Substitution Pressure Before the Ribbon Cutting
A 2.3-acre corporate courtyard project specifies 28 balled-and-burlapped Acer rubrum ‘October Glory,’ 3-inch caliper, and 6 inches of tested topsoil with pH 6.0–7.0. Two days before planting, the contractor delivers 28 bare-root maples labeled ‘Red Sunset,’ 2.5-inch caliper, and submits an RFI stating that the specified cultivar is unavailable and that bare-root stock will establish faster. The contractor also provides a topsoil test showing pH 5.2 and proposes to “plant now and fertilize later” because the owner’s ribbon-cutting is in 10 days. The pay application requests 100% payment for planting, including trees not yet installed. The landscape architect is on site two days per week; the contractor has asked for verbal approval to proceed. The specifications require a written substitution request with horticultural data and a 30-day review period; the general conditions require written directives.
1. How should the landscape architect respond to the substitution request and the request for verbal approval?
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Do not give verbal approval. The submittal is a substitution request, not a simple RFI, and the specifications require written horticultural data and a review period. ‘Red Sunset’ is a different cultivar with different fall color and form, and bare-root 2.5-inch stock does not meet the specified 3-inch balled-and-burlapped size. The correct response is a written nonconformance: reject the delivered stock as not matching the approved submittal, direct its removal from the site, and require a complete substitution package if the contractor wants consideration. If the owner wants to accept it, document a credit for the smaller caliper and any increased maintenance risk, and obtain written owner approval plus the design professional’s recommendation. Allowing installation before approval would transfer leverage to the contractor and make rejection impractical.
2. What payment recommendation should be made on the pay application, and why?
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Recommend withholding payment for planting until the work is installed and accepted. The application seeks 100% payment for trees that are not in place, and the delivered trees are nonconforming. Stored materials are sometimes payable, but only when the contract allows it and when the materials are approved, insured, and stored off site or in a protected area. Here the stock should not be stored on site because it does not match the approved submittal. Certify only planting work actually completed and accepted, and note the tree and topsoil deficiencies in the payment certification. This protects the owner’s ability to require replacement and avoids paying for work that may be removed.
3. How should the topsoil pH problem be handled given the 10-day event?
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pH 5.2 is outside the specified 6.0–7.0 range. “Plant now and fertilize later” does not cure a pH problem; agricultural lime reacts over months and can injure roots if overapplied. Require the contractor to submit a remedial plan-either amend the topsoil with lime and retest, or source compliant topsoil-before planting. Retesting should be done by a qualified lab, at the contractor’s cost if the contractor supplied the material. The event date is a schedule risk, not a basis to waive the specification. Notify the owner in writing now that planting may be delayed or that acceptance of the lower pH carries establishment risk. If the owner directs acceptance, record it as a written owner decision with a credit or warranty adjustment.