Tree Protection in Seattle

Human design can hardly create a structure as long-lasting and alive as nature: trees.

Yet Seattle, like any city, ever-develops. (Track current construction projects in Seattle here.) Buildings come down in a day and new ones take forever to go up. The need to improve and create beauty stimulates renovation of all types. Ironically, landscape construction projects that will probably only last in the short term (before the next project comes along) can harm the long-term residents of it's site: the trees.

According to the International Society of Arboriculture, construction is one of the greatest causes of tree decline and death in urban environments (Arborist's Certification Study Guide, 2010). Trees may become stressed by physical damage to the trunk, branches and root systems, especially when re-grading must be done. Compaction (reduced pore space in soil that creates less aeration) occurs by heavy equipment constantly coming and going, as well as increased foot traffic. This causes reduced oxygen and increased carbon dioxide in the soil, as well as reduced water infiltration. Unfortunately the impact of these stresses may not show up for years, in the form of diseases and shortened life span.

Fortunately through trial and error, the City of Seattle has developed a set of regulations for protecting trees during construction projects, as found in the Tree Protection Ordinance (SMC 25.11) and Environmentally Critical Area Code (SMC 25.09). Read them here. There are three categories of trees covered by these regulations: 1) larger than 6" in diameter and taller than 4.5', 2) exceptional trees (those with high value for various reasons), and 3) hazardous trees. One category of trees that does not seem to be covered are very young trees.

The city claims to follow best practices developed by Oregon State University Extension. These guidelines are designed to preserve and protect tree health by minimizing disturbance to tree roots, the trunk or crown. For example, in order to protect the Critical Root Zone (CRZ, measured at 1 foot of radius outward from the base of the tree, per inch of diameter at 4.5' up the trunk from the base of the tree) strong fencing should be installed, with appropriate signage - as seen in the photo below:

[From SDOT Blog, City of Seattle, accessed 11/2/16]

But let us ask: when we look at the photo, while doing rough math - do you think enough radius of the CRZ is being protected? It's hard to tell, but perhaps enough protection is in place? Perhaps the cement mitigates some compaction? Also, only "exceptional trees" receive added protection with stem, branch and root padding. For both exceptional, and nonexceptional trees, no trenching should occur in the CRZ. What is enough protection, for which trees, and who decides?  Since if we look below at this generic picture of a tree, with root systems that extend laterally quite beyond the dripline/canopy of the tree, we have to question if the designated CRZ covers enough ground:

[From Dubose Tree Service, accessed 11/2/16]

It seems doubtful whether the regulations for protecting the CRZ are enough to protect roots from being severed, or to avoid damage to finer absorbing roots (which uptake nutrients and water). So really we are talking about mitigation. Enough planning in advance may minimize damage, and preparations for follow up tree care may help the tree heal from stresses incurred - call this "protection" if you want. Follow up maintenance strategies outlined by city protocol include mulch, fertilization (after one year), irrigation and pruning. Also trees should be inspected for 3-5 years after construction ends. Again we ought to ask - is five years enough time to determine the affect of a particular construction project on a tree's health? Clearly it's all a gamble.

One final photo to contemplate:

[From treesolutions.net, accessed 11/2/16]

First visualize what you believe the CRZ to be. Ask if the fencing is enough to protect the crown of this particular tree? Notice the cement terracing. This is another mitigation strategy to minimize the severing of roots when re-grading must occur. Additionally, if roots must be severed, the City advocates for "clean cuts". Do you believe damage and stress has been avoided in this picture? What do you think the tree will look five years from now? Will there be any die back? How long is this tree going to live?

Again take a look at the development map mentioned at the beginning: Seattle in Progress. How many trees do you imagine are being impacted in our city right now by construction, and how many are being properly cared for, throughout and after the process? How many trees will have the long full lives they might have had without the construction project carried out?



Works Cited

Lily, Sharon J. Arborist's Certification Study Guide. 3rd Ed. (International Society of Arboriculture, 2010).

Tree Protection Code. Seattle Department of Construction & Inspections. Web. November 2, 2016. http://www.seattle.gov/dpd/codesrules/codes/treeprotection/

"Tree Protection of Construction and Development Sites: A Best Management Practices Guidebook for the Pacific Northwest". Oregon State University Extension. December 2009. Web. November 2, 2016. http://www.seattle.gov/dpd/cs/groups/pan/@pan/documents/web_informational/p2209364.pdf.

Pruning Prunus

The act of pruning plants can make drastic changes to an environment; the line between cultivating harmony and causing harm is thin. The power of pruning tools must be wielded conscientiously. And so the ethical code of yoga philosophy may be appropriately applied here. Let us consider the yamas, relational restraints, and niyamas, self-discipline, which are the first two limbs of yoga - as we consider approaching the work of pruning the fruit tree, Prunus (species unknown).

Do No Harm

The Yoga Sutras teach us that the greatest virtue, which all other yogic principles bow to is ahimsa, or non-harming. This ancient principle often associated with Gandhi or Dr. Martin Luther King Jr., and nonviolent social change,  is a wise choice for interacting with plants. Gardeners uneducated on proper pruning techniques, without an intuitive sense to listen to plants - may overprune, or improperly prune, perhaps inviting decay, disease or even death. I have been that gardener. Ignorance, lack of experience and failing to listen can carry irreversible mistakes, and plants are no less deserving of respect than humans. We need to remember that harmful pruning practices reverberate back to ourselves, manifesting in unhealthy landscapes, or unfulfilled harmony and beauty. If we make non-harming a central principle that guides our pruning practice, we will advance conservatively, and will be far less likely to inflict long-term damage.

For example we have a Prunus where we rent, which is in very bad shape due to previous pruning jobs. It's basic structure has been hacked down and is lopsided. I am not sure why this was necessary, because the tree is in the middle of the yard with no wires surrounding it, getting in no one's way; I wonder what the pruner was seeking. Gaping crevices remain where the tree tried to compartmentalize injury in it's race to shut out decay. This beautiful tree is like a veteran soldier who lost limbs during war. Yet proper pruning techniques and respect for the tree could have maintained a beautiful structure while limiting the onset of wound rot, that resulting in more longevity.

In the first image you can see the remaining stub after an indiscriminate "heading" cut was made of a lower limb. In the second image you can see some of the effects of rot, created by improper pruning cuts. The critical thing to remember is plants do not "heal" after injury - they wall off decay (a process typically referred to as the Compartmentalization of Decay in Trees, or CODIT). Also, pruning is not like cutting hair, which may be more akin to "removing deadwood". And so when you make a pruning cut you risk creating injury and opening up the plant to decay. Trees notably have four walls of defense to protect themselves from rot, which involves specialized cell production of increasing strength. It may take a couple of years for a tree to produce Wall 4 wood cells containing fungicides, which is plenty of time for decomposition to set in [1].

Properly Pruning Prunus

Pruning fruit trees can be complicated, but no so much that harm is justified. This is especially true in the case of ornamental fruit trees, where we are not making cuts to increase fruit production. Each tree has it's own personal "pruning budget" of what can be reasonably tolerated - the same way that humans can only tolerate so much stress before their health suffers.

If pruning causes injury, or harm, one might ask if pruning is necessary at all. We must remember that for the sake of maintaining health it may be necessary to prune selectively - if not pruning at all will be harmful. This particular Prunus seems to have been trained early on with an "open-center" with four scaffold limbs - perhaps by weighting or bending. As a result it offers ample blooms, so what need is there to prune for anything but health? The only pruning that should have been considered would be to avoid limb breakage (such as by removing crossing branches) or "selective thinning" cuts within the canopy to increase light and air circulation [2]. The pruning budget for any tree will be smaller than you think, especially in light of the principle of nonharming.

Perhaps we might give this past pruner in question the benefit of the doubt - perhaps part of the scaffold needed to be removed due to limb breakage. Yet they still needed to be careful to cut just outside the "branch collar". The branch collar is specialized tissue at the base of each branch where CODIT cells are performed. It is an important connector between the tree's heartwood and branches, which are made of different kinds of wood. Each year as the trunk produces new wood it's rings enclose the branch collar as well as the rest of the trunk, which is why branch collars look like bulges at the base of branches. This type of wood does not surround branches, so losing a limb is not the end of the world. Yet losing a limb reduces a tree's capacity for photosynthesis, and to receive food and energy. If you cut into the branch collar you interfere with the tree's cycling of nutrients and water, and open the tree up to decay. If you cut too far away from the branch collar you do not activate CODIT as quickly so rot may overtake more tissue then necessary. Therefore you need to make a cut in the right location.

Nonharmful Guidlines for Pruning:

* The right amount: limit yourself to only removing dead, diseased and damaged wood. Other pruning cuts should be endeavor to prevent limb breakage, or thinning of the canopy. Focus energy on serving the health of the tree. 

* At the right time: while this varies between species, generally seek agreeable climate, but not during peak growing season - to reduce the risk of bacterial infection. This will probably be early Spring. Do the research.

* In the right location: make pruning cuts just outside the branch collar to collaborate with the tree's CODIT process. Again, research best practices for your plant in question before making cuts.

* In the right spirit: ask yourself what your true intentions are for making any pruning cuts whatsoever, take your time, and listen deeply. Remember that less pruning is less work, which may be better for all. 

Contentment, Non-Grasping and the Middle Ground 

Other principles from the yamas and niyamas may be brought in for consideration. Santosha (contentment), reminds us that every plant has it's own unique beauty and purpose, which is probably not for pleasing our own personal aesthetics or hunger requirements. If we can accept the beauty of each particular plant we will be more likely to be content with it as it is, rather than making drastic, possibly harmful impact. Aparigraha (non-grasping) is related to santosha wherein we don't need to push our own agenda on the plant and make it give us what we want. Also if we can share the plant's abundance with other species, we let the plant exist in relationship to all. Brahmacharya invites us to take all actions in moderation, or in other words to respect pruning budgets. As well as only making the right amount of cuts, at the right time, in the right location, in the right spirit. This offers the best chance for maintaining vitality in the long haul. Considering all these principles allows us to get into the right mindset or spirit in order to make wise choices for pruning.

Protecting the Health of the Pruner

No doubt pruning can be a lot of hard work. In our effort to protect the longevity of plants through wise pruning practices, we need to protect our own longevity. The best practice as you work is to move slowly and mindfully - pay attention to how your body and intuition is responding in your interaction with the plant. This offers the best chance for you to maintain awareness of how you are holding your body and mind as you make cuts - in order to do no harm to yourself. This goes beyond using good, clean, sharp tools, protective eye wear and gloves. Imagine that you want to be able to work with plants until old age, with as much ease as possible. You need to avoid repetitive stress or poor posture habits to keep your muscles and joints flexible and strong for as long as possible. Think of pruning as exercise and be in your body fully during the whole process, letting it be more of a meditation.

Here is where the other limbs of yoga come into play: asana, the poses, and the other four which function as gateways into samadhi or a state of enlightened bliss. Doesn't that sound nice? Consider these final yogic tips:

* Warm Up: do some gentle shoulder and neck opening to get blood and energy flowing in the primary muscles you will be using. Think of fluid movement intended to open all joints from the hands all the way into the neck and core body. Circle and rotate every joint you can for at least five minutes. Notice the energetic changes you create from simple movements.

* Move with mindfulness: be present in your body no matter what you are doing, whether it's setting up an orchard ladder, reaching for a tool, or squeezing hand pruners. Notice the waves of impact from head to location of activity, and back again, as your nervous system responds to your immediate environment. Notice where tension builds up, or where energy flows are halted. 

* Rehabilitate: in our movement patterns we tend to go the path of least resistance, which is where bad postural habits develop. In your mindful movement you will notice tension and pain, and you can return to those places in the body later, with specific exercises designed to restore those areas to good form. Shoulder opening, heart opening, wrist strengthening and many standing yoga poses are great for this [3]. Give yourself an hour to explore various yoga poses.

* Rest: The best method toward longevity is to relax. Stop using your body, put it in a posturally sound position like sitting upright or laying flat on the floor, and just chill out. The more you relax the more emotional stability and mental clarity is made possible.

Works Cited

[1] "How Trees React to Wounding - CODIT". Article, still determining source.
[2] Turnbull, Cass. Guide to Pruning (Sasquatch Books, 2012)
[3] "Yoga Poses". Yoga Journal. Web. February 25, 2016. <http://www.yogajournal.com/category/poses/>.

Soil Test

The home that I rent in Upper Fremont has a rundown house, haphazard garden, and up until last year blackberry thicket covered the yard. 

Last year two friends cleared the blackberry out and tilled the ground, then created tidy little rows to plant a garden. One day in May they had a planting party and asked me to improvise a plan for seeding. I thought about sun requirements and families, and threw a diagram together. A big group of us planted seeds in the little rows, including herbs, greens, peas, beet, carrot, chard, tomato, pepper and pumpkin. It was essentially a grand experiment with little observation of the land, and no plan! However, it wasn't long before many seeds sprouted - though no peppers, and some more fully than others. With a makeshift irrigation system, and a little tending, we were able to watch the outcome of our best efforts. I ended up spending more time with this garden through the summer and into the fall, when I finally moved in Dec 1. 

My (now) boyfriend and I maintain the garden and are slowly learning how the soil influenced last year's yield, so we can improve soil in the upcoming year. We wish to create the conditions for our desired plants to thrive, perhaps discouraging so many weeds, pests and diseases. We are well aware that 'we are what we eat', or, like our food, we are "truly a product of the soil and reflect in [our] bodies - and minds - the wealth or poverty of the land" (Kohnke & Franzmeier 4). We also know our soil is not that dark.

Last year in late summer I sent soil samples to King Conservation District. All King County residents are eligible for one free soil test a year totaling five samples. King Conservation District contracts with A & L Western Agricultural Laboratories in Portland, OR to conduct the analysis. I sent my samples in the mail and received results through email!

Here are snapshots of test results for my two samples:

In addition to lab results we received a Soil Analysis Booklet PDF created by Peaceful Valley Farm Supply - an organization that began in 1976 out of Nevada City, CA, and currently operates the website groworganic.com. Their booklet is specifically directed at chemical analysis (rather than biological or physical).

Instead of providing a thorough analysis of our lab results, I thought I would highlight what appears to be going well, and what needs improvement. Of course this is based on one soil test taken late summer, and likely the results would be different depending on the time of year, and would be different now, reflecting our efforts over the fall/winter:

Organic Matter/humus

We need high organic matter because it binds to clay/minerals to create water-stable aggregates. This type of soil structure facilitates the slow release of nutrition and proper drainage - thereby nourishing "good tilth" (Kohnke & Franzmeier 13). Since organic matter reads above 5% in our soil test, we don't need to worry about adding more (PVFS 3). Formally the soil was covered by invasive grasses and weeds with ongoing root structure being broken down, which possibly explains the organic matter. Also our cool, moist Maritime climate favors humus formation (Kohnke & Franzmeier 54). However organic matter is always being broken down, so in order to maintain current levels, we will need to continue producing biomass through cover crop, or collecting other plant material on site for mulch, as well as using arborist wood chips.

N-P-K

Nitrogen facilitates quick growth response; phosphorus is key for flowering, fruiting, and rooting; and potassium is important for regulating metabolism (PVFS 4-7). Nitrogen, potassium and phosphorus are the elements most needed for crop yield, so we are lucky our reading is Med-High. We won't have to stress about fertilizing - although our test results indicate imbalance. Since we have slightly lower potassium we may want to add a little, which may inadvertently raise pH (PVFS 7). Yet we don't know how much nutrient loss occurred over the fall/winter, and the amount of plant nutrients taken up by crops and removed from the field vary a great deal from year to year (Kohnke & Franzmeier 43). It will be interesting to see what next year's soil test results show. We overwintered nitrogen-fixing cover crop and will grow peas so hopefully we can fertilize via biomass.

Magnesium and Calcium

Calcium, magnesium and sulfur are secondary plant food elements (Kohnke & Franzmeier 37) and unfortunately our readings are Low to Med-Low. Magnesium is important for chlorophyll production and the uptake of phosphorus; calcium is critical for cell wall structure; and sulfur for the fabrication of proteins (PVFS 8-11). Since our pH is low, perhaps influenced by the strong presence of acidic blackberry, it makes sense that our magnesium and calcium levels are low (the higher they are the typically more alkaline the soil). Because the levels are so low we may need to fertilize beyond adding compost to the soil, while trying to raise pH. One concern with adding lime or gypsum, however, is they can contribute to cementation at lower horizon levels, as mineral weathering accumulates to form a pan (Kohnke & Franzmeier 73) thus diminishing drainage over time. Perhaps just a tiny bit of fertilizing will go a long way.

pH

Our low pH could originate from our moderate rainfall climate (PVFS 14), which encourages an environment where blackberry can thrive in disturbed soil, and perpetuate an acidic soil. However this information alone does not mean we necessarily need to add lime (ibid). It really depends on which crops we want to grow and their pH preferences. So we may want to cultivate microclimates based on pH requirements, because we want to grow some acid-loving foods like potatoes, but also some alkaline-loving foods like Brassicas. However since most crops thrive in pH 6.5-6.8 we generally want to work in that direction (Kohnke & Franzmeier 30) . We could experiment with not adding lime and seeing how next year's soil samples read, simply from adding compost and mulch.

Cation Exchange Capacity

CEC represents the soil's ability to retain and release cations for later use, and the higher the number, they greater the capacity. Our reading, which ranges from 10.5-11.7 is considered low, however if we continue to add compost and cover crop, we may steadily build humus to reach a level of 20 (PVFS 14). This little bit of information is particularly important in relation to pH. We have low pH, possibly due to low calcium -- but if we add lime to increase calcium, our low CEC may not be able to retain it (ibid) rendering the effort useless (and possibly just leaching to create a hard pan in the subsoil!) To connect back to our organic matter levels - which are high - because we have low CEC we need to "promote biological activity" to help break organic matter down, in order to release plant nutrient. The more microbes there are, the more fertile the soil (Kohnke & Franzmeier 57). This may be are best angle toward raising CEC: add compost or even microbial inoculations (PVFS 3). Arborist wood chips may be the most affordable option (free) for building microbial activity.

Summary

Our soil test results suggested that we fertilize with lime, nitrogen, potassium and sulfur. Yet as Toby Hemenway aptly put, "In nature, fertility comes from the vegetation and soil life, not from a bag of fertilizer" (Hemenway 31). Indeed we wish to mimic nature in our efforts to build soil. Our goal is to facilitate "good tilth" so we will take the following steps: build biomass, mulch with arborist wood chips, add compost to the soil, plant nitrogen fixers, and cultivate pH microclimates. Ideally these steps will equate to the permaculture approach of "making the least change for the greatest effect" (Hemenway 6).

Works Cited

Kohnke, Helmut and D.P. Franzmeier. Soil Science Simplified. 4th Edition. Long Grove, IL: Waveland Press, 1995. Print.

Peaceful Valley Farm Supply. Understanding Your Soil Analysis Report. 2004, PDF file.

Hemenway, Toby. Gaia's Garden. 2nd Edition. White River Junction, VT: Chelsea Green Publishing, 2009. Print.

New Year!

It is unbelievable to me that I posted nothing since May 2015.

In the meantime I started becoming more involved with a garden plot in upper Fremont, where I finally moved in December 2015. Here are some photos which accumulated over those seven months:

The Most Successful Plant Award goes to the row of swiss chard planted May 2, 2015. I wonder what it is about the soil that allows this plant to do so well with just a little maintenance to regulate the occasional Cercospora leaf spot. 

It will be my fourth season of trying to grow garlic. I had a minor failure last year where I learned leaving mulch on too long may cause oversaturation of the bulbs, and lead to rot. In this case the bed was not raised, yet there was a decent amount of organic matter. In the raised bed (pictured) the garlic followed a crop of fava beans and was generously given compost so I hope it will be a more successful crop. 

I had my first experience growing Jerusalem artichoke! Great abundance despite the persistence of powdery mildew. I learned that they prefer full sun, so next year I will find a different place in the garden.

We grew a pumpkin! It was the only one that made it, somehow, in partial shade. I loved watching it's vines spread through the corn and tomatoes seeking more sun. This plant suffered from terrible powdery mildew and it's crown jewel was truly the result of struggle. It was wonderful to make all kinds of foods and desserts with this beauty all the holidays for friends and family. This pumpkin almost became a pet as it cured in our living room, I wish we could have kept it around longer. 

This is our old pear tree with the ivy that wants to take over. Our giant brush pile rat castle is next to it, and the chicken coop, where we are still installing a run to bring chickens in this Spring. 

It's going to be an interesting year!