Mixed Deck — All CLARB Topics Flashcards

During the construction of a segmental retaining wall, a non-woven geotextile filter fabric is specified for placement behind the drainage aggregate. What is the main function of this fabric?

Answer: To prevent the migration of fine soil particles into the drainage aggregate.

The primary function of a non-woven geotextile in this application is filtration and separation. It allows water to pass through into the drainage aggregate but prevents fine soil particles from the retained earth from migrating and clogging the aggregate, which would compromise the drainage system's effectiveness and increase hydrostatic pressure.

Hydric soils serve as a primary indicator for identifying which regulated landscape feature during site analysis?

Answer: Jurisdictional wetlands

Hydric soils formed under prolonged waterlogged conditions exhibit mottling, gleying, and low chroma colors that indicate wetland conditions, and are one of the three required criteria for jurisdictional wetland delineation.

Under the Clean Water Act Section 404, what activity on a CLARB project site would require a permit from the US Army Corps of Engineers?

Answer: Discharge of dredged or fill material into waters of the United States, including wetlands

Section 404 requires a USACE permit for any discharge of fill material into jurisdictional waters of the US, including wetlands, streams, and other water bodies.

What is the primary significance of the Certificate of Substantial Completion?

Answer: It marks the date when the warranty period for the contractor's work begins.

Substantial Completion is the stage at which the work is sufficiently complete in accordance with the contract documents so that the owner can occupy or utilize the work for its intended use. This is a critical milestone because it typically marks the start of the contractor's warranty period and the transfer of responsibility for security, maintenance, and insurance from the contractor to the owner. The punch list of minor corrective items is usually generated at this stage, and final completion occurs after these items are addressed.

The angle of repose is a critical soil engineering property that most directly influences which landscape design consideration?

Answer: Slope stability and cut/fill grading design

The angle of repose defines the steepest angle at which loose soil remains stable; it directly dictates maximum allowable slope gradients for cut and fill sections.

Which of the following is a common cause for a contractor's bid to be deemed non-responsive and rejected during a formal bidding process?

Answer: The bid form was submitted after the specified deadline.

Bidding documents clearly state the deadline for bid submission. Failure to submit the bid by the specified date and time is a material irregularity and a primary reason for a bid to be rejected as non-responsive, regardless of its price or other merits.

What plant characteristic is described by the term 'apical dominance'?

Answer: The suppression of lateral bud growth by hormones from the terminal bud

Apical dominance is the hormonal suppression of lateral bud growth by auxins produced in the terminal (apical) bud, causing the plant to prioritize upward growth.

What is the primary environmental benefit of specifying permeable pavement in a landscape design?

Answer: Allowing stormwater to infiltrate into the ground, reducing runoff and recharging groundwater

Permeable pavement allows rainwater to pass through the surface into a stone reservoir base, reducing runoff volume, improving water quality through filtration, and recharging groundwater.

What is the primary purpose of the USDA Plant Hardiness Zone Map in landscape architectural practice?

Answer: To determine which plants will survive winter temperatures in a given region

The USDA Plant Hardiness Zone Map divides North America into zones based on average annual minimum winter temperatures to guide plant selection.

What soil test result would most commonly prompt a landscape architect to recommend sulfur amendments prior to planting acid-loving species like azaleas?

Answer: Soil pH above 6.5, indicating alkaline conditions unsuitable for acid-loving plants

Azaleas and other ericaceous plants prefer pH 4.5–6.0, so elemental sulfur is added to lower soil pH when results show neutral to alkaline conditions.

What is the primary purpose of construction documentation in landscape architecture?

Answer: To communicate detailed design and construction requirements to the contractor

Construction documentation, including drawings and specifications, serves as the primary communication tool between the designer and the contractor. It provides all the necessary technical information, dimensions, materials, and methods required to accurately build the landscape design. This ensures the project is constructed according to the design intent and meets quality standards.

Which plant growth habit describes a plant that completes its entire life cycle in one growing season?

Answer: Annual

Annuals germinate, flower, set seed, and die within a single growing season, requiring replanting each year.

What is the purpose of a vegetated (green) roof in sustainable landscape design?

Answer: To reduce stormwater runoff, improve building insulation, and mitigate the urban heat island effect

Green roofs reduce stormwater runoff volume and peak flow, improve building energy efficiency through added insulation, and help cool the urban environment by mitigating the heat island effect.

Which type of drawing illustrates surface elevations and drainage patterns?

Answer: Grading and drainage plan

A grading and drainage plan uses contour lines and spot elevations to illustrate the proposed changes to the land's surface elevation. It clearly shows how water will flow across the site, indicating swales, slopes, and collection points. This plan is critical for ensuring proper site drainage, preventing erosion, and creating stable, usable outdoor spaces.

What document outlines the scope of work, project details, and responsibilities during construction?

Answer: Construction contract

A construction contract is a legally binding document that outlines the complete scope of work, project details, and responsibilities of all parties involved in a construction project. It serves as the foundational agreement, specifying timelines, costs, materials, and quality standards, ensuring clarity and accountability throughout the build.

What does the term 'impervious surface coverage ratio' measure on a development site?

Answer: The percentage of a site covered by materials that do not allow water infiltration into the soil

Impervious surface coverage ratio expresses the proportion of a site covered by roofs, pavement, and other surfaces that prevent stormwater infiltration, which many municipalities regulate.

What term describes the maximum amount of water a soil can hold after excess gravitational water has drained away?

Answer: Field capacity

Field capacity is the soil moisture content remaining after gravitational drainage has ceased, typically reached 24-48 hours after saturation.

A planting plan calls for 'native species only.' Which of the following best describes a native plant in the US context?

Answer: A species that occurred naturally in a region prior to European colonization

Native plants are those that evolved and existed in a specific region before European settlement, forming ecological relationships with local wildlife and soil organisms.

Which soil horizon is commonly referred to as 'topsoil' and contains the highest concentration of organic matter?

Answer: A horizon

The A horizon (topsoil) is the uppermost mineral soil layer and contains the greatest accumulation of organic matter and biological activity.

What does the term 'caliper' refer to when specifying nursery stock trees on a CLARB planting plan?

Answer: The diameter of the trunk measured 6 inches above grade for trees up to 4-inch caliper

Caliper is the standard measurement of trunk diameter taken 6 inches above ground level for nursery stock up to and including 4-inch caliper, per ANSI Z60.1 standards.