O'BRIEN | SiteArchitecture LLC is an Oklahoma-licensed landscape architecture studio consulting for architecture firms, public projects, and long-term site strategy.
From early concept through construction documents, we integrate site design so projects move forward without friction.
This isn't landscaping,
this is
Site Architecture
Site design should never be an afterthought. It dictates the fundamental relationship between an architectural project and its environment — governing every approach, user experience, and long-term performance outcome. By starting the dialogue early, we ensure your work is intentional rather than reactive. We trade patchwork for cohesion — creating a site that is fully resolved, not negotiated.
We integrate directly into architecture and engineering teams — providing landscape architecture where it is often missing or underdeveloped.
The goal is simple: reduce friction, improve coordination, and make projects easier to build.
We operate as an extension of your team — not an external add-on.
We also bring in-house aerial capability — UAS imagery, photogrammetry, and 3D site documentation — to support analysis, design, and inspections.
O'BRIEN | SiteArchitecture serves as Landscape Architect of Record, leading site design from early concept through construction documentation and coordination — carrying full professional responsibility for the outcome.
We translate vision into buildable drawings — aligning grading, circulation, planting, and materials so projects can move forward without delays.
If it needs to be built, resolve the site first.
Most communities operate without a long-term landscape strategy. Over time, that leads to reactive decisions, inefficient spending, and gradual decline.
O'BRIEN | SiteArchitecture works alongside boards and community maintenance teams to provide continuity — helping communities make clear, informed decisions that protect and improve the property over time.
Board members rotate. Institutional knowledge doesn't have to.
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The Community
Edinburgh is a gated neighborhood unlike most in Edmond. Its layout — a series of six-home cul-de-sacs arranged around a central green space one block wide and six blocks long — was designed to prioritize shared landscape over private yard. The homes are close together, the green space is generous, and the community is composed largely of retirees who care deeply about where they live and notice when things decline.
That green space is the heart of the neighborhood. What happens to it matters.
The Problem
Edinburgh Home Association had been spending money every year replanting the same beds. Annual color — seasonal flowers that look good in spring and are gone by fall — had become a recurring budget line with no long-term return. When board members changed, nobody questioned it. It was simply what you did.
There was no landscape plan. No standards to pass to a new board or a new contractor. No framework for deciding what to address first or why. The landscape was being maintained, but it was not being managed.
The Assessment
O'BRIEN | SiteArchitecture began with a full existing conditions assessment — walking every planted area, evaluating plant health and performance, and identifying where conditions were worst and where visual impact was highest.
The result was a 22-page written report accompanied by a 17-page catalog of every existing plant species on site. Together, these documents gave the board something they had never had: a clear, professional record of what they were managing, what condition it was in, and what it was costing them.
The assessment was accompanied by a 36×48 master plan rendering kept in the clubhouse — so residents could see the full scope of the design intent. Not just the board, but the community itself.
The Plan
The phased master plan was not a tear-it-out-and-start-over document. The goal was to design a new planting aesthetic within the framework of the landscape that already existed — transitioning annual color beds to perennial and shrub-based plantings that establish, fill in, and perform year after year without replanting costs.
Each phase was sequenced by a combination of condition severity and visual impact — the areas most seen, most used, and most in need of attention came first, so the community could see meaningful, visible progress with each phase.
Three Phases Completed
Phase 1 — Clubhouse Planting Beds
The beds surrounding the clubhouse were the first to be redesigned. As the community's primary gathering space, improving this area established the new planting aesthetic and gave the board early proof that the approach was working.
Phase 2 — Entry Gates and Monument Sign
The entry sequence — the gate islands and the monument sign planting — sets the first impression for every resident and guest. Redesigning these areas with a perennial and shrub palette brought consistency and permanence to what had previously been seasonal and forgettable.
Phase 3 — Greenspace Endcap
The large terminal planting bed at the end of the central green space is the visual anchor of the entire neighborhood. Redesigning this bed completed the primary visible sequence — arrival, entry, and terminus — giving the greenspace a defined beginning and end that the planting now reinforces.
On-Call Advisory
Beyond the installation phases, O'BRIEN | SiteArchitecture serves as the board's on-call landscape resource — reviewing irrigation concerns, interpreting soil testing results, and helping identify maintenance needs that fall outside the contractor's standard scope. When questions come up that the board does not know how to evaluate, there is a professional in their corner who does.
Where Edinburgh Is Today
Three phases of landscape improvements are in the ground. The annual color budget is being phased out. Each year the board returns to plan the next phase — not because they have to, but because the process is working and the neighborhood is visibly improving.
Edinburgh now has a documented master plan, a complete plant catalog, and a professional relationship that carries institutional knowledge forward regardless of who sits on the board next year. The landscape keeps getting better because the strategy behind it is sound.
Prairie Drift is O'BRIEN | SiteArchitecture's approach to ecologically informed planting design — drawing from the plant communities, climate patterns, and site conditions native to the southern plains. It is how we think about plant selection, palette building, and long-term performance in the ground.
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Carl O'Brien
PLA, ASLA — Principal Landscape Architect
Carl O'Brien is a licensed landscape architect and founder of O'BRIEN | SiteArchitecture LLC, a landscape architecture studio based in Oklahoma City. He holds a Bachelor of Landscape Architecture from Oklahoma State University and spent five years at a leading Oklahoma architecture firm, where he led landscape architecture efforts on civic, institutional, and commercial projects across the state before establishing O'BRIEN | SiteArchitecture in 2022.
Carl's consulting work centers on architecture and engineering teams that need a landscape architect who understands their pace, workflow, and project pressures. Working primarily in Vectorworks, he coordinates directly with design teams from schematic design through construction documents, operating as an extension of the team rather than an outside specialist brought in late in the process.
His approach is grounded in the belief that landscape is not decoration, but infrastructure for how a site performs, how people move through it, and how architecture is ultimately experienced. His intent is never to cover a building up, but to create the conditions where the architecture, site, and arrival sequence are more clearly revealed.
That same sensibility carries into his neighborhood and community work. Carl's earlier degree in psychology from OSU informs how he approaches boards, communities, and long-term planning — recognizing that successful landscapes depend not only on physical design, but on how people make decisions, build consensus, and care for places over time.
Beyond practice, Carl has served as an adjunct professor at Oklahoma State University, teaching Visual Communications and Design Studio III, and continues to be invited as a jury member for OSU's landscape architecture program.
Carl holds a Professional Landscape Architect license in the State of Oklahoma and is a Professional Member of the American Society of Landscape Architects.
"I have had the pleasure of working with Carl for the past several years as our neighborhood HOA decided to create and implement a long-term landscape plan for our green space. He did a great job of integrating the proposed new material with the existing look and feel of the overall space — always willing to come on site to answer questions and offer guidance. Having a long-term landscape plan has made a big difference to the neighborhood by eliminating costly annual planting and ensuring a cohesive appearance."
Barbra Mize
Edinburgh Home Association — Edmond
"We have enjoyed working with Carl on three projects at our home. We started with a fountain, planter, and hardscape area and liked the result so much that we were inspired to continue with Carl on two bigger projects. Even though we live in Tulsa, Carl is always available to discuss our wishes, make suggestions, and work with the installation crews to facilitate the construction of the project. From the beginning Carl has listened to us express our ideas and then presented a landscape design plan and plant palette that fulfilled our desires. The resulting projects are beautiful."
Gilcrease Residence
Tulsa, Oklahoma
Whether you are an architecture firm looking for a landscape architecture partner, a community ready to think strategically about your landscape, or a direct client with a site to resolve — we would like to hear from you.
O'BRIEN | SiteArchitecture serves clients across Oklahoma City, Tulsa, and Oklahoma.