Rhode Island's extension doesn't run its own soil-test calibration lab; it refers growers to neighboring-state methods. Zone Forge uses that published referral and discloses it in-app — no pretend precision. URI Cooperative Extension Gardening Information and Soil Testing (GIST, 2026) — URI runs only a free pH/texture service and explicitly refers full-nutrient testing to UConn SNAL or UMass SPNT (both Modified Morgan). rhode_island_uri v1.0 documents the URI referral pathway and inherits per-crop calibration from umass_smp_sikora (UMass selected as primary for proximity + receiving-lab convention; UConn equally defensible). RI will never be 'calibrated' status under audit definition — RI has no own land-grant publication. Lime continues to route via uconn_smp_sikora (SMP/Sikora). Replaces prior penn_state_2024 + modified_morgan_to_m3 conversion routing — that route was structurally wrong because UConn/UMass use Modified Morgan natively (no M3 conversion needed) and PSU's M3 calibration is PA-specific.
Published source: Rhode Island — URI Cooperative Extension referral pathway → UMass Soil & Plant Nutrient Testing Laboratory
Rhode Island refers growers to neighboring-state calibrations. URI Cooperative Extension Gardening Information and Soil Testing (GIST, 2026) — URI runs only a free pH/texture service and explicitly refers full-nutrient testing to UConn SNAL or UMass SPNT (both Modified Morgan). rhode_island_uri v1.0 documents the URI referral pathway and inherits per-crop calibration from umass_smp_sikora (UMass selected as primary for proximity + receiving-lab convention; UConn equally defensible). RI will never be 'calibrated' status under audit definition — RI has no own land-grant publication. Lime continues to route via uconn_smp_sikora (SMP/Sikora). Replaces prior penn_state_2024 + modified_morgan_to_m3 conversion routing — that route was structurally wrong because UConn/UMass use Modified Morgan natively (no M3 conversion needed) and PSU's M3 calibration is PA-specific.
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Zone Forge reads every Rhode Island soil test in its own state's language, then builds source-cited fertilizer and lime recommendations and full variable-rate prescriptions. See the science →