3 landscape maintenance tasks regularly performed by ADOT crews that you might not know about

3 landscape maintenance tasks regularly performed by ADOT crews that you might not know about


3 landscape maintenance tasks regularly performed by ADOT crews that you might not know about

3 landscape maintenance tasks regularly performed by ADOT crews that you might not know about

January 18, 2013

If you liked this list we shared last month, you’re in luck today…

That’s because we have a similar one to show you. Except instead of focusing on electrical maintenance tasks, this list examines landscape maintenance and three related responsibilities ADOT crews regularly tackle that you may not know about…

1) Landscape care and maintenance
Many people might not realize that ADOT crews handle landscape maintenance at all, so let us first define a few of the basic duties.

In the Phoenix district alone, there are 220 miles of landscaped areas that sit adjacent to the ADOT freeway system.

Crews care for the plants and irrigation systems. They also have to worry about weed control, erosion, slope repair, graffiti abatement and litter.

Then there’s the land along the state highway system that’s not landscaped. These spaces are typically in the state’s rural areas and contain natural vegetation. ADOT crews maintain the native vegetation to make sure it doesn’t interfere with the roadways. That general maintenance includes weed control, mowing and basic upkeep – there is no irrigation to be maintained in these areas.

2) Dealing with technology
“Every single plant out there (within ADOT’s landscaped areas) has an irrigation emitter and buried underground are miles and miles of pipes that bring water out to those plants,” said ADOT Roadside Maintenance Manager Mark Schalliol.

He explains that the emitters are “complicated pieces of plastic” controlled through a radio network that allows ADOT crews to water plants remotely.

The system also gives Schalliol and his crews the ability to conserve water and quickly tell if an area is being overwatered.

“We have an extensive formula for watering plants,” he said. “We’re conscious of the water.”

Newer technology is being incorporated into projects where appropriate, said Schalliol, explaining how moisture sensors are now being used on two recent landscape projects. These sensors are activated by soil moisture and allow ADOT to monitor and control irrigation in response to soil conditions, irrigation and precipitation.

“We are trying these out as another way to monitor and control irrigation,” he said.

3) Landform graphics
Crews from the ADOT Landscape Section take care of all the landform graphics, too.

“Our biggest issue with those is when errant vehicles drive off the roadway,” Schalliol said.

Besides making sure the graphics keep their shape, crews spray regularly for weed control.

“People don’t like looking at weeds,” he says.

There’s more…
This is not an exhaustive list of all the maintenance duties performed by the ADOT Landscape Section crews, but, like with our last list, we hope it gives you a better look at some of the “unseen” tasks being performed by our crews every day.

Landscaping research earns honors

Landscaping research earns honors


Landscaping research earns honors

Landscaping research earns honors

November 6, 2012

Landscaping is an important element in roadway design.

Successfully transplanting a cactus from one spot to another takes more than just a green thumb…

In fact, as one ADOT study shows, many factors can affect whether or not a plant will survive after transplantation.

But, before we go any further on that study, let us first quickly explain why we’re blogging about plants instead of our more typical topics – you know, roads, bridges and dirt.

It’s because landscaping is an important element in roadway design – landscaping creates a sense of place and helps make the right of way area compatible with its surroundings.

And, we actually have blogged about it a few times before – an overview of why ADOT salvages and transplants cacti and other plants can be found in this blog post from last year.

OK, back to the study…

It focused on Saguaros and, along with a report on Ironwood tree salvage, recently was awarded honors from the American Society of Landscape Architects for its findings!

“The award recognized that we did some research that’s valuable to the industry,” said ADOT’s Chief Landscape Architect LeRoy Brady.

Brady says he and his team knew a lot about effectively transplanting Saguaros and Ironwoods, but wanted to research ways to increase the plant survival rates.

That’s when they proposed the research project.

Through the bid process, contractor Logan Simpson Design started studying projects going back at least 10 years, Brady said.

The researchers looked at characteristics shared by the Saguaros that survived being replanted.

What they found, according to Brady, was that the cacti with the highest survival rates were replanted as spears – before they developed “arms.” And, the research discovered, Saguaros did better if they were replanted at the same, exact depth they were originally growing. Any deeper, even by just a few inches, says Brady, could impact a plant’s water intake.

“We found out it makes a lot of difference,” Brady said. “The (cacti) that were transplanted continued to thrive and survive if they were replanted at the same depth.”

When it came to Ironwood trees, Brady says he and his team already knew that Ironwoods had a better survival rate if they were transplanted during warmer seasons, but construction schedules don’t always allow the transplants to occur at a specific time.

“We couldn’t always transplant when we wanted to,” said Brady, adding that the research confirmed their method of keeping roots warm with a compost mixture was really effective in ensuring the Ironwoods survived after replanting. “It kept the roots 15 degrees warmer and increased the survival rate.”

Why the research matters
Brady says it’s smart to research new methods and take time to learn about the most effective ways of keeping plants alive…

“It makes it so that we can improve the salvage specifications and transporting details, along with how they’re to be treated when they’re salvaged and replanted,” he said. “That way we’re maximizing the return on what taxpayers spend.”

Better methods also help keep Arizona’s landscape looking beautiful.

“Our desire is to have that (rural) highway section blend in with the surrounding area,” Brady said. “It makes a lot of sense to transplant the native plants so that section maintains its beauty and recovers from that construction.”

ADOT maintenance crews work through the monsoons

ADOT maintenance crews work through the monsoons


ADOT maintenance crews work through the monsoons

ADOT maintenance crews work through the monsoons

July 31, 2012

A look at erosion caused by a recent storm.

Ever survey an Arizona freeway during a monsoon? If you have, you’re likely to have seen debris in the roadway, landscapes in disarray, damage and even flooding…

Now, have you ever wondered who gets to tidy that mess?

You guessed it…we do! Or, more specifically, ADOT’s various maintenance crews are responsible for cleaning up after a storm.

“The monsoons definitely keep us jumping,” says Highway Operations Supervisor Jerry Turner.

Turner recalls a recent storm that rolled through the East Valley about three weeks ago, leaving mudslides on the Loop 202 (Santan) and flooding in an area on the US 60.

“You can only be in so many places in one time,” said Turner, adding that in severe weather conditions, he can call in for backup from other maintenance orgs.

A little bit about the maintenance crews (or orgs)...

Each org is responsible for a geographic area and each employee within that org is responsible for large stretches of roadways within the area. These same employees also make up ADOT’s ALERT team.

Typically, they maintain the roads – fixing things like damaged guardrails and making pavement repairs.

But, during severe weather or major incidents on the freeway these maintenance crews put in hours making sure the road is safe and clear for drivers.


Erosion along the roadway - the result of an East Valley monsoon.

ADOT Maintenance Superintendent Craig Cornwell says during and after a storm, ADOT maintenance crews typically run into plugged storm drains filled with silt and leaves.

There's often damages due to erosion along the roadways, which sometimes creates a hazard on the roadways, needing immediate attention to address safety concerns for the traveling public.

“They’re using dump trucks, loaders and skid-steers (small loaders),” Cornwell said. “The equipment they need to utilize just depends on the rainfall.”

What drivers can do 
Drivers are always urged to use caution while driving in inclement weather. Cornwell says that drivers can call 911 to report a serious storm-related driving hazard in the road.

Turner advises drivers to slow down and give maintenance crews some room to work!

“Be patient,” Turner said. “When you see us working in the middle of a monsoon, we’re not there because we enjoy being in the rain, we’re there because something’s wrong.”

One last thing ...
You knew we wouldn't be able to end a weather-related blog post without reminding you at least once to Pull Aside, Stay Alive!

Green dirt has nothing to do with St. Patrick's Day

Green dirt has nothing to do with St. Patrick's Day


Green dirt has nothing to do with St. Patrick's Day

Green dirt has nothing to do with St. Patrick's Day

March 16, 2012

This dirt isn't green for St. Patrick's Day ... but there is a good reason for its hue!

We won’t blame you if you see this green slope at the Loop 303 and US 60 (Grand Avenue) and think it's part of a St. Patrick’s Day stunt, but we promise this is no gimmick!

The mound of dirt is green for good reason, albeit one that has nothing to do with tomorrow’s holiday …

ADOT crews just seeded it with a wonderful mix of desert flowers and groundcover plant material.

The seed mixture is actually sprayed on and has an all-natural green dye in it. This dye helps whoever is doing the spraying make sure they get full coverage. In time, the dye will fade, so the slope won’t be green forever!

If we get some nice spring rains, we should see things blooming and growing on the slope in about 45 days.

About now, you might be wondering what this dirt mound is doing ... just sitting there. Maybe you're also asking why ADOT goes to the trouble of seeding slopes like this one.

Well, as part of the Loop 303 Improvement Project, crews had to excavate and haul about 150,000 cubic yards of dirt away from the roadway alignment south of US 60 so bridges could be built at Waddell and Cactus roads.

They hauled the dirt to this location just for the time being.

In the future when it comes time to build the interim traffic interchange at US 60 and Loop 303, this dirt will be used during construction.

But, by seeding it now ADOT is able to control dust. The vegetation that grows will cover the soil and prevent dust (landform graphics work in a similar manner). Seeding also helps prevent erosion.

So, even though there’s no St. Patrick’s Day connection, we’ll take this chance to wish you a little luck of the Irish anyway!

Landform graphics help with dust, erosion (and they look nice, too)

Landform graphics help with dust, erosion (and they look nice, too)


Landform graphics help with dust, erosion (and they look nice, too)

Landform graphics help with dust, erosion (and they look nice, too)

October 6, 2011

Crews work on the large landform graphics along I-17.

As ADOT employees, we naturally get a lot of transportation-related questions thrown our way by friends and family... it’s just something that comes with the job!

By far, one of the most frequently asked questions has to do with HOV lanes and why ADOT builds them after the freeway is constructed (we answer that one here, by the way).

But, another question we regularly get focuses on the rock landscaping surrounding our Valley freeways.

People want to know why we don’t just use trees and shrubs instead of rock. Others wonder why we landscape the area at all.

Well, here’s the answer...

The main purpose of all freeway landscaping is really a practical one ... it helps control erosion and dust.

According to ADOT’s Chief Landscape Architect LeRoy Brady, anything that breaks up the rainfall (such as rock landscaping) or has a root system and holds soil together is going to help handle erosion.

As for dust control, Brady says rock landscaping and other types of plant-based landscaping help simply by covering the dirt.

“Because you don’t have bare soil, you don’t have the dust. It eliminates the dust source,” he said.

The type of rock that’s used matters, too.

Brady says his department sponsored a study that researched what size and grade of rock would work best for controlling erosion. The study was completed about 23 years ago, but the information is still used today.

Not only does landscaping help with erosion and dust, it has the added benefit of improving the aesthetics along freeways!

Rock landscaping is less expensive to maintain than planting and trimming trees and shrubbery... and rocks don't exactly require a lot of water.

ADOT works with the local communities to determine how to enhance the scenery along the freeways. Take for example the landscaping project along the recently upgraded I-17 in the north Valley.

ADOT worked with the city of Phoenix to create the landscaping theme and settle on designs, which are created to reflect Arizona's heritage and environment.

Brady says "context-sensitive design" is an effort in transportation to design and construct environmentally sound projects that fit and relate to the community, “instead of something that’s foreign and has no relationship.”

Along I-17, great care was taken to create designs that really fit the community.

About 15 colorful landform graphics made of crushed granite have been created for the project. There are a few Gila Monsters that have now taken shape at the Carefree Highway interchange and along the slopes at the Jomax Road interchange there’s a design patterned after a Hohokam water bowl.

It’s a challenging prospect to take a landscaping pattern from paper to the extra-large canvas of a freeway slope...

The process starts with site visits. Crews use flexible PVC piping and rope to set patterns before using spray paint to outline the design on the ground. Metal edging is then used to create the borders for the different sections of the colored rock and then the rocks are put in place.

Landform graphics and rock landscaping aren’t the only affordable and sustainable options for our freeways.

The location of the freeway often plays a role in determining what type of landscape to go with, as it did on a recently completed stretch of Loop 303.

There’s a lot more to freeway landscape design that we’ll cover in future blog posts. In the meantime, check out ADOT’s Roadside Development Web page.

Enjoy the view - trees and cacti replanted to maintain the scenery on Loop 303

Enjoy the view - trees and cacti replanted to maintain the scenery on Loop 303


Enjoy the view - trees and cacti replanted to maintain the scenery on Loop 303

Enjoy the view - trees and cacti replanted to maintain the scenery on Loop 303

May 3, 2011

Cacti and trees replanted along the 303

This slideshow will give you an idea of how many cacti and trees were replanted along the new stretch of the Loop 303 last September.  The steps involved in removing just one saguaro from the on-site nursery and replanting it next to the road could sometimes take more than one hour. 

Who says constructing a freeway through a beautiful desert expanse has to spoil the view? 

Once the new stretch of Loop 303 opens this month, motorists will see for themselves that great care was taken by ADOT and its project partners to keep the scene as pristine and seemingly untouched as possible.

Native desert plants that lived in the path of the new freeway were not just pulled up and thrown away – they were uprooted, cared for during freeway construction and then replanted alongside the new road.

Crews began by taking an inventory of all the plants surrounding the 14-mile stretch of highway. There were saguaros, barrel cacti, several other cactus varieties, ocotillo, mesquite, ironwood and palo verde trees to contend with.

Landscapers decided which plants to salvage based on a variety of factors, including the plant’s species, size, health and aesthetic qualities. The saguaros and some of the other cacti are designated by law as protected, which means they cannot be allowed to succumb to construction projects.

A total of about 6,900 cacti and nearly 1,000 trees were tagged, dug up in such a way to preserve their roots and carefully replanted in three nurseries located on the construction site – the nearby location was good for the plants because they were already used to the site’s soil conditions.

Special care was taken to help keep the plants comfortable in their new, temporary home. Gravity-fed water systems were set up in the nurseries to ensure the plants thrived.

To assist in the transition back to their permanent spots along the 303, contractors saved the top layer of native soil from the roadbed and applied it to the slopes where a majority of the replanting occurred.

The forethought paid far, there has been a 90 percent survival rate for all the plants.

Outside contractors will care for the plants for the next two years. During that time, there also will be a temporary watering system in place alongside the freeway.

After the two years are up, the irrigation system will be taken out and the plants should be ready to make it on their own. The cost savings associated with this project include not having to install granite mulch, new plants and underground irrigation pipes and controls.

ADOT’s Chief Landscape Architect LeRoy Brady says he’d like to issue a challenge to people to watch as the vegetation stabilizes and adds to the area aesthetically.

He says that in addition to the replanting, all medians and roadsides have been hydro-seeded with 20 different species of plants – that means the area will continue to change, develop and grow more beautiful over time!