All posts by Natalie Martell

By Julia Prince

As an intern at BASE, I was brought on to help leverage support for the Dolores Street Pollinator Boulevard by communicating the project’s positive social and ecological impacts in the area. I came with some photography and writing skills under my belt but had never touched any Adobe programs. I was granted complete creative freedom and thrown into the fire, so to speak. After all, there is no better way to have a deep learning experience than to figure something out for yourself, from end-to-end . I grappled for a while over what to create that would move people to back this project. What I produced was a video, lots of photos, blog posts, and the visuals shown below. These visuals represent my research-based hypothesis that the sheet mulching and drought-tolerant, native plantings on the Pollinator Boulevard are having a positive, long-term impact on the ground which the new gardens inhabit, in terms of plant health, soil nutrient composition, structure, and fertility.

As we look toward developing the third median on Dolores Street, we are considering the metrics through which to quantifiably measure the social and environmental impacts the project is having on the surrounding area. Some of the methods we seek to employ are pollinator counts, post occupancy assessments, measurements of water retention, and soil tests.

At the end of March, we honed in on one of these measurements of impact and collected soil samples from Median 1, which was sheet mulched in August 2015 and planted in March 2016, from Median 2, which was sheet mulched in October 2016 and planted the day we collected the sample, and from Median 3, which we have yet to begin working on at all. We dug down about 6 inches and filled a small plastic baggy with soil from two points, at either end, of each median. We sent the samples into the Michigan State University lab for testing and received results well in line with the initial hypotheses conveyed in the diagrams below.

With concrete measurements of the changes being made for both people and the planet by installing the Pollinator Boulevard, we hope to galvanize engagement, educate the public, broaden our support network, and create an effective and replicable template for a community-driven, urban gardening, project.

This is the first of a series of images which depict my assumptions of how the soil is changed by the process of sheet mulching and the establishment of native, drought tolerant, plants. Separated down the middle by a Canary Island Date Palm, the iconic trees that line Dolores Street, it is a comprehensive, before and after view of the ground under the median. It shows on the left the sheet mulched and planted, Pollinator Boulevard median 1 and on the right, an untouched median like median 3. On the right, we see compacted, desiccated, nutrient leached soil, low in organic matter and microbial activity. In contrast, the left side is characterized by rejuvenation of the soil horizons and palm roots due to the accumulation of organic matter, increased microbial activity, greater availability and retention of nutrients, and improved soil structure.

My research revealed how all of these soil metrics–microbial activity, nutrient and mineral composition, organic matter content, and structure–are so interdependent on one another. It’s a bit of chicken before the egg when it comes to measuring soil quality. Essentially, soil metrics provide a tightly integrated, positively correlated, and closed feedback loop.

On the left side, I hypothesized that sheet mulching has assisted in the creation of humus, thus reinstating the nutrient rich, surface soil, or Horizon O. Deep rooted, perennial plantings also build humus down through Horizon A. Organic matter invites microbial activity which mineralizes nutrients, making them more available to plant roots. Thus, the roots of the plants are able to grow deeper and maintain their own health without the addition of fertilizers. Native root penetration and microbial activity breaks up compacted soil and leads to the formation of aggregates. As a result, the roots of the Canary Island Date Palms should be able to take on a more natural structure as they get a boost of available nutrients and water, and soil compaction is relieved. However, any drastic change to the palm roots could not be proven by a soil test alone and is thus still only a hypothesis.

What our soil test did prove true were the expected changes in soil organic matter. Organic matter is added to the soil by decaying organisms, like plants, microbes, and fungus. Our soil samples were dug from top Horizons O and A and showed an organic matter content of 32.4% in median 1, 13% in median 2, and median 3, in the absence of any Horizon O, contained only 9.3%. Furthermore, the soil type in median 1 was indicated to be “organic”, median 2 was “mineral, loam”, and median 3 was “mineral, sandy loam”. Sheet mulching and deep-rooted, perennial, plantings increased the organic matter content on median 1, while sheet mulching alone increased the organic matter content of median 2. This drastic increase in organic matter among the surface soil layers between median 3 to median 1 indicates positively correlated shifts in nutrient retention, microbial activity, soil structure, and plant health.

The visual may or may not be an over-dramatization of the differences in soil and root health between the medians and to prove that would require further investigation. However, the test results, which are restricted to only the surface soil layers, do support my hypotheses in regards to the A Horizons. With proven organic matter increases, we can qualitatively infer positively correlated growth in the other soil metrics. As originally hypothesized, median 1, represented by the left side of the visual, has a soil Horizon A that is, “[A] Combination of organic and inorganic matter…[where] A high concentration of roots and soil microorganisms lead to the development of humus and soil aggregates, plus facility of air/ water exchange within this horizon and on to lower ones. Abundant microbial activity mineralizes organic nutrients to support root growth and plant/tree health.” In turn, median 3, represented by the right side of the visual, has a Horizon A characterized by, “Extremely shallow roots [that] lead to low amounts of organic matter and microbial activity, causing minimal formation of soil aggregates. In the absence of macro-pores, air and water permeation are restricted, further exacerbating the decline of microbial activity. With low instances of organic nutrient mineralization, plants and trees suffer.”

The visual to the right represents, more specifically, the improved soil structure which should result from increased organic matter. The right side, once again, represents median 3 and the left side represents median 1. Soil compaction, brought on by years of shallow-rooted, turf grass plantings and human activity on the surface of the medians, should be reduced from median 3 to median 1 as a result of the Pollinator Boulevard’s sheet mulching, perennial plantings, and subsequent increases in organic matter and microbial activity. More organic matter, due to the building of humus that leaches down into Horizon A, invites microbial activity. The movement and waste of these micro-organisms contributes to the formation of soil aggregates. Thus macro-pores are created, allowing water molecules and nutrients to penetrate the soil. More moisture and organic matter molecules invite even greater concentrations of microbes, which metabolize the nutrients present in the organic matter, making them more available to plant roots. The movement of water through the soil also allows nutrients to travel to deeper horizons and root zones. Increased nutrient availability makes for healthy plants and a sustained source of material to be decayed into organic matter. Thus, the cycle continues.

This last visual on the right specifically shows how microbial activity is effected by increased levels of soil organic matter. The top image represents the stifled soil food web of median 3, while the lower image represents the prosperous soil food web of median 1. Median 3 has low organic matter content and that which exists is being metabolized by algae and mosses. Thus at the first trophic level, organic matter feeders are dominated by bacteria and some disease fungi. Mycorrhizal fungi are not present due to a low concentration of roots. Insect pests dominate the consumption of unprotected shoots and roots and there are few earthworms. Median 1 has high organic matter content metabolized by algae, P-bacteria, and lichen. The first trophic level is dominated by organic matter feeders like saprophytic fungi,  accompanied by bacteria and acetinomyces. High levels of mycorrhizal fungi support an abundance of roots and keep insect pests in check. There are more earthworms present, as well. Without beneficial fungi, median 3’s second trophic level consumers are dominated by bacterial feeders like nematodes, protozoa, and rotifera. There is an absence of fungal feeder and few white worms to feed on insect pests. Median 1’s second trophic level is dominated by fungal feeders like springtails, mold mites, beetle mites, and feather winged beetles. There are beneficial levels of bacterial feeders and white worms keep insect pests in check. At the third trophic level, median 3 has a low density of consumers while median 1 has a beneficial level.

I hope these diagrams give the viewer a closer look at the changes that take place in the soil when organic matter content differentiates,  enlightening the intricacies, delicate balance and interwoven nature of the Earth beneath our feet. Like a Jenga tower, you can only take so many pieces out before things start to lean over and the whole thing collapses. Alas, we rebuild.

One rainy afternoon in early March, we decided to take a little nursery field trip. After a short drive through the farmland west of Portland, we made our way on winding roads through the forest until we arrived at the beautiful bamboo oasis that is the Bamboo Garden Nursery. The 20 acre garden holds over 300 varieties of bamboo with varying color combinations and distinctive features. We were greeted by Noah Bell, the nursery manager, who offered to take us on a tour of the grounds in his golf cart. We happily accepted. It was so fun to see the different greenhouses, learn about some different propagation techniques, and see some of the experimental propagation. If you ever get a chance to go check this nursery out, don’t pass it up!

Written by Julia Prince

A pollinator at work in the first median.

A pollinator at work in the first median.

This past Saturday, October 1st, the Pollinator Boulevard opened its wings a little wider as we finished mulching the second median on Dolores Street. With the first median at the intersection of Market Street already completed and in full bloom, transforming the second median from dried out turf to a flourishing garden puts us one step closer to our goal; creating a continuous band of pollinator habitat down the medians of historic, Dolores Street.

The fruits of our labor; a bee transporting red pollen.

The fruits of our labor; a bee transporting red pollen.

Why, you ask? For those of you who are unfamiliar with the Dolores Street Pollinator Boulevard, allow me to explain. This is the passion project of BASE and Patricia’s nonprofit, With Honey in the Heart, an organization dedicated to raising awareness about the importance of pollinators and increasing their habitat. The vision of Patricia and the community which has materialized around and embraced the project is multifaceted: to beautify the street that is starved for color and life, to create habitat for the pollinators we need and love, to give nature a place in the city, to educate the public about ecology, to bring the community together over common goals, and to give the neighborhood a sense of identity to be proud of.

Sheet mulching day volunteers.

Sheet mulching day volunteers.

We were able to get our hands in the dirt once the Department of Public Works approved the plan for the second median, the local community contributed to the final design, Prado Group payed for the turf removal and Whole Foods Market and Bayview Green Waste offered to donate the necessary materials for the task. To pull together enough people for the job, we drew from the network of volunteers that has surfaced in support of the Pollinator Boulevard. It was great to see some friendly faces, welcome newcomers, and deepen the connections that have been born from this project. We are proud to establish common ground for local stakeholders invested in the health, beauty, and ecology of the neighborhood to meet, share ideas, and impact their community.

A beautiful day to sheet mulch!

A beautiful day to sheet mulch!

After tearing out the existing turf, sheet mulching is the second step in installing the newest garden. It is also a necessary step in establishing a fruitful, organic, landscape. Often times, when gardeners are transforming an unproductive, weedy, area into a new design, they will apply chemicals to eradicate weeds and additional chemicals to build nutrients in the soil. Sheet mulching is a permaculture technique that both builds rich soil and eliminates weeds without the need for chemicals that have harmful effects on the environment. Layers of nitrogen and carbon rich materials are spread over the ground, breaking down naturally over time, proliferating organic matter in the soil, and suppressing weeds.  Making sure weeds are at bay before installing a new garden is vital at a site like this where the existing turf has been laying its seed in the soil for decades.

Spreading cardboard.

Spreading cardboard.

To make this step of the installation process possible, Whole Foods Market provided recycled cardboard and refreshments for the workday while Bayview Green Waste donated two truck-loads of mulch. At 10 am on Saturday, once our people and materials were all in one place, the first item on the agenda was to lay down cardboard. It helps to think of sheet mulch like a layer cake.

The cardboard is the substance and it is necessary both in choking out weeds and feeding carbon to the soil through decomposition. Once every inch of the median was covered in cardboard so no weeds stood a chance, the next task was to pick up our shovels, rakes, wheel barrels, and especially our stamina in order to evenly spread out the two heaping piles of nitrogen-rich mulch. This is the frosting. It took about 4 hours to finish the entire process, with time mixed in for chatting and snacking. Most volunteers came at the beginning and saw the entire task through, but we were happy to have people stop by and help out in whatever capacity they could.

Spreading out the mulch over the cardboard.

Spreading out the mulch over the cardboard.

What was really the cherry on top of our sheet mulch cake was the number of people walking or driving by on the street who stopped to commend the work we were doing. One local resident from around the corner stopped to tell us that, “I used to have to pollinate the tomatoes in my garden with a tiny, little paintbrush. Now I have bees!” It is clear that the first median has touched a lot of people whether they enjoy the way it looks or they have noticed the abundance of pollinators now populating their once abandoned gardens. Check out the video below and you will find, the consensus is pretty simple; the Pollinator Boulevard is filling a need in the neighborhood and residents have a defined stake in its success.


After a productive day of expanding pollinator habitat, everyone was exhausted, but we will have plenty of time to recuperate until plants are ready to go in the ground. Sheet mulching requires time for decomposition and the thorough eradication of weeds before new plants can be positioned in the landscape, thus our next work party is scheduled for the Spring. This will be the final step of installation where the garden will truly come to life. We will keep you posted!

Stay tuned for a planting day work party this Spring. We would love your help!

Stay tuned for a planting day work party this Spring. We would love your help!



The Dolores Pollinator Blvd. is officially expanding!

Come join us for a Community Sheet Mulching Event on Saturday, October 1st from 10-2. We’ll begin the process of eradicating the dead turf and weeds from the second median at Dolores St. and 14 St. to make way for colorful, pollinator friendly, drought tolerant planting.

All are welcome! Invite family, friends, neighbors, and colleagues!

To learn more about the project, visit:

Questions? Contact:













We are very proud to announce that BASE has won a national award for the Roving Rangers, two bright and beautiful mobile park ranger stations currently serving communities in California. The American Society of Landscape Architects recognized our work on the Rangers with a 2016 Communications Honor Award, which honors achievements in communicating about landscapes and their value.

Made from retrofitted bread trucks and resembling food trucks, the Rangers are a thrifty, flexible and non-traditional approach to bringing parks to people—and encouraging more people to come to parks.

Besides celebrating the award at the 2016 ASLA Annual Meeting, Patricia will be speaking on a panel about Green Cemeteries: A New Paradigm for Public Open Space on Friday, October 21 from 8:30 AM – 10:00 AM. Don’t miss it!



These past two Fridays June 17th and June 24th from 4-7 pm, we had the pleasure of talking with the community about our latest project, Parklab at SF’s newest food truck park, SPARK Social SF. Parklab is a new interim use park that will activate a vacant 4-acre stretch of land running through the center of Mission Bay, one of San Francisco’s most rapidly growing neighborhoods. This new green space will serve as a social junction where people and place intersect. From it, we hope notions of community can continually be discovered. We spoke with a lot of people from various locations both locally and throughout the Bay Area!

During these events, we enjoyed the opportunity of gathering more insight as to what people would like to see in that space. Currently, we are in the early stages of ideation, and all input is appreciated. Eco hot tubs, pollinator gardens, community gardens, art residency yurts, community workshop spaces, an outdoor incubator kitchen, a roller rink, and rotating shop kiosks, are just a few of the many great ideas that we have heard from the community. Possibilities are endless!

On June 24th, we celebrated pollinator week by handing out wildflower seed balls in the form of Seedles to the community. Seedles are a mix of wildflowers that are pollinator friendly, such as California Poppy, Tidy Tips, Mountain Phlox and more! Each ball contains about 5-25 wildflower seeds! Pollinators, such as bees, birds, and butterflies are an extremely important part of our ecosystem, and we hope to spread the love and knowledge of these important creatures. By planting more wildflowers, and using permaculture principles we at BASE hope to help create as much healthy habitat as possible in our city in vacant and underutilized spaces. We also celebrated using chalk art as a medium for children of all ages to be a part of the action.



Natalie (designer at BASE) and Sara (summer intern at BASE)








Chalk art!

Drawing pollinators!



 Parklab Overall Concept Plan

Parklab Concept Plan Close up of block p-15.


Stay tuned in our journey to share your vision and get involved! We would love to see you at the next event.

We are pleased to announce that the two BASE-designed and -fabricated mobile visitors centers, LA Ranger Troca and the Roving Ranger, have been featured in the June 2016 issue of Landscape Architecture Magazine!


BASE Annual Report

Happy 2016!

We are excited to introduce our first ever BASE Annual Report! 2015 was a big year for us here at BASE. Our projects took us from the shores of Lake Tahoe to the national parks of Los Angeles, allowing us to create innovative and enduring places for thousands of folks from Oregon to Mexico. And we are loving every minute of it. We hope you will take a few moments to read about a few of our projects and accomplishments from 2015.
Annual Report Cover















Come join us and help plant pollinator habitat!

We’ll be gathering Saturday, March 12th at 10 AM in front of Whole Foods – Market Street to plant drought tolerant pollinator habitat at the Dolores St. Pollinator Blvd. We’ll be digging around in the mulch and planting colorful shrubs and perennials. If you’re in a rush, stop by to throw some Seedles. All tools will be provided by SF Public Works and snacks will be provided by Whole Foods Market – Market Street.

All are welcome. We hope to see you there!


What: Community Planting Day

When: Saturday, March 12, 10 am

Time: 10am – 3pm

Where: The median outside of Whole Foods Market – Market Street at 2001 Market Street, San Francisco.

What to Bring: Friends, gardening or work gloves if you have them



*Dolores Street Pollinator Blvd is part of Street Parks, a land stewardship program co-managed by Public Works and Parks Alliance that works with community members to convert City-owned parcels into green open space, verdant gardens, wildlife habitat, neighborhood gathering spaces, and more.


We are excited to share that our Bee Safe research has been featured in WLA Magazine!

The Bee Safe campaign was chosen as one of 16 research projects featured in the 21st edition of WLA Magazine, an online magazine by World Landscape Architecture. This issue, entitled Research and Policy, showcases studies and research by landscape architects on a wide range of topics from saving bees to sea change and rethinking dying shopping streets.

Check out the pages on the Bee Safe campaign below and the full issue of WLA21 here.