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RECEIPTS

Data sources & credits

Every threshold we ship — the 12% drought floor, the dollar-spot pressure model, FAO-56 ET₀, the dewpoint band — traces back to a peer-reviewed paper or a public-domain government feed. This page lists every one of them, with the URL, the DOI, and what we use it for.

We don't believe in black boxes. If you can't cite it, you can't ship it.

Peer-reviewed papers

The agronomic engine.

  • Allen, R.G., Pereira, L.S., Raes, D., Smith, M. (1998)
    Crop Evapotranspiration — Guidelines for Computing Crop Water Requirements (FAO Irrigation and Drainage Paper No. 56)
    Food and Agriculture Organization of the United Nations
    The reference for ET₀ (reference evapotranspiration). TurfPulse uses the FAO-56 Penman-Monteith equation as the spine of the daily water-budget model — temperature, humidity, wind, and solar radiation in, mm/day of crop water demand out.
    Read paper
  • Smith, D.L., Kerns, J.P., Walker, N.R., Payne, A.F., Horvath, B., Inguagiato, J.C., et al. (2018)
    Development and validation of a weather-based warning system to advise fungicide applications to control dollar spot on turfgrass
    PLOS ONE 13(3): e0194216
    The Smith-Kerns dollar-spot model — a logistic regression on 5-day moving average relative humidity and daily mean temperature — predicts dollar-spot probability. TurfPulse runs this model nightly off your local NWS data and surfaces the score on the disease-pressure tile. The original paper validated a 20% spray threshold that cut fungicide use by up to 30% versus calendar-based programs across seven states.
    DOI: 10.1371/journal.pone.0194216 Read paper
  • Wherley, B.G. et al. (TAMU AgriLife Extension) (2014–2020)
    Soil moisture-based deficit irrigation thresholds for warm-season turfgrass cultivars on USGA-spec sand profiles
    Texas A&M AgriLife Extension — turfgrass research series
    The empirical basis for TurfPulse's 12% SVWC drought-floor override on bermudagrass. Wherley and colleagues at TAMU repeatedly identified SVWC ≈ 10–12% as the wilt-stress threshold on coarse-textured fairway profiles, with cultivar-level differences (TifTuf and Tahoma 31 sustain quality further into the dry-down). When CH1 (the DRY-zone probe) drops below 12%, TurfPulse overrides skip-gates and fires anyway — except where freeze or municipal blackout windows take precedence.
    Read paper
  • Christiansen, J.E. (1942)
    Hydraulics of Sprinkling Systems for Irrigation (Bulletin 670)
    University of California Agricultural Experiment Station
    The original Distribution Uniformity (DU) paper — the math that says a sprinkler delivers different rates across its arc, and the field method for measuring it with catch-cups. Step 5 of our methodology uses Christiansen's DU coefficient (~0.75 for residential pop-ups) to convert nominal precipitation rate into effective PR.
    Read paper
  • Latin, R., et al. (2021)
    Dollar Spot of Turfgrass: Biology, Epidemiology, and Management — Comprehensive Review
    Phytopathology — APS Journals
    The contemporary review backing TurfPulse's dewpoint-band advisory. Prolonged leaf wetness (>8–12 hours) — driven by overnight dew, high relative humidity, and dewpoints inside the 60–70°F band — is the dominant epidemiological driver. The dewpoint tile uses this band as the disease-pressure trigger.
    Read paper
  • University of Missouri Extension (Latest revision)
    IPM1029: Identification and Management of Turfgrass Diseases
    MU Extension
    Extension-grade reference for pre-emergent timing windows, leaf-wetness reduction strategies, and the 'irrigate deeply and infrequently between midnight and early morning' rule that TurfPulse encodes in its predawn-fire bias.
    Read paper
  • University of Georgia Extension (Latest revision)
    Circular 891: Turfgrass Pest Management Handbook
    UGA Cooperative Extension
    Cross-reference for warm-season disease pressure, fertility-by-season guidance, and the early-day dew-removal protocol that influences our 5:30 AM predawn anchor window.
    Read paper
  • Irrigation Association (Ongoing)
    Smart Water Application Technologies (SWAT) Testing Protocols
    Irrigation Association
    The 0.75″/session safe-runoff cap in Step 4 of the methodology comes from IA SWAT field-testing protocols — anything over that ponds on clay or drains past the root zone on sand. Both wasted.
    Read paper

Live data feeds

Government, public-domain, and licensed feeds we pull every 15 min.

FeedWhat we use it forLicenseSource
NOAA / National Weather ServiceAuthoritative US forecasts, freeze advisories, and severe-weather alerts. Used in skip-gate decisions and the freeze-window override.Public domain (US Gov)Source
Open-MeteoHourly forecast feed for ET₀ inputs (temp, RH, wind, solar) and the dewpoint band. Cached server-side; primary fallback when NWS is degraded.CC-BY-4.0 (commercial OK)Source
OpenWeatherBackup forecast feed for redundancy and international coverage.Commercial — paid tierSource
Weather Underground PWSPersonal Weather Station network — the local micro-station feed (KTXROUND935 in Round Rock) used to ground-truth the regional forecast.Commercial — PWS APISource
Ecowitt CloudSoil moisture (WH51 / WH52), soil temperature (WN34), 7-in-1 weather (WS90), and lightning detector feeds direct from your gateway. The probe-driven irrigation engine reads off this feed every 15 min.User-owned data via Ecowitt APISource
Rachio Public APIZone state, schedule dispatch, and skip events. TurfPulse fires zones via authenticated POST and listens for completion via polling.Commercial — Rachio Developer ProgramSource
TexasET Network (TAMU AgriLife)Texas-specific ET₀ baselines and crop coefficients (Kc) for warm-season turf. Used to ground-truth the FAO-56 calc against in-state stations.Public — TAMU AgriLifeSource
USDA NRCS Web Soil SurveyCounty-level soil texture profiles (sand/silt/clay %, available water capacity). Used to suggest realistic root-zone depths and runoff caps for new users.Public domain (US Gov)Source

Models & equations

The math, in one place.

Reference ET (ET₀)
FAO-56 Penman-Monteith

Allen et al. 1998. Daily mm of crop water demand for a 0.12 m short-grass reference. Inputs: T, RH, wind at 2 m, net radiation. Drives the water-budget tile and FAO-56-aligned MAD calculations.

Distribution Uniformity (DU)
Christiansen 1942

The catch-cup math: DU = 1 − (mean abs deviation / mean catch). Used to convert nominal nozzle PR into effective PR in Step 5 of the probe-driven runtime formula.

Dollar-spot risk
Smith-Kerns 2018

Logistic regression on 5-day moving avg RH + daily mean temp. Output is a 0–1 probability of dollar-spot occurrence — TurfPulse displays this as a 0–100 score with the 20% action threshold that the original paper validated.

Growing Degree Days (GDD)
Modified base-50 (turf) and base-55 (PGR rebound)

Daily accumulation of (mean temp − base), floored at 0. Drives pre-emergent windows, PGR re-application timing, and warm-season green-up alerts. We expose both base-50 and base-55 because the research literature uses both for different applications.

MAD (Management Allowed Depletion)
FAO-56 §8.2

The fraction of plant-available water (PAW) the root zone can lose before stress kicks in. We default to 0.50 for warm-season turf and gate fires when depletion exceeds it.

Drought floor override
Wherley TAMU AgriLife

Hard threshold at SVWC < 12% on the DRY-zone probe forces a fire regardless of skip-gates (except freeze and municipal blackout, which always win).

What we don't claim

  • FAO-56 is a reference crop, not your crop. ET₀ is short-grass at full canopy. Crop coefficients (Kc) for your actual species + condition introduce error of ±10–20%. The probe is the corrective ground-truth.
  • The 12% SVWC drought floor is bermuda-on-fine-sandy-loam. Cool-season grasses, organic-rich loam, and clay profiles behave differently. Inner Circle members can override the floor per cultivar.
  • Smith-Kerns is a probability, not a prediction. A 90% score doesn't mean dollar spot tomorrow — it means the weather is suitable for it. Cultural pressure (mowing, dew, N status) still has to align.
  • PWS data is as good as the station siting. A wunderground station next to an A/C exhaust will lie about RH. We surface station age + last-update so you can sanity-check.

Found a paper we should cite?

We update this page when new research lands. Email hello@turfpulse.app with the DOI and we'll add it.

See the methodology pageBack to TurfPulse

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