When bonsai exhibits come around, bonsai enthusiasts love moss. They drive around town with their eyes on gutters and puddles in hopes of finding patches that can be scraped up and used as top dressing for their trees. But when moss grows into pine bark, the story changes. The goal is to find a way to stop moss from deteriorating delicate bark found on pines, spruce, cedars and the like.

Too much moss on the trunk – the bark is in jeopardy

On a recent visit to California, Akio Kondo made a suggestion for stopping moss – dish soap. He suggested mixing one part dish soap with 10 parts water and brushing it directly onto the moss.

Soapy water

Will the soap hurt the tree? Will it discolor the bark? I don’t know.  Does it actually kill the moss? Yes. I gave it a try using a fairly mild dish soap. The 1:10 mixture I used browned a bit of the moss but not the thicker patches. I found I needed a stronger mixture to kill more of the moss.

Painting soapy water on mossy pine bark

A thick patch of moss – this bit proved stubborn

Like so many things in life, prevention is key. Stopping moss before it takes hold is far easier than stopping moss that has covered the bark. A lot of moss grew on my trees this spring and summer when it was cool and cloudy, but the moss has slowed down a lot in the past couple of months as the sun finally came out. As the days get shorter, I’ll be sure to keep some soap close at hand.

I brought the white pine below to an Akio Kondo workshop this past August. The tree looked much like it does now but the old needles had yet to turn brown. New growth had appeared much like it had the year before, and I had prepared to spend an afternoon wiring the tree. Kondo took one look and said nope, the tree’s too weak. He suggested I water the tree lightly, every other day at most, and wait until the following year to cut or wire the tree. Kondo wanted to see vigorous new shoots before stressing the tree with cutback and wiring, and the new growth wasn’t exactly vigorous.

What to do? Not much. Now that some of the old needles have turned brown, I removed them by running my fingers through the foliage and put the tree back on the bench until next year.

White pine – October 2011

Shoot with old needles

Old needles gently removed

I took care not to remove all of the old needles, just the ones that fell away as I combed the foliage with my fingers. Typically fall is a good time to remove last year’s needles on strong white pines, but it’s best to leave weak trees alone until they get stronger. The photo below shows both first and second year needles, separated by a small gap along the branch.

Same shoot from below – first and second year needles remain

Loose needles removed

I expect that more second year needles will turn brown and fall away as the weather cools, and I’ll likely remove these around the end of the year.

I find mid-summer to late fall to be an interesting time of year in bonsai. It’s a good time for the little tasks – the maintenance work. In cooler seasons, I can bring one or two trees to a workshop that will keep me busy all day. This time of year, I tend to load up many trees and spend just a few minutes with each. This month was no exception. My winterberry, for example, has been growing vigorously, but big cutback isn’t scheduled until the end of the growing season. For now, I’m content to remove a few unnecessary branches and wire the new shoots.

Winterberry

Late spring is a good time to work on satsuki. My small azalea has grown dense since spring so I thinned out the new shoots.

Satsuki azalea

My Yaupon holly has budded back wonderfully this year. Like I did for the winterberry, I removed a few unnecessary branches and wired the new shoots. Major cutback will come later.

Yaupon holly

Not everyone in the workshop busied themselves with such mundane tasks. Here is one of the three ficus that received a basic styling while I was busy with my trees. What a fun project!

Ficus

I also had a chance to partially defoliate my trident maple. I’d hoped to do this work a month ago, but August has been cool and my trees have been growing slowly. Instead of removing all of the tree’s leaves this late in the season, I removed a lot of the growth at the ends of the branches and all of the big leaves.

Trident maple

New leaves revealed after removing the large leaves

Half-way done

Partial defoliation complete

Watching the interior shoots make slow progress has made me wonder about taking a more radical approach next year. Although I have plenty of time to consider what I’ll do with the tree next spring, I’m already looking forward to seeing what will happen.

I recently learned, a bit late, how to treat black pines that were decandled in fall – see “Fall decandling, year two” for details. After decandling the tree, I took the opportunity to wire it in a workshop with Akio Kondo. After reviewing my wiring, Kondo asked if I had a toothbrush. Too soft, he said. I offered a nylon brush with bristles I’d shortened for cleaning juniper bark. Perfect. Kondo took the brush and began gently brushing the tops of the branches. He says the gentle stimulation will encourage new buds.

Brushing the bark

I quickly brushed the remaining branches and began looking forward to learning what will happen when the tree buds out next month.

The wiring, Kondo noted, is not for styling. It’s sole purpose is to expose the interior branches to the light. A few years down the road, when new shoots become large enough to wire, it will be time for a proper styling.

After wiring

At this point, I’m simply hoping for enough warm weather to coax some summer growth out of the tree.

Last fall I decandled two Japanese black pines a few months later than normal – see “Fall decandling” for details. New shoots appeared soon after I decandled the trees but they stopped growing during winter. In spring the new shoots became vigorous. At this point I realized I didn’t know the plan for the second year. Fortunately, Akio Kondo was due for another visit.

Earlier this week, Kondo – a Japanese bonsai professional in town to teach and work on client trees – visited our monthly Bay Island Bonsai meeting and gave a critique. I brought both pines I’d decandled last fall. Kondo’s first question: why didn’t I decandle the trees this year? I pleaded ignorance. Turns out it’s very important to decandle the trees at the regularly appointed time the year following the fall decandling. For Northern California, that means the ideal time for me to decandle these trees was a few weeks ago in mid-July. Because the trees are strong, we decided to decandle them anyway.

Kondo says not to expect much immediately after decandling trees in fall – it’s in the second and third years after fall decandling that we can expect new buds to appear.

Kondo sizes up the tree

Bonsai professionals who studied at Kihachi en – the bonsai nursery of the late Kihachiro Kamiya – tend to work on pines with tweezers in their right hand and scissors in the left. It’s a good system once one gets used to it.

Kondo decandling

Fall shoots differ a bit from spring shoots. Spring shoots have a “neck” at the base, as Janet put it – a pale green area from which no needles grow. Fall shoots seem to grow directly from the branch with needles appearing all the way to the base of the shoot. Both shoots are decandled the same – the cut is made just above the base of the new growth.

Fall shoots

Decandled branch

Decandling complete – one more tree to go

Kondo only took a few minutes to decandle the small pine. His critique of the tree included a suggestion I don’t often hear. He said to thicken the middle part of the trunk. The base is a good size for the style but the rest of the trunk is skinny. By thickening the mid-section, I can improve the tree by producing better taper.

The second tree was more dense than the first.

Black pine, August 2011

When Kondo saw the second pine on the turntable, he suggested that I do the cutting and he do the supervising.

Kondo and I considering a cut

For time’s sake, I used the scissors in my right hand and pulled the decandled shoots away with my left. It would be generous to say I worked at half Kondo’s speed.

Decandling

Kondo looking over my shoulder

By the end, Kondo was “helping” from the sidelines.

Still decandling

When the decandling was complete, I noticed I’d removed the bulk of the tree’s foliage.

Decandled shoots

Kondo followed up by cutting back some of the more vigorous shoots to encourage new interior growth.

Summer cutback

I’m curious now to see if more new buds will appear later this year or early next. Either way, I’ll be sure to decandle the tree on time next summer.

Greg recently brought a crape myrtle to a Bay Island Bonsai workshop. The tree has a large trunk and good roots. It also has a big first branch. Boon recommended removing it.

Crape myrtle – front

Crape myrtle – left side

Crape myrtle – right side

Because the branch was so large, Boon recommended making the cut in stages. Greg could cut most of the way through today, and complete the cut next year.

Proposed cut – left side

Proposed cut – right side

Removing the branch in stages speeds the time it takes for the wound to heal over. It’s also less stressful for the tree.

Making the cut with a sharp saw

Cut complete

After making the cut, Greg cleaned the edges of the cut with a grafting knife. Even sharp saws tend to leave rough edges. Cleaning the cut with a grafting knife will help the wound to heal quickly.

Cleaning the cut

After cleaning the cut, Greg covered the wound with cut paste. In one or two years, the cut will have healed significantly and the rest of the branch can be removed.

I first learned about this technique in Japan at Ebihara’s garden. Here is a photo of a Japanese maple undergoing a similar treatment.

Healing a large wound on a Japanese maple

You can’t have too many branches on ume – or at least I can’t. Getting ume to ramify has proved difficult for me. I made several grafts this year and fortunately most of them took. See “Ume – cutback and grafting” for details about the grafting process. My job now is to help the scions develop. To do this, I cut back the branches onto which the scions have been grafted.

Ume – before cutback

Ume – after cutback

I’ve left the grafting tape in place to keep the scions secure while they are fusing. If the branches continue to grow well, I’ll remove the tape in fall.

Grafting tape holding scion in place

The following photos show the new scions and the original branches onto which they have been grafted. The new shoots look a lot like the old shoots – why have I bothered? The new shoots bear fragrant white flowers – the old shoots, double pink.

Scion on left, original branches on right

Original branch on the left, healthy scion on the right

While I worked on the ume, I noticed both large and small junipers taking shape. Jeff brought in the big juniper below for a tune up.

Getting the tree into place

Prostrata juniper

A much smaller juniper was showing some real progress. The shari had been added to make the trunk more interesting and the branch pads were developing well, showing off the shimpaku foliage to great effect.

Shimpaku

Shari – note how the curves exaggerate the natural flow of the trunk

Branch pad showing good ramification

While I was inspecting the shimpaku, Boon called me over to witnes a sap bubble that formed where a shoot was cut on a black pine. Apparently this happens occasionally on hot days.

Sap bubble

Decandling is a great technique for improving ramification or for maintaining it. What little ramification my red pine forest has can be attributed to a few years of decandling. I don’t currently have any plans to further develop the trunks in this forest, so the branches are getting all of my attention. Here is the group planting before decandling.

Red pine forest – June, 2011

Top 1/3 decandled

2/3 decandled

Completely decandled

In addition to removing the spring shoots, I removed some extra vigorous branches to better balance the tree. The shoot below is quite vigorous – more than I want for this bonsai.

Vigorous branch

The branches below are better suited for development into branch pads.

Desirable growth

Where extra-vigorous shoots were crowding out more refined growth, I removed the vigorous shoots.

One of these shoots is not like the others

Extra-vigorous shoot removed

As I worked, I found a few anomalous shoots like those below. They weren’t spring shoots, but they weren’t exactly summer shoots either. Where did they come from?

Mystery shoots

About two months ago, I thinned these trees and shortened some of the candles – see “Thinning a red pine forest” for details. On one or two occasions, I accidentally broke the candles before they had time to develop. It was as if I “de-candled” these branches on the early side. The result of these mistakes are the strong shoots you see pictured above. As these shoots would continue to develop ahead of the properly decandled branches, I removed them to maintain balance.

Mystery shoots removed

After removing all extra-vigorous shoots and plucking needles from some of the more dense areas, I wrapped up my work for this season.

Decandling complete

This forest is another good candidate for wiring this fall. Once the branches are in place, I plan to repot the group in a slightly smaller pot.

I’ve received a lot of questions about decandling since I started writing about it. The basic idea is simple – we decandle pines to replace vigorous spring growth with less vigorous summer growth. There are, however, a number of variables to consider, from timing to needle plucking to after care. The best way to navigate these details is with an experienced teacher. If a good teacher isn’t available, I recommend experimenting – preferably with a tree you consider appropriate for experimentation. (For details about some of the variables to consider when decandling, see “Decandling secrets revealed!“)

The first time I decandled a pine on my own, I had an idea of when and what to cut, but was less clear about how the new growth would turn out. I watched the summer shoots develop very closely that year and ended up learning a lot. I’ve still a lot more to learn. Here’s what the process looked like on one of my more developed – though still young – pines this year.

Japanese black pine – June 2011

Vigorous spring shoot

Spring shoot removed: note that I left a tiny bit of the new shoot – this is where the summer shoots will emerge

Needles thinned

Five needles and a short stub remain

After decandling and needle thinning

The tree is more than a bit straggly at this stage. As the summer buds have begun to appear, I have to wait until fall before I can wire the tree. What does a recently decandled pine look like after a great wiring job? I recommend Peter Tea’s recent photographs of a 100-150 year old pine for an answer. See his Aichien Journal for the story.

The progress continues on a Japanese black pine I’ve been working on since digging the tree from Lone Pine Gardens some years back. This summer’s work consisted of decandling, thinning a few needles, and reducing the two temporary branches at the top of the tree.

Japanese black pine, approximately 18yrs old – before decandling

After decandling and cutback

The straggly branch at the top left is keeping the trunk alive until a couple of grafts take. I don’t need much growth here, but I want to keep the sap flowing past the grafts. The straggly branch on the right is part of the new apex. I’m letting it grow until the apex is closer in size to the trunk. Once enough grafts take and the apex has reached adequate size, I can remove these branches and actually get an idea of what the tree will look like as bonsai.