View Full Version : Pruning native trees and shrubs

06-30-2003, 06:32 PM
What native woody plants lend themselves to pruning for
1. Improved aesthetics, e.g., illusion of age, planed out branches, dappled light through canopy, caorse-to-fine taper, directional movement.
2. Limiting size to 15` or less.

Isn`t it time we developed the cultural techniques for briniging signiature trees from California natural landscapes into smaller garden settings in a compressed, miniturized way like a landscape painting? Pruning tops, roots is just one possible method. How about grafting onto dwarf rootstocks, or cambium inversion?

Does anyone know of public or private gardens where woody speciaes are important to the design and where pruning or such plays an important role in enhancing the character of the design?

Here is a list of possible candidate species that interest me:
Acer circinatum, Arctostaphylos spp., Ceanothus spp., Cercis occidentalis, Cercocarpus betuloides, C. ledefolius, Corylus cornuta californica, Cupressus macrocarpa, Pinus Contorta, Populus tremuloides, Quercus spp.

I have some professional experience with some of these, but not enough! Referals to gardens, or knowlegeable people appreciated. Feel free to forward this email to them.

07-05-2003, 05:03 PM
Peter -

A number of native trees and shrubs do lend themselves to pruning and shaping, but I think many people don`t do much of it, as they want the plants to look natural. Certainly, Californians seem to prefer the wide, unfettered Fremontodendron to an espaliered version of the same shrub if they have the room.

Ceanothus generally don`t lend themselves to pruning, but there ar a few that do. I`ll have to see if I have any notes on those species. The general rule of thumb is to lightly prune Ceanothus when they are young - cutting smaller, developing branches works much better than cutting into large, established branches. Arctostaphylos are sometimes pruned, but this must be done with great care. The smaller shrubby species can get leaf and twig diseases both fungal and bacterial via pruning cuts, so the landscaping practice of turning Arcto. `Howard McMinn` into little cubes often results in a sick or dead plant. The larger Arctos are pruned sometimes like along paths so people don`t bump their heads on the branches. You can see good examples at the East Bay Regional Parks Botanic Garden in Berkeley. If you don`t live near there, maybe someone else can suggest another public garden. There is one theory that sensitive native shrubs like manzanitas should be pruned in summer when moisture levels are low, to avoid diseases that are spread in water. Of course, that wouldn`t work on the foggy north coast.

As for the rest of your list: Acer circinatum, Arctostaphylos spp., Ceanothus spp., Cercis occidentalis, Cercocarpus betuloides, C. ledefolius, Corylus cornuta californica, Cupressus macrocarpa,
Pinus Contorta, Populus tremuloides, Quercus spp.

Acer circinatum could probably be pruned when winter dormant - check some of the books on gardening with Pacific Northwest natives Kruckeberg wrote one, and you may find info.

Cercis occidentalis - it is such a very broad, dense, blobby thing by nature, that I`m not sure any amount of pruning would reform it.

Cercocarpus species: C. betuloides is a pretty well shaped small tree naturally, but its upright habit may not lend itself to artistic, or 'Japanese style' shaping. Worth a try, though. C. ledifolius grows much more slowly, and is probably sensitive to pruning in the manner of manzanitas, especially when grown away from its home range. In its natural state, it makes a very gnarly, picturesque shrub, but it`s not clear to what extent you could duplicate this in the mild conditions of a garden.

Corylus cornuta may have the best potential for pruning of any of them. On the Sonoma/Mendocino coast, one can see low, spreading shrubs that lean in one direction - a combination of wind and deer pruning. At Montara Mountain in San Mateo County, there are wonderfully shaped hazelnut bushes - presumably the result of steady deer pruning. In fact, I think they are along the Hazelnut trail. Someone should really do some controlled trials on different pruning regimes for this shrub.

Cupressus macrocarpa certainly can be and has been extensively pruned. The most notable example may be the celebrated umbrella trees of Manchester, in Mendocino County. They are right on Hwy. 1. There used to be some gumdrop trees in Ferndale that I believe were Monterey cypress, too. There was also a hedge-with-arched-doorway-middle on the San Mateo coast - maybe in Pescadero. Not sure what more 'natural' shapes this cypress would lend itself to, but whatever you do will take much time, work and vigilence for a tree that wants to be very wide.

Pinus contorta - certainly the coastal form, P. contorta var. contorta, should lend itself to esthetic pruning and shaping. I don`t know if anyone has tried it, though.

Populus tremuloides - Not clear how successful a pruning regime would be, given its tendency to sucker madly. You would get one aspen pruned nicely, and a bunch more unruly aspens would pop up. It is a pretty nicely shaped tree anyway, so not clear what you would gain by pruning.

Quercus - I have long wished to see more of California`s dwarf or 'scrub' oaks used in landscaping. I would think the Ceanothus rule would apply here - prune to shape when young.

Hope this helps,

Lori Hubbart
CNPS DKY Chapter</p>

08-28-2003, 03:14 PM
Corylus cornuta is the first thing I thought of with your description. Also when I think of traditional native pruning of natives, I think of coppicing cutting back to the ground to produce suckers and many natives are amenable to this treatment. </p>

08-28-2003, 03:15 PM
The other place you see pruning of natives is thinning for fire safety.</p>