Category Archives: Trees

The Strength to Stand: Surviving the Load of Ice and Snow in Portland

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The morning after the big snow along the front of my house. To the left, splayed out and weighted down, is my Butia capitata. This one, from Argentina and not used to snow, had me worried, but it sprung back. The Oleander to the right, next to the sign, was bent down to the ground from its 8’+. Further back is one of my Chinese Windmill Palms, Trachycarpus fortuneii, bent under a snow load it is used to from high in the mountains of southern China.

Many of us who garden in the Pacific Northwest, and especially those of us in Portland this year, will be visiting our garden centers and favorite nurseries this spring and summer with a little more anxiety and need as we look for plants to replace those that have succumbed to this winter’s cold, ice and snow loads, all of which were more severe than what we have come to expect here.  But before we pull on our boots and don our rain gear to head off for shopping there are several questions that we need to consider before we make our purchases.  Not all of us draw up plant lists, but most of us at least carry in our heads a wish list of plants we have seen in other gardens, in magazine spreads and while on vacations, but if we want to avoid some major mistakes and move our gardens toward the kind of landscapes that we really want, we are going to have to put on our reality goggles and critically assess our choices…that is, if we want to avoid unnecessary losses in the future. Continue reading

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Summer Tree Failure

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A failed Norway Maple on SE 49th. This picture was taken June 28th, five days after a big rain event. You can see that this tree has been struggling for some time as evidenced by the dead branches still in its crown and the stressed flagging leaves up there. The girth of the trunk is greater than the width of its planting space. It is pinched beneath the overhead lines and the requirements for street trees regarding road clearance. It’s height has been ‘controlled’ and limited over the years.

Trees fail all of the time and when they are older, this can be quite spectacular, or devastating, if your car, home or an individual have the misfortune of being in the its path.  Like most people I used to believe that most such failures happened as the result of storms, and many do, but it is relatively common for trees, or major limbs, to come crashing down with calm conditions in the Spring. The new flush of growth brings with it a great deal more tissue and water weight than a tree in active growth has previously supported or, for a tree struggling, compromised by the burden of significant rot in its core and/or limbs.  Look at any tree and look at its girth, its canopy spread and on many species, its long, often horizontal limbs and try to imagine their weight.  To help with this fill a couple of buckets with water, lift them and try to hold them horizontal away from your body.  Trees are static structures, comprised of countless overlapping fibrous layers, much of it hard and rigid with a great deal of compression and torsional strength.  The were ‘born’ for this.  Few of us would last for more than a few seconds trying to support so much of our own weight on extended arms.  We shouldn’t be surprised when they fail, even as elegant and as well ‘engineered’ as they are. Continue reading

The Fields Park: Brownfields, Compaction & Drainage – a Missed Opportunity

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The Park enterance, framed by the four bio-swales (I can’t bring myself to call them ‘water gardens’ as they look very ‘un-garden like’) that take runoff from the adjacent hard surface as well as from the drain system installed across the lawn. They are planted with Betula nigra cultivars along with Cornus stolonifera ‘Isanti’, C. s. ‘Kelseyii and an Iris. As you walk through the Park you will move over eight different hard surface treatments!

The Fields (Click here to see the final design plan), completed in spring of 2013, is Portland’s newest Park in the north end of the Pearl District.   While I was still with Parks I did the horticultural review during the design process and was an on site inspector, periodically, during construction.  New Parks like this one require a huge time commitment by Parks.  Selection of designers, outreach to all of the stakeholders and many other meetings involving more technical aspects of such a project all in an effort to deliver to residents a Park that is beautiful, serves the needs of residents and is affordable in terms of long term maintenance.  Before  the project is offered to the design community functional goals are set for the Park and a general design theme is chosen.  Various firms offer proposals.  Concepts are bandied about.  Eventually, one is chosen.  In this case, the Office of Cheryl Barton, a San Francisco firm, was awarded the design contract (To see what they have to say about it). Continue reading

Pruning: The Aesthetic Choice, Consistency & Good Horticultural Practice

The Pruning Series, 3

Illustrations from 'Pretty Deadly', written bj Kelly Sue Deconnick, art Emma Rios, colors Jordie Bellaire, Image Comics 2015

Illustration from ‘Pretty Deadly’, written by Kelly Sue Deconnick, art Emma Rios, colors Jordie Bellaire, Image Comics 2015, (007-002).  Straight-up classic art, whether oil painting or illustration, like these two pages from a graphic novel that I find beautiful, involve ‘craft and, an understanding of one’s materials and techniques, that are necessary for any artist to create work. In illustration, like this, the art must resonate with the story to be successful. Horticulture and pruning are no different.

Plants often present pruning challenges to the gardener.  I’ve already introduced the issue of understanding ‘why’ you are choosing to prune, the physical structure of a ‘normally’ growing individual and how it will respond to the cuts you choose to make.  There are several good books out there that discuss how and what constitutes a ‘good’ individual cut and what approach you might take with different types of growers…it should be the goal of any gardener to understand the technical details of pruning, so that they become ‘natural’, reflexive. (In an earlier posting, I discuss pruning tools and provide an introduction to what constitutes a ‘good’ pruning cut.) Like all artists we develop a style that may distinguish us from others.  Even understanding all of this and possessing the technical competencies there are the ‘aesthetic’ decisions the gardener/pruner must make.  Two different gardeners can prune in the same landscape and it can be obvious when they are finished that they have very different aesthetics.  The results can be ‘disjointed’ or harmonious.  Every plant, every branch, every internode, presents a choice and because each individual plant of a given species or variety, though it may grow following a shared genetic code, will grow uniquely in response to the physical conditions it faces…and the damage and pruning it has received over its life.  Like most things in life our control of a plant is limited and the more we attempt to control it the less like itself it will be. Continue reading

Pruning…Why do we do it? Cutting Woody Plants Down to Size

The Pruning Series, 2

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This Fagus sylvatica has been in this pot around 20 years. I grew it from seed 30 years ago from a mother tree in Sellwood that has a canopy 100′ across. It is approximately the same age as the trees pictured below.

I’ve heard it said often enough that trees and shrubs got by just fine for millions of years before we started pruning them, so why do it now?  That’s a good question and if you can’t answer it, you shouldn’t be pruning.  Horrible examples are all around us.  Trees repeatedly stubbed off their natural branching form and elegance destroyed.  Others sporting long scars where someone removed a branch with a single top cut causing the branch to drop pulling a long tongue down the trunk where it was still attached.  Still more with split trunks and scaffold limbs where multiple sprouts, vying for dominance fail and tear down.  Poor pruning has lead to the collapse and premature deaths of many trees and reduced many shrubs to inelegant space fillers jammed up agains buildings.  The first thing you should ask yourself is, ‘Why I’m I doing this?” Continue reading

Choosing Trees for Larger Public Landscapes (and your yard!)

Still one of my favorite Oak photos. This one take in the late afternoon beneath a canopy of Interior Live Oak (I think) at Shiloh Ranch Park, last March.

Still one of my favorite Oak photos. This one take in the late afternoon beneath a canopy of Interior Live Oak (I think) at Shiloh Ranch RegionalPark, near Windsor, CA, last March.

A friend recently asked me if I had some favorite trees that I would recommend for planting on school landscapes, that would be like asking if I had favorite park trees, no I don’t…and I don’t have a list of proven performers either. A planting site being located at a school, only tells me something about the uses/abuses one can likely expect on a site, and nothing more. When we choose plants we need to be paying attention to a lot more than that. Many people are intimidated when it comes to choosing trees, there are so many and potentially, they live so long, growing from year to year…all of this tends to magnify the ‘weight’ of our decision.  People often look for short cuts because there are so many things to keep in mind when choosing. There are two major questions that need consideration first, the site conditions and design, what will the tree have to put up with and what do you expect? Continue reading

Palms I Have Grown: A Look into Trachycarpus and its Intimates

 

Trachycarpus fortunei - My oldest tree.  The house's gutter is at 13'.  This is the most robust, stoutest, of the 5 T.f. that I have with the broadest canopy.  It's male.  I've just finished cleaning up its rattiest older fronds.

Trachycarpus fortunei – My oldest Palm tree. The house’s gutter is at 13′. This is the most robust, stoutest, of the 5 T.f. that I have with the broadest canopy. It’s male. I’ve just finished cleaning up its rattiest older fronds.  I remove 15-20 every year and have been annually while it’s been in its adult active growth phase.  It will slow down when it begins to approach its maximum height and maturity.

Continue reading