Landscape Contracting Trade Knowledge and Construction Practices
Domain 2 - Landscape contracting trade knowledge and construction practices
This domain tests whether you can build a landscape that survives a Nevada summer: soil and drainage, irrigation design, plant selection and installation, hardscape, and water rules.
Soils, grading, drainage
- Nevada soils are often alkaline, high in salts, low in organic matter, and layered with caliche. Test before designing; amend with compost, not blanket gypsum (gypsum targets sodic soils specifically).
- Grade to drain: roughly 2% away from structures, swales where sheet flow would cross a walk, no ponding against walls or footings.
- Plant into a loosened pit two to three times the root ball width; never dig a glazed 'flowerpot' hole in clay.
Irrigation
- Design by hydrozone: turf, shrubs, and trees on separate valves; matched precipitation within a zone; head-to-head coverage for sprays; pressure regulation at the valve.
- Drip for trees and shrubs, smart controllers with seasonal adjustment, and a backflow prevention assembly tested annually by a certified tester.
- Local water-authority rules, such as Southern Nevada's turf limits and seasonal watering schedules, govern the palette and the schedule and override habit.
Planting and hardscape
- Right plant, right place: match sun exposure, water use, and mature size to the site. Plant trees at the root flare - buried trunks die slowly.
- Mulch 2-3 inches, kept off the trunk. Prune to ANSI A300; stake only when necessary and remove ties within a season.
- Concrete flatwork needs compacted base, adequate thickness, control joints, and expansion joints at fixed objects; pavers need edge restraint.
Worked example
A zone mixing rotors and spray heads runs short cycles; the sprays soak the turf while the rotors starve. Precipitation rates differ, so the fix is re-piping the zone to matched heads, not adding minutes.
Traps
'Water more' as a diagnosis; ignoring caliche or compaction; scheduling by habit rather than evapotranspiration; skipping backflow testing; burying the root flare.