After spending time working on my 2 Japanese Maple trees, and also reading up on pruning Japanese Maple Trees, I realized that there was a glut of serious entries on the subject of pruning these beauties.  Typical blog or articles on the topic typically say, “Let the Japanese maple just grow, and weed out the excessive growth”.  That really does not suffice on pruning this beauty, Unless you really want a simple oval shaped tree.

The Japanese Maple has some unique characteristics, which can make the tree really stand out as a specimen plant, if pruned properly.  My way of thinking was, where better to learn about pruning the Japanese Maple trees, then the Japanese?

With that in mind, I read up on Japanese Niwaki principles, specific to the Maple.  These are my pruning rules for the Acer palmatum, heavily influenced by the book: “Niwaki: Pruning, Training and Shaping Trees the Japanese Way” by Jake Hobson.  But the rules have been adjusted for better understanding, and Western Gardening practices.  But also, updated based on my own limited knowledge of pruning my own trees.

Pruning Rules

Glossary of Pruning Terms

1. Horizontal Branch – A branch growing horizontally, or even slightly upwards (to 45 degree).
2. Vertical Branch – A branch growing 45-90 degrees upwards.
3. Epicorm Growth – This is growth stemming from the center of the tree.  It is also called a branching sucker.  These are branches that are attached to the central root system.  They grow very fast, and move straight up.  If left alone, they can take over the tree, but they are unslightly, and off times, discolored.

General Structural Pruning Rules:

1. Prune for a reason.  Don’t cut any branch, unless there is a reason!
2. Prune for beauty / aesthetics – Make the tree fall into the shape you desire.
   1. Don’t allow the tree to decide what shape it will take, you can control the end result, so use that power for a healthier tree.
   2. It is always to the benefit of everyone, to allow the tree to take the shape it prefers.  So prune with that in mind, but do not allow this rule to stop you from cutting where you need to.
   3. There is a difference between pruning for Health (Arborist), and pruning for beauty.  Sometimes both methods have the same goal in mind.
3. Prune for size: Pruning can be used to control tree size.  A well pruned tree, over the years, can slow growth to 1/2 of original growth speed.Very useful in small gardens.
4. Prune for health: Moderate pruning, utilizing basic pruning principles, will always help the tree.

Pruning the Japanese Maple

Trunk Pruning

1. Prune out epicorm growth – They will take over the plant, and can be unsightly.  These branches can be identified by their discoloration, fast growth, and straight vertical growth.
2. Prune out all vertical growth
   1. Identify your trunks (ie – which vertical branches / trunks you wish to use as the foundational trunks for your tree).  For a Japanese Maple 4-5 is ussually enough for a nice branching tree.
   2. Remove all other vertical branches / trunks.
   3. If you don’t wish to prune a vertical branch for various reasons, then understand that this branch will eventually become a major tree trunk.

Primary Branch Training

The focus here is pruning branches that have grown off the main trunk and secondary trunks.  Don’t worry yet about what is happening on the branches.  We’re only looking at the trunk still.

1. The Japanese Maple has a branching habit, but if you want more branches, then “Top” the tree at a 2 bud node (See diagram below).
   1. The tree will then grow a 2 branch head
2. Prune symmetrical branches – The Japanese Maple Tree has a symmetrical branching structure, where 2 buds will grow, directly opposite of each other.
   1. To create a more natural look, prune out one branch/bud from a pair of symmetrical branches.
      1. If you prune out a left branch, then on the next Symmetrical branch, prune out the right branch.  This allows growth to be even on both sides of the trunk.
3. Prune vertical branches – Remove all vertical branches stemming from the trunk.
   1. The Japanese Maple Tree has a habit of producing a horizontal branch, then a vertical branch next.  Keep this in mind when hunting for vertical growth.
      1. Buds all look like they are vertical growth.  So don’t touch buds until after they have grown a little and exposed their growth tendency.
   2. High up on the tree, there will be no Horizontal branches.  This is a misnomer, as 45 degree angled branches, will eventually bend over (with leaf weight) into a horizontal branch.  So the rule of thumb is, lower on the tree, Horizontal branches are growing horizontally.  Higher on the tree, Horizontal branches are growing about 45 degrees upwards.
   3. There may be places, where you can’t remove vertical branches (Or don’t want to).  In those cases, prune the vertical branch down to the lowest acceptable horizontal branch or bud.  The point here is, you are stopping vertical growth, and leaving a horizontal branch, ensuring future growth is moving horizontal only.
   4. When done properly, you will end up with a Japanese Maple Tree that has strong vertical lines in the trunck and secondary trunks, and all branches wil be moving horizontally.  There will be no or few crossed branches stemming from the cross meeting of a vertical branch and the branch above it.  This promotes health via: More air and light inside the tree structure.

Individual Branch Training

Now, Moving from the trunks, work on each branch individually.  Start from the bottom of the tree, and work on each branch individually as you move up.

1. On each branch, remove any vertical leaf or branch.
2. Remove opposing symmetrical branches.  Ensure that as you do this, the branch has even growth.  If you have 5 branches pointing left, you try for 5 pointing to the right (or at least 3-4 pointing to the right).
   1. The only place this is not the case, is symmetrical up/down branches.  In this case, you remove all vertical (upward branches), and leave the down facing branches.
3. Now step back and look at each individual main branch from several feet away.  Look straight on at the branches, then look at the same branch from the side.
   1. Straight on, the branch should be cascading gently downward.  There should not be any vertical protrusions breaking the wave.
      1. If there are, it means you missed vertical growth, and you should prune this vertical growth out.
   2. Same applies from the side-view.  There should be no breaks in the smooth cascade.
   3. A good simile for the branch, is your hand resting on a broom.  All fingers are loosely pointing out horizontally, and cascade downwards near the finger tips.  There are no fingers pointing up or at an angle.  Your Japanese Maple Tree branches should be the same.

End Result

When trained in this way, you will end up with a unique Japanese Maple Tree, which does not look like a big round Maple Tree when mature.  It will be a tree with character: Selective branches, that wind gracefully downward.  There will be portions of trunk exposed due to missing branches, further enhancing it’s beauty.

Compare this to an unpruned Japanese Maple Tree (Acer Palamtum) or a minimally pruned Japanese Maple Tree   At full maturity, it is large, circular, with criss crossed branches.  It’s big and unwieldy, great for bird nests, but not a true specimen tree in your Garden.

Dragon-Eye Japanese Red Pine

Dragon-Eye Japanese Red Pine - It's not a stand alone specimen tree ala "Bloodgood" or something similar, but like a good offensive lineman, this tree would make an awesome background to something nicer.

Dragon-Eye Japanese Red Pine (Pinus Densiflora "Oculus Draconis")

It’s not a stand alone specimen tree ala “Bloodgood” or something similar, but like a good offensive lineman, this tree would make an awesome background to something nicer.  I love the tree’s branching habit, and clumping branches.  Very exotic, yet hardy to Zone 4.

I have an area at the front of my lawn that is boring and lifeless.  I am thinking of planting this Red Pine with some boxwoods and Japanese Iris for a really nice contrasting front area.

Here are some specifications (From finegardening.com):

Botanical Name: Pinus densiflora ‘Oculus Draconis’ (PY-nus den-sih-FLOOR-ah)

Common Name: Dragon’s-eye Japanese red pine
Genus:  Pinus

Height:                      Over 30 ft.
Spread:                      15 ft. to 30 ft.
Growth Pace:        Slow Grower
Light:                         Full Sun to Part Shade
Moisture:                Adaptable
Characteristics: Interesting Bark; Showy Foliage
Foliage Color:      Evergreen
Uses:                           Hedge, Specimen Plant/ Focal Point
Seasonal Interest: Winter Interest, Spring Interest, Summer Interest, Fall Interest

This pine’s needles are marked with bands of yellow and green. The buttery yellow variegation on the 3- to 5-inch needles is present year-round, but intensifies as summer turns to fall and persists into winter. The scaly, fissured bark is lovely, ranging in color from gray to rich rusty orange. This is a graceful tree when mature, with an irregular branching habit and tilted trunk.

Noteworthy characteristics: Combines well with deep-green conifers or any other dark background. Use as a specimen tree, or for shelter or windbreaks. May look floppy and ungainly in its youth. Grows only about 6 inches a year.

Reference:

1. http://digitalflowerpictures.blogspot.com/2006/10/dragons-eye-japanese-red-pine-pinus.html

Books

1. 

   Garden Plants of Japan

   Garden Plants of Japan: Good reference material on Japanese plants.  Specifically, in our case, it speaks about the Red Pine.

On the positive side, the River Birch seems to be able to withstand a large amount of abuse, pollution and water. Plus, it has that amazing “Bark Peeling so I look like I’m dieing” look, that I love on trees. Nothing like a peeling tree in a boring fall garden! Overall a very nice specimen.  Some information about it:

Tree River Birch

Specific Name: Betula Nigra
Other Names:

• Birch river tree
• Tree River Birch
• River Leaf
• River Birch

River birch’s “Heritage” cultivar was selected 2002″ Tree of the Year” by the Society of Municipal Arborists. The River birch is extremely popular as an ornamental. It is hardy for all U.S. climate zones, is fast-growing, nicely forked, and wind and ice resistant. River birch peels in colorful flakes of brown, salmon, peach, orange, and lavender and is a bonus for regions deprived of paper and white birches.

The river birch is a large deciduous tree, growing 90 feet in height and spreading 30 to 50 feet. It grows at a medium to rapid rate, 30 to 40 feet over a 20-year period. River birches situated in moist areas live longer.  The river birch is among landscape trees recommended by many experts.

Birch grows in climates ranging from boreal to humid and tolerates wide variations in precipitation. Its northern limit of growth is arctic Canada and Alaska, in boreal spruce woodlands, in mountain and sub alpine forests of the western United States, the Great Plains, and in coniferous – deciduous forests of the Northeast and Great Lakes states.

Unlike other kinds of birch tree, the fruits of the River Birch mature in the spring following flowering. The trunk of this tree often is short, branching into several large limbs that grow upward. The bark of younger trees is pinkish to reddish brown. When older it is shaggy and silver-gray to black. The River Birch favors moist soils and typically is found growing on stream banks and in swampy lowlands. In her book on The Woody Plants of Ohio, Lucy Braun calls this a “semi-aquatic species” since it can survive flooding for several weeks at a time. This tree grows throughout most of the eastern United States and westward to eastern Oklahoma and eastern Texas. It is more common in the South, where it is the only birch tree that is found at low titleitudes.  although not of great commercial importance, manufacturers sometimes use it for furniture and woodenware. It also is planted for its ornamental value and is very effective in preventing stream bank erosion.

Books

There are actually no books in print, specifically on the River Birch Tree.  But there are several books about Birches that speak of the River Birch.  Here’s a list:

1. The American Woodland Garden: Capturing the Spirit of the Deciduous Forest

The American Woodland Garden: Capturing the Spirit of the Deciduous Forest

The recent popularity of river birch in North American gardens is due in large part to the introduction of especially light-barked cultivars including Betula Nigra "Heritage". The spacing of these trees in our garden at home directly emulates the close spacing often encountered in native populations.

River Birch Bark

Nearly Invulnerable to borer attack and is unquestionably the best birch for regions with high summer temperatures. Beautiful as a single-stemmed or multistemmed tree, river birch has the capacity to live well over a century and to exceed 100 feet in height. It is sometimes called red birch

2. The Birch: Bright Tree of Life – A book about birch

The Birch: Bright Tree of Life and Legend

3. North American Trees

Encyclopedia of North American Trees

Habit and Range

River birch is well named as it loves (wet) zones, adapts well to wet sites and reaches its maximum size in rich soils. However, the tree is very heat-tolerant and can survive modest droughts. River birch transplants easily at any age.  The tree is very intolerant to shade.

The graceful elegance of the birch allows it to be used as a specimen or for naturalizing, and is best used in large areas. It transplants easily and is most effective when planted in groupings. A multi-trunk specimen is more handsome than single-trunk trees. It should not be planted in high-use areas such as driveways, walks and patios, as dead branches tend to be messy. Periodic pruning is required to remove these branches; this can be done at any time of year. although the river birch thrives in wet areas, it does not require excessive amounts of water. It tolerates fairly dry soils once it is established. It requires acidic soils, suffering from iron deficiency if pH levels are 6.5 or higher. This species requires full sun and tolerates high temperatures. –as featured on Wikipedia

Animal Love

• Moose: Nutritional quality of the River Birch is poor in winter, but is important to wintering moose because of its sheer abundance in young stands.

  White-tailed Deer: though considered a “secondary-choice food”, it is an important dietary component. In Minnesota, white-tailed deer eat considerable amounts of birch leaves in the fall.

  Snowshoe hare browse birch seedlings and saplings.

  Porcupines feed on the inner bark

  Beaver also eat it though generally prefer aspen, while willow and paper birch are second choice foods.

  Voles and shrews eat the seeds.

  Numerous birds and small mammals eat paper birch buds, catkins and seeds.

  Young paper birch stands provide prime deer and moose cover.

River Birch

Birds

• Numerous cavity-nesting birds nest in birch, including woodpeckers, chickadees, nuthatches, and swallows.
• A favorite feeding tree of yellow-bellied sapsuckers, which peck holes in the bark to feed on the sap. Hummingbirds and red squirrels also feed at sap wells in paper birch created by sapsuckers.
• Ruffed grouse eat the catkins and buds.
• Redpolls, siskins, and chickadees obtain a considerable portion of their annual diet from birch seeds

Age

Growth Rate: The river birch is a large deciduous tree, growing 90 feet in height and spreading 30 to 50 feet. It grows at a medium to rapid rate, 30 to 40 feet over a 20-year period. It lives only 30 to 40 years on many urban sites, possibly due to a shortage of water. River birches situated in moist areas live longer.
The river birch is native to the American midwest, and is among landscape trees recommended by many experts.

Expert Comments

“Most birches are known for their beautiful bark, which can dominate any landscape in the dormant season.” – Guy Sternberg, Native Trees for North American Landscapes

“Only the shaggy brown river birch seems truly adapted to cities, holding its own with urban heat blasts and the deadly borer.”- Arthur Plotnik

“‘Heritage’[river birch] is an excellent selection with superior vigor, larger leaves, and greater resistance to leaf spot.” - Michael Dirr

Tree River Birch

References

• http://forestry.about.com/od/treeplanting/p/good_rbirch.htm
• http://www.cirrusimage.com/tree_river_birch.htm

Mail Order Birch Seeds

If you’re looking for River Birch Seeds, you can find them here:

1. Amazon

Conclusion

If you have the room for a tree river birch (aka River Leaf), then by all means plant it.  It takes little work to grow, looks great and will add a tree to your yard.  best yet, its maximum ht is reasonable.