CSLB Landscaping (C-27) Trade — All Questions
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400 questions
Aggregate base under hardscape is best compacted in what manner?
- a.Only after the pavers have been placed
- b.In thin lifts, each compacted before the next✓
- c.By soaking it thoroughly with water only
- d.In one thick lift with no compaction at all
Base material should be placed and compacted in thin lifts, commonly around 3 to 4 inches, so the compactor can achieve full density throughout. Compacting one thick lift leaves the lower portion loose, causing later settlement. Layered compaction produces a stable, uniform base.
A segmental retaining wall over a certain height typically requires what to prevent failure?
- a.Engineered design, drainage, and geogrid✓
- b.No drainage of any kind behind the wall
- c.Only a decorative facing on the wall front
- d.A smooth clay backfill packed tight
Taller retaining walls carry large lateral soil loads and usually require engineered design, gravel backfill with a drain to relieve water pressure, and geogrid soil reinforcement. Without drainage, water pressure builds behind the wall and pushes it over. Many jurisdictions require permits and engineering above a set height, commonly 3 to 4 feet.
Weep holes or a drainage system behind a retaining wall serve what purpose?
- a.To relieve hydrostatic pressure behind the wall✓
- b.To hold more water in the backfill zone
- c.To increase the soil pressure on the wall
- d.To add decorative accents to the wall face
Weep holes and gravel drains allow water that collects behind a wall to drain out, relieving hydrostatic pressure that would otherwise push the wall over. Saturated soil greatly increases the load on a wall. Proper drainage is one of the most important factors in wall longevity.
A slope is described as 4:1. What does this mean?
- a.A 40 percent grade down the bank
- b.A vertical cliff with no run at all
- c.4 feet of run for every 1 foot of rise✓
- d.4 feet of rise for each 1 foot of run
A 4:1 slope means 4 units of horizontal distance for every 1 unit of vertical change, a gentle 25 percent grade. The first number is run and the second is rise in this common landscaping convention. Flatter ratios like 4:1 are more stable and easier to mow than steep ones like 2:1.
Managing stormwater runoff on a site with a bioswale accomplishes what?
- a.Slows runoff, filters pollutants, and promotes infiltration✓
- b.Prevents any water from infiltrating
- c.Raises the water table intentionally
- d.Concentrates runoff into a single fast channel
A bioswale is a shallow, vegetated channel that slows stormwater, filters out sediment and pollutants, and encourages water to soak into the ground. This reduces peak runoff and improves water quality leaving the site. Such low-impact designs are increasingly required for stormwater management.
A concrete slab for a patio typically includes control joints. What is their function?
- a.Planned weak points so cracks follow the joint✓
- b.Eliminating the need for a compacted stone base
- c.Increasing the water content of the slab
- d.Adding decorative color to the surface
Control joints are grooved or cut lines that create a deliberate weak plane, so as concrete shrinks and cracks, the cracks form neatly along the joint rather than randomly across the slab. They are usually spaced in feet roughly equal to two to three times the slab thickness in inches. They control, not eliminate, cracking.
Edge restraints installed around a paver patio serve what main purpose?
- a.To replace the compacted gravel base layer
- b.To keep pavers from spreading outward over time✓
- c.To change the color of the paver surface
- d.To provide seating around the patio edge
Edge restraints lock the perimeter pavers in place so the field of pavers cannot creep or spread apart under traffic. Without them, edges migrate and joints open up, leading to failure. They are a small but essential part of a durable paver installation.
A paved surface should be sloped for drainage at about what minimum cross slope?
- a.0 percent (dead level)
- b.10 to 15 percent
- c.Sloped toward the house
- d.About 1 to 2 percent✓
Paved surfaces such as patios and walkways are typically sloped about 1 to 2 percent, roughly 1/8 to 1/4 inch per foot, to shed water without being noticeably tilted. A dead-level surface ponds water, while too steep a slope is uncomfortable and unsafe. Water should always be directed away from structures.
A catch basin connected to underground drain pipe is used to do what?
- a.Collect surface water and pipe it away✓
- b.Store irrigation water for later reuse
- c.Support the base of a retaining wall
- d.Filter drinking water before use
A catch basin is a boxed inlet set at a low point that collects surface runoff and channels it into buried drain pipe leading to a safe discharge. A grate on top keeps out leaves and debris. It is a key part of a yard drainage system that prevents ponding.
When laying out a site from a plan, a builder's level or laser level is used primarily to establish what?
- a.Plant spacing across the planting beds
- b.Consistent elevations and grades✓
- c.Soil pH in the planting areas
- d.Water pressure at the meter
A builder's level, transit, or rotary laser establishes accurate reference elevations so grades, slopes, and drainage can be set consistently across a site. This ensures the finished landscape drains correctly and matches the plan. Accurate layout prevents costly grading errors.
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Compaction of subgrade soil before hardscape is measured against what standard reference?
- a.A percentage of maximum dry density✓
- b.The number of compactor passes only
- c.The measured pH of the subgrade soil
- d.The color of the compacted soil
Compaction is specified as a percentage of a soil's maximum dry density determined by a laboratory Proctor test, commonly 90 to 95 percent for hardscape subgrade. Field testing verifies the soil reaches the required density. Adequate compaction prevents future settlement under pavement.
On expansive clay soils, hardscape and foundations are at risk because the soil does what?
- a.Stays perfectly stable in all conditions
- b.Turns to sand over time
- c.Swells when wet and shrinks when dry, causing movement✓
- d.Never holds water
Expansive clays contain minerals that absorb water and swell, then shrink as they dry, producing repeated ground movement that cracks slabs and walls. Managing moisture and using proper base and drainage details reduces this movement. Severe cases may need engineered foundations.
A dry-stack (mortarless) segmental block wall relies on what for stability?
- a.Steel beams set behind the block face
- b.A mortared concrete cap along the top
- c.Mortar placed between every block course
- d.Interlock, batter, and gravel backfill✓
Mortarless segmental walls gain stability from the interlocking block design, a slight backward lean (batter or setback), free-draining gravel backfill, and geogrid reinforcement layers in taller walls. There is no mortar, so drainage and reinforcement carry the loads. Proper base preparation is also critical.
Directing a downspout's discharge onto a splash block or into a pipe that carries it away from the house prevents what?
- a.Better interlock between the patio pavers
- b.A higher soil pH near the foundation
- c.Faster plant growth beside the house
- d.Erosion and ponding at the foundation✓
Concentrated roof runoff from a downspout can erode soil and saturate the ground against a foundation, leading to settlement and moisture intrusion. A splash block or piped extension moves that water away from the structure. This is a basic but important part of site drainage design.
Permeable pavers differ from standard pavers because they do what?
- a.They require no base course at all
- b.They are decorative only, not structural
- c.They block all water from passing through them
- d.They let stormwater soak through the joints✓
Permeable pavers are set with open, aggregate-filled joints over an open-graded stone base so rainwater infiltrates rather than running off. This reduces runoff volume and helps recharge groundwater, supporting stormwater regulations. They require a specially designed base to store and drain the water.
On a steep planted slope, which practice BEST controls erosion during establishment?
- a.Leaving the slope soil bare and exposed
- b.Frequent heavy flood irrigation
- c.Smooth compaction with no plants
- d.Blankets, mulch, and quick groundcover✓
Covering a slope with erosion-control blankets or netting, mulch, and fast-establishing groundcover protects the soil surface from rain impact and runoff until roots hold it. Bare or heavily flooded slopes erode and rill quickly. Vegetation and surface protection together stabilize the slope.
A retaining wall's footing or leveling pad should be placed on what?
- a.A layer of dry leaves and loose topsoil
- b.Compacted, level base at the proper depth✓
- c.Loose topsoil raked out smooth
- d.A single row of bricks laid flat
The base or leveling pad of a retaining wall must rest on compacted, level base material set at the correct depth so the wall does not settle or lean. A poor base is a leading cause of wall failure. Getting the first course level and solid is essential for the whole wall.
How many cubic yards of soil are needed to cover a 30 ft by 18 ft bed 6 inches deep?
- a.About 5 cubic yards
- b.About 2 cubic yards
- c.About 10 cubic yards✓
- d.About 20 cubic yards
Volume in cubic yards equals length times width times depth in feet divided by 27. Here 30 x 18 x 0.5 equals 270 cubic feet, divided by 27 equals 10 cubic yards. Six inches must be converted to 0.5 feet before calculating.
The formula for calculating cubic yards of bulk material for a rectangular area is which of the following?
- a.Length plus Width plus Depth
- b.Length x Width x Depth divided by 12
- c.Length x Width divided by 27
- d.Length x Width x Depth (all in feet) divided by 27✓
Because a cubic yard contains 27 cubic feet (3 x 3 x 3), you compute the volume in cubic feet and divide by 27 to get cubic yards. All three dimensions must be in feet, so inches of depth are converted first. This formula applies to soil, mulch, gravel, and concrete.
A mulch supplier sells by the cubic yard. To mulch 900 square feet at 3 inches deep, how many cubic yards are required?
- a.About 2.8 cubic yards
- b.About 5 cubic yards
- c.About 27 cubic yards
- d.About 8.3 cubic yards✓
Convert 3 inches to 0.25 feet, then 900 x 0.25 equals 225 cubic feet, divided by 27 equals about 8.3 cubic yards. Always convert the depth to feet before dividing by 27. Ordering the right amount avoids extra delivery trips.
To find the area of a circular planting bed with a 20-foot diameter, which calculation is correct?
- a.3.14 x 20 (about 63 square feet)
- b.2 x 3.14 x 10 (about 63 square feet)
- c.20 x 20 (about 400 square feet)
- d.3.14 x 10 x 10 (about 314 square feet)✓
Circle area equals pi times the radius squared, and the radius is half the diameter, so 10 feet. Thus 3.14 x 10 x 10 equals about 314 square feet. Using diameter instead of radius is a common estimating error.
A landscape plan uses a scale of 1 inch = 10 feet. A bed measures 4 inches long on the plan. What is its actual length?
- a.40 feet✓
- b.14 feet
- c.400 feet
- d.4 feet
At a scale of 1 inch equals 10 feet, you multiply the drawing measurement by 10 to get the real dimension. So 4 inches times 10 feet equals 40 feet. Reading scale correctly is essential for accurate takeoffs from plans.
A patio is 12 ft by 15 ft and will be poured 4 inches thick. How many cubic yards of concrete are needed (before waste)?
- a.About 0.7 cubic yards
- b.About 15 cubic yards
- c.About 2.2 cubic yards✓
- d.About 6.7 cubic yards
Convert 4 inches to 0.333 feet, then 12 x 15 x 0.333 equals about 60 cubic feet, divided by 27 equals about 2.2 cubic yards. Contractors often add roughly 5 to 10 percent for waste and spillage. Ordering slightly extra avoids a short pour.
When estimating a job, which cost category covers wages, taxes, and workers' compensation for crew hours?
- a.Permit fees
- b.Labor cost✓
- c.Material cost
- d.Equipment rental
Labor cost includes crew wages plus payroll burdens such as payroll taxes and workers' compensation insurance. Estimators calculate labor from the hours a task takes multiplied by a fully burdened labor rate. Underestimating labor is a common cause of unprofitable jobs.
How many square feet are in a rectangular lawn that is 45 feet by 60 feet?
- a.270 square feet
- b.2,700 square feet✓
- c.1,050 square feet
- d.105 square feet
Area of a rectangle is length times width, so 45 times 60 equals 2,700 square feet. This area figure is then used to calculate seed, sod, fertilizer, or irrigation coverage. Getting the area right is the foundation of most landscape takeoffs.
A fertilizer is applied at 4 pounds per 1,000 square feet. How much is needed for 5,000 square feet?
- a.2 pounds
- b.4 pounds
- c.20 pounds✓
- d.40 pounds
Divide the total area by 1,000 to get 5 units, then multiply by the 4-pound rate to get 20 pounds. Application rates per 1,000 square feet are standard in turf care. Measuring area accurately prevents over-application and fertilizer burn.
Before starting many hardscape or grading projects, a contractor typically must obtain what from the local jurisdiction?
- a.A seed certificate
- b.A fertilizer license only
- c.A paint color approval
- d.The required building or grading permit✓
Grading, retaining walls over a set height, and other hardscape work usually require a permit and inspections from the local building or public works department. Permit review checks drainage, setbacks, and structural safety. Skipping required permits can lead to fines and forced removal.
A sod order covers 2,700 square feet. Sod is sold in pieces covering 10 square feet each. Roughly how many pieces are needed, ignoring waste?
- a.270 pieces✓
- b.2,700 pieces
- c.135 pieces
- d.27 pieces
Divide the total area by the coverage per piece: 2,700 divided by 10 equals 270 pieces. Installers usually add about 5 percent extra for cuts and irregular edges. Ordering by coverage prevents running short mid-installation.
On a landscape plan, a legend or symbol schedule is used to do what?
- a.It shows the property tax value
- b.It provides the full soil test results
- c.It lists the owner's phone number
- d.It identifies each symbol and plant✓
The legend, sometimes called a plant schedule or symbol key, explains what each graphic symbol and abbreviation on the plan means, including plant species, quantities, and sizes. Reading it correctly is essential to an accurate takeoff and installation. It ties the drawing to real materials.
A contractor marks up material and labor to cover office costs, insurance, and profit. This markup is commonly called what?
- a.A material discount
- b.Sales tax
- c.A permit fee
- d.Overhead and profit✓
Overhead and profit is the markup added on top of direct job costs to cover indirect business expenses like office, insurance, and vehicles, plus the profit the company earns. Without adequate overhead and profit, a business cannot sustain itself. It is a standard part of professional estimating.
Before any excavation or trenching in California, the law requires a contractor to do what?
- a.Only notify the adjacent property owners
- b.Wait 30 days before starting work
- c.Dig a test hole first without notice
- d.Contact DigAlert (811) to mark utilities✓
California Government Code section 4216 requires excavators to contact the regional one-call center, DigAlert (811), at least two working days before digging so utility owners can mark their buried lines. This prevents striking gas, electric, and other utilities. Failing to call can cause deadly accidents and legal liability.Gov Code §4216 (DigAlert)
Under Cal/OSHA, a trench generally must be protected by sloping, shoring, or shielding once it reaches what depth?
- a.5 feet, or less where a hazard exists✓
- b.20 feet or deeper in any soil type
- c.50 feet or deeper in any soil type
- d.2 inches or deeper in any loose backfill
Cal/OSHA requires cave-in protection such as sloping, benching, shoring, or a trench box for excavations 5 feet deep or greater, and even shallower trenches if a competent person identifies a hazard. Unprotected trenches can collapse and bury workers in seconds. A competent person must inspect trenches daily.Cal/OSHA Title 8
California's Heat Illness Prevention standard requires employers to provide which of the following to outdoor workers?
- a.Ice cream breaks during the shift
- b.Only drinking water on very hot days
- c.Nothing at all until a worker actually faints
- d.Shade, drinking water, rest breaks, training✓
Cal/OSHA's Heat Illness Prevention standard requires access to shade, plenty of cool drinking water, cool-down rest breaks, acclimatization, and training on recognizing heat illness. High-heat procedures kick in at certain temperatures. Landscapers work outdoors and are a key covered group.Cal/OSHA Title 8
When operating a walk-behind mower on a slope, the recommended practice is to do what?
- a.Mow only when the grass is wet
- b.Mow across the slope, side to side✓
- c.Mow straight up and down the slope
- d.Remove all guards before mowing
With a walk-behind mower you mow across the face of a slope so the machine cannot roll back over you and you keep better footing. The opposite applies to riding mowers, which are safer going up and down. Never remove safety guards, and keep hands and feet away from the deck.
In California, a person who applies restricted-use pesticides for hire generally must hold what?
- a.A county-issued food handler card
- b.No license or certificate of any kind
- c.A Qualified Applicator License (QAL/QAC)✓
- d.Only a valid California driver's license
California requires applicators of pesticides for hire to be properly licensed or certified, such as holding a Qualified Applicator License (QAL) or Qualified Applicator Certificate (QAC) depending on the work. These credentials show the person is trained in safe, legal pesticide use. Landscapers applying pesticides commercially must comply.
A Safety Data Sheet (SDS) for a landscape chemical provides what information?
- a.The pipe size to use for the supply line
- b.The plant's watering schedule
- c.Hazards, PPE, first aid, and storage✓
- d.The retail price of the product
A Safety Data Sheet lists a chemical's hazards, required personal protective equipment, first aid measures, safe handling and storage, and spill response. Employers must keep SDSs accessible to workers under the hazard communication standard. Workers should review the SDS before using any chemical.
When operating a gas-powered chipper/shredder, which practice is safest?
- a.Feed material with bare hands past the intake
- b.Reach into the feed chute while it runs
- c.Wear loose clothing and no eye protection
- d.Wear eye and hearing protection, hands clear✓
Chippers demand snug clothing, eye and hearing protection, and keeping hands well back from the feed opening, using a push stick or the branch itself to feed material. Never reach into the chute while the machine runs, as the feed mechanism can pull in a hand or arm instantly. Always shut down and lock out before clearing a jam.
When using a chainsaw or working near it, which PPE combination is appropriate?
- a.Only sandals and sunglasses on hot days
- b.Chaps, eye and hearing protection, gloves✓
- c.No protection is needed for short cuts
- d.A single glove and shorts in warm weather
Proper chainsaw PPE includes cut-resistant chaps, eye and hearing protection, sturdy gloves, and a hard hat when limbs could fall. This gear protects against kickback, flying debris, noise, and falling branches. Skipping PPE, even for short cuts, causes serious injuries.
Before servicing or clearing a jam in powered landscape equipment, the safest first step is what?
- a.Have a coworker hold the blade steady first
- b.Simply tilt the machine on its side
- c.Increase the throttle to clear it
- d.Shut off the engine and disconnect the plug✓
Powered equipment must be shut off and its energy source isolated, such as disconnecting the spark plug wire or applying lockout/tagout, before anyone clears a jam or services it. This prevents accidental startup that could amputate fingers or hands. It is a fundamental rule for mowers, trimmers, and chippers.
A contractor with employees in California generally must have which of the following?
- a.A written Injury and Illness Prevention Program✓
- b.A single first aid bandage kept in the work truck
- c.Nothing in writing is required at all
- d.Only a business card for the crew lead
Cal/OSHA requires nearly every California employer to establish and maintain a written Injury and Illness Prevention Program (IIPP) that identifies hazards and sets procedures to correct them. It must include training, inspections, and a way for employees to report hazards. It is a foundational Cal/OSHA safety requirement.Cal/OSHA Title 8
When mixing and applying pesticides, the label directions are legally significant because what?
- a.They can be ignored by licensed applicators
- b.They apply only to homeowners
- c.They are only suggestions
- d.The label is the law and must be followed exactly✓
Under pesticide regulations, the product label is a legal document, and using a pesticide in a manner inconsistent with its labeling is a violation. The label specifies rates, sites, PPE, and restrictions that must be followed exactly. This protects applicators, the public, and the environment.
Early signs of heat exhaustion in a worker include which of the following?
- a.Improved strength and steady energy
- b.Heavy sweating, weakness, dizziness, nausea✓
- c.Dry, comfortable skin and clear thinking
- d.No symptoms at all until collapse
Heat exhaustion commonly shows as heavy sweating, weakness, dizziness, nausea, and headache, and it can progress to life-threatening heat stroke if ignored. Affected workers should move to shade, cool down, and drink water. Recognizing these signs early is part of required heat illness training.
When lifting heavy bags of soil or stone, the correct technique is to do what?
- a.Bend the knees and keep the back straight✓
- b.Hold the load out away from the body
- c.Bend at the waist and twist to lift
- d.Lift with straight legs and rounded back
Safe lifting keeps the back straight, bends the knees, and uses the leg muscles to raise the load held close to the body, avoiding twisting. This reduces strain on the lower back, a leading source of landscaping injuries. Heavy or awkward loads should be split or team-lifted.
When working near overhead power lines with tall equipment or ladders, workers must do what?
- a.Keep clearance and treat lines as live✓
- b.Lean the ladder against the power line
- c.Ignore the lines if they look old and worn
- d.Touch the line briefly to test it
All overhead lines should be treated as energized, and workers must keep required minimum clearances with ladders, poles, and equipment such as loaders and tree-trimming gear. Contact or arcing can be fatal. When work must occur close to lines, the utility should be contacted to de-energize or cover them.
Pesticide containers, after being emptied, should be handled how?
- a.Left open in the yard for later reuse
- b.Triple-rinsed and disposed of by label✓
- c.Buried anywhere on the job site after use
- d.Reused to carry drinking water for crews
Empty pesticide containers should be triple-rinsed, with rinse water added to the spray tank, then disposed of per the label and local regulations. They must never be reused for food, water, or other purposes. Proper disposal prevents contamination and accidental poisoning.
A 'competent person' on a trenching job is someone who can do what?
- a.Sell the customer additional trench work
- b.Only operate the excavator safely
- c.Sign the contract for the job
- d.Spot hazards and correct them promptly✓
Cal/OSHA defines a competent person as one capable of identifying existing and predictable hazards and who is authorized to take prompt corrective measures to eliminate them. On trenching jobs this person inspects the excavation, soil, and protective systems daily. Their authority to stop unsafe work is essential.Cal/OSHA Title 8
When operating a trencher, the operator should do what to stay safe?
- a.Keep bystanders clear and watch for utilities✓
- b.Dig first, then call DigAlert afterward
- c.Wear loose jewelry and listen to headphones
- d.Let bystanders stand next to the digging chain
Trencher safety means keeping bystanders back, working only after utilities are located and marked, and keeping hands, feet, and clothing away from the moving digging chain. Loose items can be caught by the chain. Utility location must happen before, not after, digging.
When climbing to prune a tree, a professional arborist relies mainly on what for fall protection?
- a.No protection when pruning low limbs
- b.Holding branches with one hand only
- c.A rope, saddle, and secure tie-in point✓
- d.Standing on the top rung of a stepladder
Professional tree climbers use a rope-and-saddle climbing system tied into a sound anchor point to protect against falls while working aloft. Standing on the top of a ladder or relying on hand grip is unsafe. Proper tie-in and inspected gear are essential for tree work.
Appropriate PPE for a worker applying a liquid herbicide typically includes which of the following?
- a.Chemical-resistant gloves and eye protection✓
- b.Only sunglasses and a light cotton shirt
- c.No gloves, so you can feel the sprayer
- d.Shorts and open sandals in warm weather only
Applying liquid pesticides calls for chemical-resistant gloves, eye protection, long sleeves and pants, closed shoes, and whatever additional protection the label requires, which can include a respirator. The label specifies the minimum PPE for that product. Skin and eye contact with concentrates can cause serious harm.
Backing up a truck and trailer or operating equipment in a crew area is made safer by which practice?
- a.A trained spotter and a working backup alarm✓
- b.Turning off all the mirrors first
- c.Letting anyone stand behind the vehicle
- d.Backing quickly with no one watching
A trained spotter, functioning backup alarm, and careful blind-spot checks greatly reduce the risk of striking a worker or object while backing. Landscape crews often work in tight spaces with equipment moving nearby. Clear communication and awareness prevent serious struck-by incidents.