Sowing the seeds of beautiful highways

Sowing the seeds of beautiful highways


Sowing the seeds of beautiful highways

Sowing the seeds of beautiful highways

By Laurie Merrill / ADOT Communications
September 1, 2020

When the season's right, you can’t drive on Arizona’s highways for long without noticing brilliant splashes of yellow, red and purple competing for appreciation along various roadside banks and in the medians. 

Depending on the season and the highway, drivers can see a profusion of penstemon, prickly poppy, purple owl’s clover and hundreds of other wildflowers in hues of green and orange along native trees bedecked in yellow and white blossoms.  

This native splendor is no accident. It’s the result of decades of trial and error, scientific know-how, and the care and leadership of LeRoy Brady, chief landscape architect for the Arizona Department of Transportation.

Brady, 79, has been with ADOT for as long as there has been an ADOT: 46 years.

“I have always loved plants of all types,” Brady said. “My earliest memories are of working with plants, picking berries, collecting plants, transplanting, planting seeds.”

Starting at age 8, he worked not only in his family garden but also aiding neighbors in Durango, Colorado, with landscaping and gardening. Brady graduated from Utah State University with a degree in landscape architecture and environmental planning.   

He starting making highways beautiful in Idaho before being lured away by ADOT in 1974. With a family in tow, Brady came as much for the proximity to his parents as for the challenge of populating Arizona’s highway banks with native vegetation requiring minimal water.

From tumble weeds to native plants

“We had tumble weeds, weeds and invasive species everywhere,” Brady said of highway landscaping at the time. Some banks were made of concrete, others planted with unsustainable grass and still others covered in weeds.

Brady’s unit began transitioning away from these plants in 1980 and by 1993 had gone with an entirely native selection, he said. Brady and colleagues plant an estimated 2,000 acres in any given year.

“We use native grasses, coneflower, yarrow, penstemon, desert marigold, brittle bush and purple treon (desert lupine),” to name just a handful. “The effort is to make it all sustainable.”  

ADOT’s highway areas are broken into environmental zones, and for each zone, a list of seeds has been developed.

“The seed mixture at Sunset Point is entirely different than in Quartzsite,” Brady said.

Each project utilizes seeds from 20 to 25 species, which include an array of annuals, biennials and perennials as well as cool-season and warm-season germinators.

Tilling, fertilizer and the proper nutrients are among 18 elements required for these roadside plants to grow.

A volunteer with a big heart

Brady hasn’t just beautified highways. He has also volunteered his time to improve the environment across Arizona by serving on the boards of a large number of organizations.

These include the Design Review Board, Parks Board for the City of Mesa, the Arizona Native Plant Society, the Arizona Chapter of the American Society of Landscape Architects, the Arizona Historical Advisory Commission, Boyce Thompson Arboretum, the Southwest Vegetation Management Association Board and Arizona Board of Technical Registration.

Brady has no plans to trade in his gardening tools just yet. It's not so much a point of pride but the delightful opportunity to sew the seeds of what he loves.

For ADOT freeway aesthetics are no afterthought

For ADOT freeway aesthetics are no afterthought


For ADOT freeway aesthetics are no afterthought

For ADOT freeway aesthetics are no afterthought

By David Woodfill / ADOT Communications
February 3, 2020

Designing a freeway includes quite a bit of thought about how it will look beyond the travel lanes. That's why we make sure Valley freeways have designs that reflect the history and natural beauty of the areas they pass through. 

The Loop 202 South Mountain Freeway is the latest reflection of that commitment. When designing the 22-mile freeway, ADOT took care in picking how sound walls, bridges and more would look, down to the lines, paint colors, landscaping and ground cover, including land-form graphics. 

As we shared last week, ADOT's designers drew inspiration from the work of modern architect Frank Lloyd Wright, architect, urban designer and artist Paolo Soleri, cholla cactuses, agriculture, the Salt River, South Mountain and more. You'll also see similar themes reflected in the choice of vegetation using, in some cases, native plants that were removed from the freeway's path, kept in temporary nurseries and replanted. 

ADOT developed these concepts, which were presented for public input, in collaboration with the Frank Lloyd Wright Foundation and Cosanti Foundation.

“Design choices are an important part of providing quality freeways for today and for future generations,” said LeRoy Brady, ADOT’s chief landscape architect. “They enhance the experience of those who use the South Mountain Freeway.”

Next time you're heading down the South Mountain Freeway, we hope you'll take the time to appreciate how its design incorporates flavors from different areas along its path. 

ADOT freeway landscape designer wins lifetime achievement award

ADOT freeway landscape designer wins lifetime achievement award


ADOT freeway landscape designer wins lifetime achievement award

ADOT freeway landscape designer wins lifetime achievement award

By Angela De Welles / ADOT Communications
August 28, 2019

ADOT’s Joseph Salazar was honored recently with a lifetime achievement award from the American Society of Landscape Architects Arizona Chapter.

Salazar, who has been with ADOT for almost 30 years and serves as landscape architectural project design manager for the Roadside Development section, said the award came as a complete, wonderful surprise.

The award noted Salazar’s attention to context-sensitive design and his role in designing distinctive aesthetic patterns on the freeway walls and bridges as well as developing landform graphics, which use granite in contrasting colors to create patterns and designs onto the ground plain.

Now, months later, Salazar says he’s “still up on cloud nine” because of the honor, and even though the award was for a lifetime of achievement, he looks forward to exploring new methods and using alternative materials for future artistic designs and landscapes.

When asked to name his favorite project, Salazar said, “It’s always the next one.” However, he did admit his work on the State Route 143/Sky Harbor Boulevard traffic interchange is very special to him.

“It’s the gateway not only into the Valley but the whole state,” he said. “It introduces people who are visiting our state to Arizona.”

The design work currently happening on the Loop 202 South Mountain Freeway is also something he’s very proud of and is a perfect example of the context-sensitive design that ADOT has become known for.

“We developed character zones to represent the different environments that the freeway goes through,” he said. “Each area has its own theme, but there’s a common pattern that ties it all together.”

When explaining why roadside development and landscape design are so valuable and worthwhile, Salazar said it’s because it makes projects more appealing and acceptable to the public.

“After all, none of our communities want to live, work, or drive along ugly highways,” Salazar said. “Our freeways are a reflection of who we are in this state. We’re working alongside our various engineers and we take what they’re developing and make it beautiful. I’m very grateful to our engineers, management, consultants, contractors, and of course our local communities for their support through the years to make our freeway system the best there is around.”

Saguaro cactuses relocated for South Mountain Freeway

Saguaro cactuses relocated for South Mountain Freeway


Saguaro cactuses relocated for South Mountain Freeway

Saguaro cactuses relocated for South Mountain Freeway

November 21, 2016

By Dustin Krugel / ADOT Communications

The Arizona Department of Transportation has transplanted thousands of saguaro cactuses during construction projects. Through decades of practice, the agency has developed many successful techniques for salvaging these iconic cactuses.

Last week, I shadowed a five-man crew, working on the Loop 202 South Mountain Freeway project to learn more about this process. In less than two hours, a team of landscapers dug up and moved a 10-foot-tall saguaro near Pecos Road to its home for the next three years: a nursery that will hold salvaged plants until they are replanted prior to the freeway opening by the end of 2019.

The plant salvage process started months ago when landscapers investigated the health of native plants in the freeway's path. In the case of cactuses, those that were good candidates for relocation were tagged. Cactuses that weren't deemed healthy or were growing in rock or other conditions that make them unlikely to survive transplantation aren't being moved.

With the aid of a large backhoe and several shovels, the crews I shadowed carefully dug up the saguaro, exposing the roots. While this was occurring, one crew member sprayed the ground with water to keep dust down. A truck equipped with a boom lift and cradle secured the saguaro in an upright position. Padding in the cradle ensures that the cactus isn't scraped and scarred during the move.

The truck boom then lowered the saguaro into its temporary home.

Workers then dug up a hole and placed the saguaro facing the same direction as it was before and at the same depth as its former home. ADOT has learned that planting a saguaro too deep can affect its survivability. At the base of the roots, the crew added sulfur and sand to help the saguaro take root. Finally, they compacted the ground around the saguaro.

In the next three years, landscapers will monitor the saguaro and spacing between the ribs, making sure it has enough water. When the freeway is nearly complete, the saguaro will be planted within the freeway footprint and will add to the scenery for decades to come.

Temporary digs for plants that will grace South Mountain Freeway

Temporary digs for plants that will grace South Mountain Freeway


Temporary digs for plants that will grace South Mountain Freeway

Temporary digs for plants that will grace South Mountain Freeway

November 4, 2016

By Dustin Krugel / ADOT Communications

Crews are making significant progress relocating hundreds of native plants, trees and cactuses in the path of the Loop 202 South Mountain Freeway. They are quickly filling a temporary nursery that will be home to the plants until they are placed along the freeway, which is scheduled to open in late 2019.

As of this week, more than 400 palo verde, mesquite and ironwood trees and 300-plus barrel cactuses had been moved to the nursery. 

The first saguaros and ocotillos will be arriving soon. In all, more than 1,000 plants will be salvaged.


As we shared earlier this week, this plant salvage operation has workers carefully digging up the plants and boxing them to preserve their roots.

The plants are getting special care at the nursery, including watering from an irrigation system.

The nursery, which is about the size of two football fields, is in an area of ADOT right of way along the Pecos Road alignment that will be used for water-retention basins.

Native plants being relocated from South Mountain Freeway path

Native plants being relocated from South Mountain Freeway path

I-17 101 traffic interchange

Native plants being relocated from South Mountain Freeway path

Native plants being relocated from South Mountain Freeway path

October 31, 2016

PHOENIX – When the Loop 202 South Mountain Freeway opens, many of the trees, cactuses and other plants that will blend into the surrounding landscape will be transplants from the freeway’s path.

Crews have started removing native vegetation, including saguaros and palo verde trees, in the 22-mile corridor so it can be cared for during construction and eventually replanted alongside the freeway.

For more than 30 years, restoring native plants has been an integral part of many Arizona Department of Transportation projects, including the recent expansion of the Loop 303 in the West Valley and the Loop 101 Pima Freeway widening in Scottsdale.

Doing so is good for the environment and makes roadsides more appealing, said ADOT Chief Landscape Architect LeRoy Brady, who worked on ADOT’s first plant salvage effort in the mid-1980s along State Route 87.

“ADOT takes great pride in maintaining the highway scenery by preserving some of these long-standing plants that are part of Arizona’s history,” Brady said. “ADOT dedicates funding for this work, and it helps promote sustainable practices and contributes to the long-term viability of the desert ecosystem. An added benefit is the local communities really seem to support this work.”

In September, landscapers took an inventory of more than 1,000 trees, cactuses and native plants along the Pecos Road alignment that are candidates for plant salvage. Other types of plants that will be salvaged include ironwood and mesquite trees, and ocotillo and barrel cactuses.

Last week, crews began transplanting some of these trees and cactuses, which can weigh up to 2,000 pounds, with the aid of heavy equipment. These will be moved over the next two weeks to a nursery in ADOT’s right of way, as has been done on other Valley freeway projects.

The nursery, which includes an irrigation system, will serve as the plants’ temporary home until they are transplanted upon completion of a freeway segment.

Landscapers decided which plants to salvage based on factors including the species, size, health and aesthetic qualities. Plants that aren’t likely to survive the relocation will be permanently removed.

The 22-mile freeway, expected to open by late 2019, will provide a long-planned direct link between the East Valley and West Valley, and a much-needed alternative to Interstate 10 through downtown Phoenix.

For more information, visit

ADOT completes replanting of saguaros on Loop 101 project

ADOT completes replanting of saguaros on Loop 101 project

I-17 101 traffic interchange

ADOT completes replanting of saguaros on Loop 101 project

ADOT completes replanting of saguaros on Loop 101 project

August 24, 2016

SCOTTSDALE – Drivers on the now-wider Loop 101 (Pima Freeway), where new lanes have been added south of Shea Boulevard, may also have noticed construction crews working in recent months to transplant large saguaros, other cactuses and trees that had temporarily been stored in nurseries near the freeway. Many of the tall saguaros have been around longer than Arizona has been a state.

As part of the Arizona Department of Transportation's $74 million project to improve an 11-mile stretch of Loop 101 between Shea Boulevard and Loop 202 (Red Mountain Freeway), the project team early on salvaged more than a thousand plants. That includes approximately 400 saguaros that are now back as part of the desert-based landscaping next to the freeway.

ADOT worked closely with the Salt River Pima-Maricopa Indian Community and the city of Scottsdale on the plans for salvaging, storing and transplanting the cactuses and other plants, including thorny ocotillos and ironwood trees.

“This restoration work is challenging but also very rewarding because many of the saguaros are more than a hundred years old and it’s great to have them in place as an iconic symbol of Arizona,” said ADOT Landscape Construction Supervisor Richard Adamson.

The plant-restoration work next to Loop 101 ramped up this summer, with crews using heavy equipment to transport individual plants from each of the nurseries to a location mapped out for their replanting. In addition to the plants that were saved over the last two years, crews also are adding approximately 10,000 new shrubs, trees and cactuses along the freeway.

“We’ve learned a lot over the years about including plant restoration in our freeway-improvement projects,” said Madhu Reddy, district engineer for ADOT’s Central Construction District in Phoenix. “Local communities support these efforts and we receive compliments from local residents and Valley visitors who like what they’re seeing.”

Preserving, relocating native plants a big part of ADOT's Loop 101 project

Preserving, relocating native plants a big part of ADOT's Loop 101 project


Preserving, relocating native plants a big part of ADOT's Loop 101 project

Preserving, relocating native plants a big part of ADOT's Loop 101 project

June 23, 2016

By Caroline Carpenter / ADOT Communications

What weighs up to 5,000 pounds, is more than 100 years old and can be more than a little prickly about moving?

Give up?

It’s one of the hundreds of saguaros in temporary quarters next to the Loop 101 Pima Freeway project.

As portions of the project wrap up, crews have been working to move more than 1,000 saguaros, along with native trees, to new locations.

Transplanting the massive desert plants isn’t an easy task. The video above explains what goes into maneuvering these thorny giants.

ASU landscape architecture students get Loop 101 tour

ASU landscape architecture students get Loop 101 tour


ASU landscape architecture students get Loop 101 tour

ASU landscape architecture students get Loop 101 tour

May 5, 2015

ADOT Project Landscape Architectural Designer Joe Salazar shows paint samples to the students.

Learning doesn’t always have to take place inside of a classroom, sometimes it can happen safely near the side of a freeway!

That’s where a group of ASU students received a “behind the scenes” tour, packed with details on how ADOT’s Roadside Development section provides landscape, architectural and environmental technical design direction for projects statewide.

After sitting in on a morning construction meeting, the students – all juniors who are working toward their degrees in landscape architecture – were given a tour of the Loop 101 improvement project. The project, which will add new lanes in both directions of Loop 101 between Shea Boulevard and Loop 202 in the Scottsdale and Salt River Pima-Maricopa Indian Community, proved to be an excellent one to showcase.

“It’s an ideal example of all the aspects ADOT gets involved with … it contains everything,” said ADOT Project Landscape Architectural Designer Joe Salazar.


Just north of Chaparral Road, the students stopped to see the project's plant salvaging operation.

Yuri Lechuga-Robles, an ADOT intern with Roadside Development and also a student in the ASU class, helped to initiate the tour and agreed that the project was a good one to highlight.

“The project is one that the students were aware of, but probably never thought they’d be able to see from the inside. For that reason, it was a really good choice,” he said, adding that before beginning his internship at ADOT, he didn’t realize how much input goes into a project. “For me, the tour was an opportunity for my classmates to get a glimpse of what the projects are all about … just to have them see the size of the team that it requires was important.”

The first stop on the tour was off Loop 101, just north of Chaparral Road. Here, the students saw the project’s plant salvaging operation, where the cacti and trees that were removed for construction live for the project’s duration. The thousands of Ironwoods, Ocotillos and Saguaros are watered and cared for in the makeshift nursery until they can be replanted when the project nears completion.

ADOT’s Chief Landscape Architect LeRoy Brady told the students that many factors are vital when replanting salvaged Saguaros. Research has shown that Saguaros fare much better if they’re replanted at the same, exact depth they were originally growing – even just a few inches deeper can result in loss, he said.


Thousands of Ironwoods, Ocotillos and Saguaros are watered and cared for in the makeshift nursery.

The next stop was off the freeway at McDonald Drive for a look at the project’s paint pallet and decomposed granite samples. Salazar explained how ADOT worked with the community to determine the colors, which are all earth tones.

The tour concluded with a review of the project’s architectural design at the 90th Street bridge and a look how surrounding neighborhoods can be integrated into ADOT projects using walkways, bike lanes, equestrian trails and landscaping.

That community collaboration was definitely a big theme for the day…

Before the tour even began, students got the chance to hear from representatives from the Salt River Pima-Maricopa Indian Community.

SRPMIC Director of Community Relations Janet Johnson talked to the students about the meaning behind some of the symbols and artwork being used on the project. Terrollene Charley, of the SRPMIC Planning Services Division explained it is important to the community that the project’s landscaping reflects the indigenous desert surroundings.

The community collaboration made an impression on the students.

Cesar Del Castillo said he especially liked seeing how the surrounding communities play a part in the project.

Student Shane Ohlhausen agreed, saying he enjoyed the exposure to public works and being able to hear from the SRPMIC.

“It was a good experience,” he said.

Science of Transportation: Calcium Carbonate testing

Science of Transportation: Calcium Carbonate testing


Science of Transportation: Calcium Carbonate testing

Science of Transportation: Calcium Carbonate testing

July 1, 2014

Plants won’t grow if they’re rooted in the wrong soil – no matter how green your thumbs are.

That’s why ADOT makes sure its topsoil is suitable for good growth...

Before you start asking why ADOT, a department responsible for building and maintaining state highways, would put time and money toward soil and plants, let us just say that landscaping serves a very practical role beyond making things look prettier.

According to the ADOT Construction Manual, “Functional plantings serve to improve traffic guidance, reduce headlight glare, provide safety features, reduce pollution, provide view and wind screening, control erosion, act as a sound barrier and contribute to improved aesthetic values.”

Topsoil testing

The topsoil (top two feet of soil) that’s used on ADOT projects in urban areas must meet certain specifications to make sure that plantings will have a chance to thrive. Before a source of topsoil is accepted on an ADOT project, an analysis is completed to check pH levels, soluble salts, exchangeable sodium and other characteristics.

We’re not going to focus on every single test in this blog post (that would take too long and there are good soils books that do just that!). Today, we just want to explain how topsoil is tested for Calcium Carbonate.

As you can see in the video above, ADOT’s Materials Chemistry Lab starts with a gram of soil.

After adding a Hydrochloric Acid solution to the soil (this ensures the complete decomposition of the Calcium Carbonate), the mixture is filtered. Next, a drop of Phenolphthalein Indicator is added (this is a chemical that will change color depending on the composition of what it mixes with).

Now, a Sodium Hydroxide Solution is measured into that solution until it turns to a pinkish color. The amount of Sodium Hydroxide Solution necessary for that reaction to take place is recorded and used in an equation that shows the percentage of Calcium Carbonate in that soil sample.

Isn’t science amazing?

In order for topsoil to pass for use on an ADOT project, six samples can’t average more than 8 percent Calcium Carbonate.

Calcium Carbonate isn’t bad – a certain level of it is needed in soil – you just don’t want too much of it, otherwise plants are going to have a hard time.

“It can bind the soil particles together so tightly that water can’t penetrate,” said ADOT’s Chief Landscape Architect LeRoy Brady. “If the percentage of Calcium Carbonate is too high, you’re not going to get infiltration of what little rainfall we get.”

Brady says a high presence of Calcium Carbonate can also make other micronutrients not as available.

If a topsoil source does not meet specifications, ADOT can reject it and require that the contractor use another source. In some cases, ADOT can require that a contractor treat the soil to fix the problem.

The end goal for all this testing is to make sure that the landscaping lasts.

"We’re looking at the long term," Brady says. "We want to make it as sustainable as possible."

According to ADOT Chemist Jeffrey Faulkner, the ADOT lab tests approximately 100 topsoil samples for Calcium Carbonate each year.

You might think that highway construction is all about big machinery, heavy-duty vehicles, massive structures and materials by the ton – but it’s not. Sure, those are important, but when it comes to building a road, science plays a strong role too. In fact, the work ADOT does off the project site and inside a lab is so significant that we are highlighting it here on the blog with a new series we’re calling, The Science of Transportation.