Museum Grounds and Sculpture Gardens


By Steven R. Keller, CPP

Each industry has its trends and "buzzwords."

Security is no different. Just a few years ago, everyone in our industry began to

talk about "security design." The security manager was suddenly expected to

become involved in advising architects and "owners" (the word used by

architects to refer to your company's top management) on how buildings should

be designed so that security can be assured. This trend was more than just a

passing fad. With the involvement of security managers in security design,

architects and building owners recognized that security directors had something

unique to offer to the planning process.

Security directors had finally "matured" as a group to win recognition by other

professionals. This was a major step forward for the security profession and for

us as individual professionals. Unlike past years when the security manager was

merely a chief guard, designated as being "in charge" solely due to his/her

seniority, our superiors recognize our accomplishments and technical knowledge,

and call upon us to serve in a more important advisory role. A major landmark

has been achieved by our profession.

Today, we as security professionals are called upon to play an important role in

other technical areas as well. One of those emerging areas is "landscape

architecture." Why landscape architecture? The involvement of security

managers in fields like computer security is obvious and logical, but what is there

to landscape architecture that requires our involvement? Why is this such a hot

topic? What influences an industry and causes trends like this to develop?

Over the past several years, building owners--the people we work for-- have

found themselves involved, more and more, in litigation, which has resulted from

a foreseeable or allegedly foreseeable crime against visitors on their property.

Someone enters the grounds of a building, is attacked, robbed or raped, and the

owner, architect, and security manager are threatened with a lawsuit. As the

trend develops to hold companies responsible for foreseeing crime on their

property, who else is more qualified at the task of evaluating the security of an

area than the security professional responsible for protecting that area?

So, we find that not only are companies dressing up their exteriors with

landscaping, at the same time, courts are holding owners responsible for

foreseeing crime on their grounds and taking steps to prevent it. More important,

when landscaping creates conditions which contribute to the loss of security on a

site, the potential for monetary loss in a suit can be great.

There is another trend that affects us as well. Technology has made it possible

for us to analyze landscaping and other construction details on a specific site,

and to determine the effects of bomb blasts and other similar events through the

use of computer-aided analysis. Security technology breakthroughs are not

uncommon. At a time when the threat of crime and terrorism is great, technology

that helps analyze landscaping, building design, and composition with the goal of

preventing bomb blast damage or other dangers by criminals is quite welcome.

Today, security directors and managers are being consulted more often on

interior and exterior security design. This means that we must know about

landscaping as it relates to security if we are to fulfill expectations of our

superiors who call upon us for advice.

For the purpose of this presentation, landscape architecture deals with the

design of a building's grounds for the purpose of aesthetics, preservation,

restoration, or other goals defined by the owner. When an owner decides that the

exterior or interior landscape needs to be changed, a landscape architect is

called in. The architect analyzes existing landscape elements or features such as

plantings, access means--paths and roads--topography, water features, lighting,

structures, grades, and new landscape requirements or elements, and develops

a proposed design. Usually, he/she is working with a program provided by, or

developed with the advice of, the owner. The program is an outline which

discusses how the landscape will be used, who will have access to the space,

what function it will fulfill, what image it will convey, etc. Is the landscape solely

for aesthetics? Does it serve a function, such as providing a park or recreational

space? For years, landscapes surrounding commercial buildings were solely for

aesthetics. Rarely was there ever any mention of security in the program. This

means that there wasn't much concern by the architect for building security into

the space. From here, it was usually all down hill.

The architect, if not aware or concerned about safety and security, will design in

security problems or ignore opportunities to improve security. With your

involvement, it no longer has to be that way. When you learn of a landscape

project on your company's property, you must become involved from the

beginning. It should be your primary goal to make an impact on the program that

is being developed. The building's management and the architect should become

aware of the positive impact that you can make by designing good security into

the landscape plan, and the negative impact that you can help avoid by

designing out security problems.

Your next step should be to undertake a security risk assessment to determine

the risk that exists on the site. What type of crime occurs in the area? What

crimes have occurred on the site? What were the causes of the crimes on site?

What crimes can be expected to occur on this property? How can those crimes

be prevented? In fact, a foreseeability survey should not have to wait until you

are planning a landscape project. You and your security consultant should have

researched foreseeability in advance as part of your litigation avoidance


Next, determine the impact that various types of landscaping will have on the

security of your facility. Will there be a positive or negative impact if you provide a

wall or visual barrier? How will lighting affect the building's security and mission?

Ascertain the role that the exterior area plays in your overall security program.

Does your exterior land serve as a visual no-man's land, calling attention to

intruders before they enter? Does it serve to slow them down as they leave,

making it impossible for them to carry away materials or property? Are you

already using your exterior as a tool in your protection program, or are you not

providing adequate security at this time?

To understand the role of landscaping in security, it is useful to understand

exactly what tools you have at your disposal. Fences, walls, water barriers,

walkways, plants, living barriers, lighting, and other elements all impact security

in some way. While some provide real security, others provide only psychological

security. For example, anyone intent upon entering a museum after first crossing

its beautiful artistic garden, will not be physically deterred by the hedges and

walkways. But a good landscape design will preserve lines of sight between

patrolling police or museum guards and the intruder, making the movement

through the site risky. Meandering walkways slow down an intruder or escaping

thief. Yet anyone leaving the walkway taking the "short cut" off the site will be


A museum or city park can never employ razor ribbon in its landscape design.

Few facilities can. But living hedges can be a valuable tool. One museum,

situated in a major city park where annual festivals occur, often experienced tree

damage from visitors climbing the trees to gain a vantage point for rock concerts

and other events. It replaced its trees with those bearing long thorns. In

protecting a space, do not underestimate the role of what some believe to be

merely "psychological security." If anyone really wanted to climb that tree they

could have, but the creative security manager made them want to go elsewhere.

Don't underestimate the need for compromise in filling your role as consultant to

the landscape architect. There are certain stipulations that we all must live with.

Those of us in museum security positions are very much aware of the need to

compromise. Given our preference, most of us would opt for locking away our

paintings in vaults and showing only good copies. We would put bullet-resistant

glass in front of pictures on display and never allow the visiting public true access

to the works of art. Of course, the museum's mission depends upon showing and

teaching about the original and not a copy. Conservation limitations do not permit

moving originals to storage vaults each night or even placing alarms on many

objects. For similar reasons, we may not encase some objects in bullet resistant

glass. Imagine a bank placing a quarter billion dollars worth of its assets in one

room and allowing the public to come in and view it!

Those in other industries are just now learning that there are rules they must

follow as well. When it comes to the exteriors of their beautiful buildings, owners

often tie the hands of security directors who want to install improved security.

After all, we build these buildings as to enhance our corporate image and are

often willing to assume great additional risk in order to make the land surrounding

our company headquarters do what we want it to do. We want it to express a

positive image that razor ribbon and land mines somehow don't convey.

Your guidance will help the landscape architect understand the risk, and locate

tools to reduce or eliminate it. Where an architect may think that a wall will be a

security improvement, you may make him/her aware that a solid wall affording no

sight lines through it actual increases risk. You might suggest that the same

effect can be achieved by using a hedge or transparent fence. While the solid

wall may be more difficult to breach, the thick hedge will permit greater visual

security once the intruder makes the penetration. Together, you can find

solutions that might not be readily apparent.

Explain to the architect the degree of risk to your facility and the role that you

expect the landscape to play in improving your situation. Present your findings on

the foreseeability of crime and the liability and obligation that your company--and

the architect--have to provide protection. Express the philosophy that security

and safety of visitors must be a paramount concern, and that how safe and

secure visitors feel will determine, in part, the user satisfaction with the facility.

Examine the level of access that your facility needs or the level of access that it

cannot tolerate. For example, if it is important that you keep cars from close

proximity to your building perimeter to preclude the use of a car bomb, then a

parking lot or street access is unacceptable in the plan within a distance to be

determined by further study. If you need clear, quick access for firefighters or

equipment, walls may not be appropriate.

Crowd flow in your landscape plan, (and access/pedestrian control must be

considered.) If, during the day, your goal is to provide a park like setting for your

visitors, to move freely through the landscaped area on a series of trails or paths,

to sit and read on benches, or to observe various plants or settings, then you can

adopt a concept known as "graduated difficulty of access." Graduated difficulty of

access involves using different trails or design elements which make access to

various areas more or less difficult than access to other areas. Each level of

access involves a greater degree of difficulty. By using this concept,

straightforward access can be eliminated by gates or other barriers at night, while

providing the full access to all levels by day. At night, the site becomes the no man's

land that slows intrusion and escape and makes an intruder visible.

Heavily landscaped areas using graduated difficulty of access concepts are

conducive to the use of electronic security, components of which can be hidden

among trails or landscape plantings. Your job is to make the architect aware of

your ideas, and his/ her job is to integrate security with landscape elements. Your

job also is to establish rules for use of the space after it is determined so that

they can be facilitated by the design. For example, if roadways or walkways

through the space are to be closed at night, design gates and a means of

securing the space at the time the space is initially designed.

What are the most common landscape elements available to us? We discussed

them briefly above.

Lighting is an important part of any landscape plan and an essential element of

security. With lighting, as with some other elements of security landscaping, care

must be taken to meet or exceed any standard or recommended practice which

might prevail in your industry or in general. There is no one master book of

security standards. Standards are being developed on a case-by-case basis and

in some cases, de facto standards exist in the form of recommended practices.

Also to be considered is the various case law affecting the need for security

lighting on a specific landscape. If, for example, you include parking in your plan,

much case law exists on the topic, and numerous texts can be used to determine

the basic requirements. Your locality may even have building codes that must be

complied with.

Lighting must be provided and scaled for all users of the space. Different lighting

is required for pedestrians, building protection, vehicles, bicycles, etc. Thought

must be given to providing backlighting or front lighting. Exterior spaces should

have a well defined sense of background. Background spaces should be

illuminated unobtrusively, possibly from walkways, providing an ability to

silhouette intruders. Foreground spaces should be lit by local lighting using

maximum focus, minimum distractions, and no glare. It is at the foreground

objects, such as benches, structures and sculptures, that people will congregate.

Light must be uniformly distributed and properly diffused, minimizing shadows.

Where changes in grade occur, it is useful to have horizontal illumination along

the ground plane.

In any case, the case law "standards" adopted for similar spaces with similar

risks, such as lighting standards for parking lots, should be met or exceeded. The

good practices in lighting, i.e. directing light away from the observing security

forces, maintaining overlapping cones of light, and keeping light "even" with few

contrasts, should be observed. *The Parking Lot and Garage Security

Handbook* by Norman Bottom provides considerable background as do the

"Security Law Newsletter" and the various Rusting Publication newsletters. While

your situation may differ, the publications provide excellent resource material to

help you determine the level of lighting and physical security that may be


In determining light levels, be sure that lighting is adequate for CCTV, if required,

and that plantings do not create high contrasts that make CCTV use difficult.

Note that many landscape architecture texts and reference books contain

suggested light levels. For example, one text uses the figure 0.6 foot candles of

light as adequate on bicycle paths that cut through parks. While this may be

sufficient for safety from collision, YOU, not the architect, should decide the light

level that is adequate for personal protection or for viewing intruders as they

approach your building.

When planning landscape lighting, ascertain whether the landscape lighting will

double as security lights or whether separate lighting will be provided for security

purposes. This will become particularly relevant if, at some time, you need to

reduce light levels. Without separate security capability, you may find that an

energy conscious management has eliminated all lighting in an economy move.

Color plays an important role in landscape as well. It is particularly useful in

aiding surveillance at a site using high resolution color CCTV. Incandescent

lights have superior color rendition and a warm white appearance. Short lamp life

may require greater maintenance and can reduce security if burned out lamps

are not replaced immediately. They also have the lowest efficiency. If high

pressure sodium, metal halide, mercury vapor, or low pressure sodium lights are

used, discuss the effects these light sources will have on surveillance equipment

and night color differentiation with your consultant.

Where changes in grade occur, it is useful to have horizontal illumination along

the ground plane. This serves to outline the intruder against the background.

Topography and grading can play a critical role in landscape security. The trend

in museum sculpture gardens and many corporate plazas is the placement of

sculpture below grade. Both the Hirshhorn Museum and the Baltimore Museum

of Art have had to take the expensive measure of adding a 24 hour guard in the

garden area because it is impossible to see the area below-grade from the

building. Not only are the works of art in an outdoor below grade sculpture court

at risk without added protection, but also visitors cannot be seen by building

guards. Fortunately, both of these gardens are not in areas with high crime or the

issue of foreseeability would be involved as well.

Topography can help make walls higher. How, you say? Let's say you have a

sculpture garden and the architect insists that the wall not be higher than six feet.

A six foot wall is almost ineffective against a determined intruder but you can

make it seem higher to the intruder without making it appear higher to the person

driving past the site by creating a swale between the wall and the sidewalk. To

climb the wall the intruder has to walk into the much lower swale and this may

add as much as two feet to his climb to get over the wall.

Topography and grading can benefit security if properly installed or controlled.

For example, one engineering firm offers topographic analysis to determine how

the land slope will serve to deflect bomb blasts, and how the deflected blast will

affect the specific structure. Slope also can be used as a backdrop to enhance

lighting and view of movement, if properly placed behind the moving target and

opposite the observer.

Walkways not only define, psychologically, where visitors may be, but they

facilitate crowd flow and circulation as well. When pedestrian movement is

perceived as purely functional and the goal is to move people expeditiously,

walkways can differ from those intended to be recreational or aesthetic. When

planning pedestrian walkways, great thought should be given to spatial

relationships with other elements. Can someone hide behind a bush or a

structure and reach a passerby? Does the hiding place provide sufficient cover to

allow an attack to occur undiscovered?

The appeal of watching other people is a common reason for the popularity of

landscaped environments such as parks and grounds. Security personnel

planning such spaces should use this fact in developing walkway systems that

allow the security of other people without giving up the illusion of seclusion.

Added security can be achieved by providing visitors with ever-present signage

or visual cues that allows them to know a route of escape.

Walls and fences can be a useful tool to security in a landscape design. Again,

lacking personal knowledge of security equipment and principles, architects need

our advice in deciding wall composition and design. Make them aware that

crossbars on an otherwise impossible-to-climb iron fence can turn the fence from

a barrier into a ladder. A high thick hedge that provides a reasonably good barrier

cannot accommodate an electronic fence protection system requiring a rigid


What is the purpose of the fence? Is it privacy, safety, security, visual barrier,

boundary definition, circulation control, environmental modification (hiding

nuisances), or aesthetics? Will traffic control structures or barriers be used? If so,

are they strong enough to really restrict vehicles? Much litigation has occurred

pertaining to claims by hardware manufacturers that their products can stop

vehicles when, in fact, they only discourage vehicles also.

Ask yourself--What structures will be on the site? How will they affect security?

Will they produce a hazard to visitors? Will they affect security of the main

building? Will water be part of the landscape? Will it be used for aesthetics or as

a security barrier? One major facility uses water as both an architectural feature

and as a security barrier. It is impossible to approach the building exterior on two

sides without a boat--except when the lake is frozen! Special care should be

taken when bridges are provided for passage over ponds, as they provide

considerable challenge to the security forces. Will there be pools and fountains?

Will they be an attractive nuisance? Can ponds play a role in fire fighting? Will

moving water in fountains affect exterior motion detection proposed? What

furniture will be provided on the site? How does it impact the security? Will

benches become an attractive nuisance for homeless persons or derelicts? Is

furniture located where it can be properly supervised on patrols? Can the bulk of

the furniture be observed by security? If furniture is placed in structures designed

to provide shade, does this detract from security? Will vehicle control barriers

obstruct views?

Will there be a need for utilities in the plan? Will the utilities affect the main

building? How will the utilities be protected from tampering or sabotage? Will the

landscaped area be above underground portions of the protected building? If so,

how will this affect security?

Will there be seasonal elements such as tents, canopies, awnings, umbrellas,

outdoor furniture, vending carts, planters, decorative banners, special signs, etc.

that might alter the security plan? Can these be used to hide bombs or weapons?

Will they obstruct views? What steps must be taken at the time of design to

accommodate these added risks and obstructions?

Plants and plantings are an inevitable part of a landscape design. The types of

plants that can be used in any given area will depend upon many considerations,

including length of growing season, high and low temperatures, water and

rainfall, soil, etc. While it is not possible to recommend a large variety of plants

that can be used in all environments, there are some popular plants that can be

used in many parts of the U.S. to assist security. Darrell Willson, a CPP, former

Executive Director of Protection Services for the Art Institute of Chicago, and a

former landscape professional, offers the following suggestions.

Hicks yews are the most versatile evergreen plant. The density of the plant will

generally disallow intruders and can be planted tightly enough to prevent

someone from hiding among the bushes. The Red Barberry is also a versatile

plant with thorny branches and deep red leaf color, making it an ideal plant for

hedging where a physical and psychological barrier is needed.

Willson also recommends the Washington Hawthorne, a thorny ornamental tree

which reaches approximately 25 feet in height. The thorns provide no real

hazard, but make hiding in the tree unlikely. Another ornamental, the burning

bush, makes a good hedge material and foundation plant. Its tightly woven

branch structure is a plus, and its thorns preclude anyone from hiding among the


Pyracantha is a thorny plant that also serves as a foundation plant where lots of

room is given for growth. This plant can be shaped to create a good wall cover

and is ideal for use against perimeter walls, where it is not desirable to allow

intruders to make a close approach.

In tropical climates, there are other selections that can be made due to thickness

and leaf texture. Palm trees provide an excellent alternative. With their foliage at

the top of the tree, they provide little room for hiding at the ground level.

Foundation plantings should be established with low growing, tightly branched

material to reduce the advantage trees provide for intruders. Perimeter plantings

should be thorny so that the opportunity for hiding would be reduced. The

landscape plan should not include large bushy plants. Hedges are important to

prevent intrusion, however, they must be chosen carefully or they can become a

place to hide.

If it is desirable to allow people to walk freely through the landscaped area but

prevent them from laying or sitting on the grass, grass can be substituted with

gravel, sand, or ground-cover plantings. Great thought should be given to the

mature size of all trees planted. At full size, will they provide easy climbing

access to building roof systems or windows?

Landscape architects often use dense plantings and walls to reduce sound

distractions from traffic or outer sources. While it is desirable to make a quiet

setting for users of the landscaped area, take care not to allow sound proofing to

reduce your ability to conduct successful surveillance of the site. Sound control is

usually accomplished by dense vegetation, solid barriers, earth berms, and by

providing spaces, like the sculpture courts previously discussed, below grade.

Nearly every solution for sound control that the architect may propose will have a

negative impact on security.

What are the various steps in the landscape process? Your architect will begin by

assessing the site and preparing a program. As discussed earlier, you must get

your thoughts included in the earliest steps, or you may miss the opportunity to

contribute to the process. Next, the landscape architect will prepare a design

which will, at some point, include construction documents. Construction

documents will include drawings and specifications, which will be used for

bidding the project to contractors. Drawings will be drawn to scale so that

contractors can assess the spatial relationships of proposed objects to each

other and to existing known points. Specifications include detailed descriptions

of general conditions, special provisions, materials, quantities, and information on

installation. You must review these documents very carefully and use them to

include any aspects of your concern that have not been included.

If a general architectural or engineering firm is not involved in the process and

you find it necessary to include security lighting, CCTV, or alarm components in

the plan, it may be necessary to have a security design professional, such as a

capable security consulting firm, prepare drawings and specifications for the

security system components. Do not delay in bringing in security expertise.

Have your landscape architect include elevation drawings in the drawings that

he/she provides. Elevations are drawings showing what the setting will look like if

viewed from various directions. Elevations allow you to see the height of various

trees or elements as they will appear, and in scale. Structures, bridges or other

barriers do not change in size, but plantings do. Be certain to discuss in detail the

affect that plantings will have when full grown. What maintenance will be required

to keep plantings under control to the extent that they will not obstruct sight lines,

lighting, and CCTV or alarm equipment? Will the owner make the necessary

commitment to maintain the plantings so that they will not grow to problem

heights or width? Also to be considered is the affect that full-grown plantings will

have from above should you need to observe from the air or from upper floors.

Remember that what you see on the plans and what you will get depends on

many variables and can change up to the last minute. Can the buyer obtain a

sufficient quantity of matched trees in a specific size or will he change the size or

even species that he buys?

Once the landscape plan is accepted and construction begins, it will be

necessary to make plans for adequate security during this process.

Another consideration is the affect that the surrounding landscape will have on

the protected building. If the area is prone to range fires, as is the case when the

Santa Ana winds and dry conditions threaten the hills surrounding Los Angeles, it

might be preferable to look at the added risk your plantings might cause. In

addition to fire, other natural disasters might be foreseeable. Do you live in a

flood area? Are you prone to earthquakes? Do you have electrical storms? Will

that new flagpole attract lightning? Will that observation tower collapse? Will the

snows drift as a result of your landscape? Should those dry plants be replaced by

rock gardens to control fires?

When planning landscape designs, employ modern, electronic security devices

as part of your integrated package, which also includes lighting, CCTV, guards,

walls and physical barriers, etc. On-screen motion detection can be an

appropriate tool in detection of activity in the space as can pulsed infrared

beams, which crisscross walkways and planted areas. Hidden vehicle detectors

also should be considered as appropriate.

A final concern in landscape security comes when your hands are even more tied

by the fact that your landscape involves restoration of a site to its original historic

situation. You cannot control the use of elements as carefully as you otherwise


Historic landscapes are the landscapes of the past. They do not normally include

wilderness or natural landscapes and usually focus on the cultural landscape and

the human contribution in the existing space. They reflect the unique tastes,

technologies, and needs of the period portrayed. Usually the landscape included

gardens, plantings, structures, furniture, etc. The degree of control that you have

on the design elements will depend upon how historically accurate your

restoration of the landscape must be.

When the security director finds that he/she cannot control the landscape by

changing topography, plantings, walkways, lighting, etc., plans to improve

security by improving the landscape must be abandoned. The security director

should concentrate on providing "old fashioned" protection afforded by guards

and conventional means. It must be recognized that the intrusion of modern

security equipment probably will be frowned upon by the architect, and every

effort will have to be expended in designing in concealed cameras, alarms, etc.

Thus it would be wise to obtain the assistance of a security consultant,

specializing in historic restorations, at the earliest phase in this process.

In recent years there has been a trend toward building "green" buildings and for

pursuing green certification. Often, green building design involves extensive use

of trees to provide shade to the building thus reducing energy use. The security

manager must be alert to overhanging branches or trees that can be climbed

giving access to upper portions of the building. A balance must be found that

includes sustainability, reduced carbon footprint and security.

Much can be done by the security professional to improve security by

manipulating the landscape plan at the protected site. Security landscaping is

simply a matter of manipulating the elements of landscape architecture in a

positive way and using every opportunity available to you. To be successful, you

must be an active participant in the development of the plan. You must consider

current and future crime trends in determining appropriate levels of security, and

you must evaluate the criticality of the protection mission at the main building.

The responsibility for using landscape architecture as a tool of physical and

psychological security rests with the modern security professional.

Copyright 2011 by Steve Keller. All Rights Reserved. You may reproduce this for your in house

use. If you do, please retain the author's byline and this copyright notice.

The author is a former museum security director and currently is a security consultant.

“Botanical Gardens Security

Risk Checklist”

by Robert Carotenuto


Using Landscaping to Improve Security

Originally published in “Security Management”