Simplified Protocols for Yamadori Collection, Aftercare, and Initial Bonsai Training - A Honeysuckle Raft Case Study.

            In preparation for the 2nd Annual CBS / Columbus Recreation & Parks Department Invasive Honeysuckle Yamadori [Wild Bonsai] Dig event, I wanted to put to words a very simplified protocol for how to take a freshly dug yamadori from the forest and how to begin to train it as a bonsai tree. Obviously, the speed of development varies based on the species and health of the tree and some steps may even occur at seasonally different times especially if you are in a different climate than me here in USDA Hardiness Zone 6, Ohio, USA. Noting that these exceptions are bound to hit you at some point, let this be a starting point and take it for what it's worth. To exemplify that protocol, let's follow the development of my extra large honeysuckle raft yamadori which I rescued from culling in a local Columbus park at last year's first invasive removal collaboration. You can read about our previous experience hosting that event here, and you can see other examples of renowned honeysuckle bonsai here. 

Sections:

1. Event Description - 2nd Annual Columbus Bonsai Society / Columbus Recreation & Parks Invasive Yamadori [Wild Bonsai] Dig
2. General Protocol for Temperate Deciduous Species Yamadori Collection
3. General Protocol for Yamadori Aftercare
4. General Protocol for Initial Bonsai Training - First Repot, Early Pruning, etc.
5. Honeysuckle Raft Case Study
1. Spring 2022 Digging
2. Fall 2022 Pruning
3. Spring 2023 Repotting + Pruning
6. Announcements
1. I officially applied with the state of Ohio to start a nursery. Contact me to enroll in my first workshop on Tanuki! See details here. The second workshop will be on Sunday, 4/23/23 from 12pm-3pm. Contact me if you would like to request an additional date.
2. 4/15/23 - 2nd Annual Invasive Honeysuckle Wild Bonsai Dig with CBS and Columbus Recreation & Parks @ Castro Park. This is a free event. Sign up here.
3. 4/16/223 - Columbus Bonsai Society Meeting - I will be presenting on the ins and outs of digging Yardadori/Yamadori/Wild Bonsai. All are welcome. See event details at www.columbusbonsai.org.
4. Seeds are available here.

My extra-large honeysuckle yamadori raft, now freshly repotted into its first training bonsai pot.

I. Event Description - 2nd Annual Columbus Bonsai Society / Columbus Recreation & Parks Invasive Yamadori [Wild Bonsai] Dig

            Although invasive plants can be the bane of conservationists and native plant lovers, in their native range their intrinsic beauty motivated their original use in landscaping. In the case of the invasive honeysuckle, one can enjoy their pink and white flowers, and red berries can make, and their indestructible nature makes them a great source of free and low-risk plant material for beginner bonsai artists (see examples of honeysuckle bonsai here). Transplanting trees for bonsai is a risky business, so what better to practice with than trees that are nearly indestructible and easily replaceable in the worst-case scenario?! Furthermore, their invasive properties are easily limited when the plants are container grown as fruit can be pruned off before getting into the environment. Due to these factors, the Columbus Bonsai Society is proud to collaborate with the Columbus Recreation and Parks Department for the 2nd Annual Invasive Yamadori [Wild Bonsai] Dig. We welcome all who are interested in bonsai to join us at this event. Attendees will get to bring home free plant material, are entitled to 3 free CBS Newsletters to help inform your first steps as bonsai artists, and are always welcome to bring the plant to a CBS meeting for advice. Find the monthly meetings at www.columbusbonsai.com.

This year the event will be on Saturday 4/15 from 9am-12pm at Castro Park. Sign up here.

II. General Protocol for Temperate Deciduous Species Yamadori Collection

For a broad overview, the process of turning wild plants into bonsai goes as follows.

1. Learn to identify invasive honeysuckle or other species of interest in your area. Generally, invasive honeysuckle are ubiquitous throughout the eastern US and are a mix of 4 species as I discussed in last year's articles. These species have common traits - white flakey bark, leaves that emerge early, white flowers of distinct shape, red berries, and they tend to grow upright as small trees or shrubs. Do NOT confuse them with the vining honeysuckle species which are native. See here for more information. We will review identification on-site at the event.
2. Find interesting specimens in the forest. Bonsai can be made of woody plants of any kind and size as long as you are able to dig and lift it out and put it in a pot. Just note that smaller plants are far quicker to dig and survive much more easily! Attractive traits for bonsai include movement, especially in the lower trunk, deadwood scars that show age, taper in the lower trunk thickness, attractive surface roots/nebari, and useful branching. See the discussion of wild honeysuckle and their attractive qualities/potential future designs here for examples.
3. Chop off unwanted long, straight, taperless sections of the trunk and branches which will not be used in the future design. Honeysuckle and many other deciduous species backbud easily so it is okay if you're left with a bare trunk.
1. Many deciduous species are also tolerant of trunk chopping to prepare trees and induce backbudding while leaving them in the ground in your forest. You may want to try this out if you have an area you return to year after year. I'll share more on my results with this later.
4. Dig a trench around the tree and pry underneath the tree. Sever large roots until the tree is removed. Fully removing the root system is the only herbicide-free method of eliminating invasive honeysuckle from the environment. 
1. Spring is the ideal time to dig for survival of the plants, but some species can survive summer digs too. In cold, snowy places, fall digs are possible, and success is improved by the use of a heat pad or keeping the roots above 32F all winter with a heated cold frame. Fall/winter digs are also done in warmer climates which rarely see snow. There's lots of regional variation here!
2. For some species, if there is only a taproot and no fine feeder roots near the trunk, it may be unlikely to survive the dig. It's better to leave those trees alone and save your time for other more fruitful trees. A ground layer, air layer, or other "root enhancement" type method may help you make use of these if you are flexible on the removal timeline.
3. For exceptionally large trees which have a higher failure rate following transplantation, you may want to get an exceptionally large rootball or do a partial trench of the tree in prior years to improve your success rate. I am still experimenting with this as well. Luckily, this is not needed for honeysuckle!
5. Wrap the roots in a trash bag (durable black contractor bags are preferred!). Electrical tape is also useful to tightly bind the rootball so there are minimal air spaces between the bag and the roots. This helps keep the moisture in. This is a temporary solution to get the plant home.

III. General Protocol for Yamadori Aftercare

1. Pot the plant into a container it fits into as quickly as possible after the dig (within a couple days max). Minimizing this time minimizes stress and maximizes healing. Some extra root pruning may be done but not too much or it may not survive. Fine roots must be left on the tree when potting as they are the engine of your tree's survival! Honeysuckle won't be picky, use any potting soil you have available, but bonsai soil is preferred when you get more advanced or for older trees and more delicate species which are challenging to transplant.
1. This part can get nuanced for advanced practitioners. I'll just leave you with the idea that 100% pumice is the preferred bonsai soil to surround freshly dug rootballs as this allows lots of air into the pot and promotes lots of fine root development. Perlite is allegedly comparable, cheaper, and more widely available but my own experiments with this are underway so I cannot say yet. Try for yourself and let me know!
2. Large trees can be put into custom-built wooden pots. You could also leave them in the black contractor bag if you used the durable kind and poke holes throughout for water and air to get in and out of the rootball. I have done this with success, but I can't say that it is better or worse. I'm still collecting data on this method but it is VERY convenient (on time and cost), and my teacher Dan Robinson has used this method with success for years.
2. Leave the plant in the shade while it recovers from the dig for at least the first summer due to the stress of heat and water loss. Do not fertilize for the first few months after digging either as excess ions from fertilizer can dry out sensitive new roots and kill the tree's recovery. Water regularly. Keep the soil moist but not soaking wet.
3. Water regularly and fertilize lightly throughout the summer. Honeysuckle should grow abundantly to continue recovering; other species recover much more slowly. Survival is only assured after 1 year. Do not prune unless you are confident in its survival.
4. In winter, insulate your roots from and protect them from dry winter wind. This is the same recommendation as most bonsai, but especially true for sensitive freshly dug plants! You will still need to keep the soil moist as it can dry out even in winter.

IV. General Protocol for Yamadori Initial Bonsai Training

1. If the plant is obviously healthy, you may prune the plant back in the fall to get rid of unwanted branches and to shorten the branches you want to keep. Plants that did not have much new growth or new backbudding are not yet vigorous and should not be pruned yet! Wait until you see signs like this.
2. If the plant is obviously healthy, you can repot the tree in the first spring after collection to reduce the rootball and plant it in good bonsai soil. A partial bare root is the conservative method which is least risky for the health of the tree, but on small or young specimens, or certain species, a full bare root may not harm the tree and allows you to most quickly get rid of the native soil which is overly water retentive. Again, save the fine roots as much as possible. The first repot is a very delicate operation on an old yamadori!
3. Enter a cycle of periodic pruning and wiring of the branches to fit your design of choice. Again, do these mainly on healthy trees. If the plant is recovering from a bad year, it may help to let it grow out and prune it back again later!

V. Honeysuckle Raft Case Study

A. Spring 2022 Digging

            See last year's post with pictures and descriptions here.

B. Fall 2022 Pruning

                The tree grew vigorously without pruning all summer! Hence, I pruned it back to some future branch/trunklines in the fall. You can also see here and in the next section that I left the large and oddly shaped rootball in the contractor bag for the first year with no ill effects on the tree (as discussed in Step III-1-2).

C. Spring 2023 Repotting + Pruning

            The tree leafed out early while I was still busy digging new yamadori, so this repot is a bit late. Luckily, the indestructible honeysuckle gives you some leeway!

You can see there's a long stretch on the left which I did not use in the design. It was too long anyways! That also had roots and will become a separate tree.

One potential front. The deadwood has appealing sides on both directions. Eventually, I'll need to get it into a thinner pot.

Nice hollows! Aka "uro" in Japanese.

Hollows and deadwood from the other end.