make decisions on the future long-term styling of the tree. The top of the tree is always strong, so being able to remove the top of the tree at the right time allows the lower parts of the tree to become strong. This is the process by which a tree is kept small, and compact, and how leaves reduce to smaller sizes.

Close up of the lower part of the trunk with the left low branch. If you look closely just above that branch's origin point on the trunk towards the right, you can see another latent bud which hopefully would leaf out in the spring.


















With the buds swelling in early April of 2020, I went ahead and took the opportunity to work on this tree's roots and repotted the tree at a slightly different angle.

Pictures show the process. Any questions on this process I can answer in comments.

Left: the root ball after taking out of the pot. A lot of fine roots present. This is my first time see the growth on this tree's roots. Every species has slightly different roots.

Right: A worm had made the pot's root ball home through the winter. I put it back in the garden.
Left: I removed the soil and raked the roots out the best I could. There were a lot of good roots towards the first curve at the base of the trunk.

Right: I went ahead and cut off the majority of the remaining tap-root, since I had enough strong root mass above this point. A flat root ball is important.
Left: After removing the roots I did not want to keep, I still had a good amount of fine roots to allow the tree to grow strongly. The tree is forming a decent radial root system.

Right: The new planting angle. It looks much more interesting than the perfectly vertical trunk in the original planting.


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