Hartley Farm, Iowa
Corn · Growing Season 2026
—
Avg Health
—
Active Stakes
Digital Twin — 600 acres · 36 zones · — sensors
↑ N    ← W   E → Click zone to inspect
Zone Detail
Select a zone on the map above.
Legend
Optimal
Good
Fair
Poor
Critical
Sensor
Nitrogen Balance  ·  600 ac  ·  Current Season
↓ N Input
180lbs N/ac
Applied fertilizer
↑ N Losses
52.3lbs N/ac
↑Gas (N2O / NH3)
8.2 lbs/ac
→Surface runoff
12.4 lbs/ac
↓Ground leaching
31.7 lbs/ac
⇄ Net Flux
+127.7lbs N/ac
71% N-use efficiency
Retained in soil / crop
Select a zone to view trends
AI Recommendations
Select a zone
Click any zone on the field map to see zone-specific fertilizer recommendations.

Tierra Metrics
Business Plan

A staged commercialization strategy: enter the soil testing market now with IoT-connected sensor kits, generate near-term revenue, and use that foundation to build and launch the farm digital twin as our next major milestone.

$1.1B
US soil testing market · entering now
$7.5B
US precision ag market · 7.8% growth · next milestone
$0.70
Printed nitrate sensor cost, far below any competitor
Go-to-Market Strategy
Three-phase commercialization roadmap
Tierra Metrics enters the market through the soil testing segment, a large, underserved market where our low-cost printed sensors create an immediate competitive advantage. Revenue and field data from soil testing kit sales funds development of our digital twin platform, the next major product milestone.
Phase 1
Enter Soil Testing Market
2027 — IoT test kits · first customers
  • Launch IoT-connected soil testing kit: printed nitrate and pH sensors with GIS data logging: a rapid, field-deployable alternative to lab testing
  • Direct founder-led sales to early-adopter growers, agronomists, and soil testing labs in Iowa and Colorado
  • Deploy ~250 Smart Stakes; collect full-season validation data that doubles as ML training data
  • Co-design the sensor kit workflow with pilot users to ensure results are fast, accurate, and actionable
  • Publish peer-reviewed field validation results to support commercial claims
$55K
Target revenue
8
Partner farms
250
Stakes deployed
Phase 2
Scale Test Kits · Build Digital Twin
2028 — channel expansion · ML model training
  • Sign 3–5 ag retail and certified crop advisor (CCA) reseller agreements to distribute test kits
  • Apply for SBIR Phase I (target award Q1 2028) to fund hardware manufacturing scale-up
  • Begin training ML nitrogen cycle model on accumulated field sensor datasets
  • Issue first verified carbon credits through voluntary market registry
  • Hire first commercial sales representative and customer success lead
$710K
Target revenue
60
Partner farms
3,000
Stakes deployed
Phase 3
Digital Twin Launch · National Scale
2029–2030 — precision ag · 400 farms · ~300,000 acres
  • Launch digital twin SaaS platform: spatial ML model delivers zone-level fertilizer recommendations
  • National rollout via farm co-op networks and precision ag service providers
  • Expand to commodity crops beyond corn: soybeans, wheat, specialty crops
  • Launch international pilots in UK and EU markets leveraging Berkeley/CU partnerships
  • Series A raise (Q4 2028) to fund sales team expansion and manufacturing ramp
$5.3M
Target revenue
400
Partner farms
25,000
Stakes deployed
Dashboard Development
Built with farmers, not just for them
The pilot phase is a design phase as much as a validation phase. We use structured co-design sessions with partner farmers to ensure the Tierra Metrics dashboard delivers what growers actually need: clear, timely, actionable guidance and not just more data to interpret. Our goal is a tool that saves time, protects margins, and gives farmers genuine peace of mind going into each growing season.

Actionable by Design

Every dashboard alert links to a specific decision: adjust fertilizer rate, delay application, prioritize drainage. We measure success by whether a farmer can act on a recommendation without needing to call an agronomist, within seconds of opening the app.

Saves Real Time

The platform replaces time-consuming manual soil sampling, multi-week lab turnarounds, and fragmented record-keeping with continuous, automated monitoring and a clear weekly field summary. Early pilot feedback will drive how we surface this information most efficiently.

Peace of Mind

Real-time visibility into soil nitrogen status lets growers make confident, data-backed decisions rather than relying on intuition or outdated benchmarks, reducing the anxiety of over- or under-application and its downstream costs to yield, soil health, and the environment.

Financial Projections
Revenue forecast: FY2027 – FY2029
Four complementary revenue streams across two market segments. Soil testing kits and field IoT hardware generate near-term revenue while the digital twin SaaS platform is built; SaaS becomes the dominant recurring revenue driver by Year 3. Carbon markets provide a fourth stream tied to verified N2O emissions reduction.
Revenue Stream FY2027 FY2028 FY2029
Soil Testing Kits $15,000 $120,000 $350,000
Soil Intelligence IoT Hardware $10,000 $120,000 $400,000
Precision Ag SaaS $30,000 $420,000 $3,900,000
Carbon Markets (MRV) — $50,000 $600,000
Total Revenue $55,000 $710,000 $5,250,000
Gross Margin (est.) ~52% ~63% ~74%
Acres under management 2,000 30,000 300,000
Total Revenue Growth
FY2027
$55K
FY2028
$710K
FY2029
$5.25M
SaaS ARR Growth
FY2027
$30K
FY2028
$420K
FY2029
$3.9M
Projections are estimates based on current pipeline, market sizing, and comparable ag-tech company growth benchmarks. Not a guarantee of future performance.
Unit Economics
Capital-efficient model with improving margins at scale
Printed electronics dramatically reduce hardware COGS versus legacy sensor competitors. SaaS gross margins follow software norms. Combined LTV/CAC improves as channel partnerships reduce customer acquisition cost over time.
Hardware GM (early)
~60%
$100 sell / ~$40 COGS per stake. Printed ISE electrodes are the primary consumable cost driver.
Hardware GM (scale)
~58%
$12 sell / ~$5 COGS at volume. Printed electronics manufacturing scales favorably with roll-to-roll production.
SaaS Gross Margin
~85%
$13–15/acre/yr subscription. Cloud infrastructure and ML model inference are the primary variable costs.
Target LTV / CAC
> 5×
Multi-year SaaS contracts and annual ISE consumable replacement create durable recurring revenue per farm customer.
Customer Segments & Sales Channels
Two markets, three customer tiers
Phase 1 targets soil testing customers: labs, agronomists, and early-adopter growers ready to replace slow lab workflows. Phase 2 expands to full precision ag customers as the digital twin platform matures.

Soil Testing Labs & Agronomists Phase 1 · Entering Now

Target: Commercial soil testing labs and certified crop advisors (CCAs) who currently rely on $20, 7–21 day lab workflows. Tierra Metrics test kits deliver rapid, on-site nitrate and pH results with IoT logging at a fraction of the per-test cost. A direct replacement with a clear, immediate ROI.

Row Crop Producers Phase 1 + 2

Target: 200–2,000 acre corn, wheat, and soybean farms in the US Midwest and Plains. In Phase 1, sold as an IoT field testing kit. In Phase 2, upgraded to full precision ag SaaS: variable-rate application maps, digital twin modeling, and carbon MRV. Sold directly by founders in Year 1; via CCAs and ag retail in Years 2–3.

Food Companies & Government Phase 2 · Digital Twin

Target: Food and land-based corporations monitoring supply chain sustainability ($0.5–2.0M/company/yr), and state and federal agencies tracking agricultural pollution and emissions. Largest contract revenue per engagement, unlocked by the digital twin platform's verified monitoring capabilities.

Key Milestones
Execution roadmap: 2027 – 2030
Milestone-gated development ensures capital efficiency and investor transparency. Test kit sales generate early revenue while the digital twin is built; non-dilutive funding carries the company through commercial launch of both products.
Timeline Milestone Significance
Q1 2027 IoT soil testing kit product launch, starting with first kit sales to agronomists and growers Enters $1.1B soil testing market; generates first revenue and field training data
Q1 2027 First paid field pilot contracts signed (3–5 farms) Validates product-market fit and willingness to pay; anchors first case studies
Q2 2027 NSF SBIR Phase I application submitted ($275K) Non-dilutive grant targeting sensor R&D, field validation, and ML model development
Q3 2027 Peer-reviewed field validation paper published Establishes scientific credibility; supports commercial and carbon credit claims
Q1 2028 NSF SBIR Phase I award received ($275K); first reseller agreement signed Non-dilutive milestone validates technology; channel partner accelerates test kit distribution
Q2 2028 ML nitrogen cycle model trained; digital twin alpha with pilot farms Transitions company into precision ag market; unlocks second revenue stream
Q3 2028 First verified N2O carbon credits issued Opens fourth revenue stream; differentiates from pure precision-ag competitors
Q4 2028 Series A raise ($4–6M target) Funds national sales expansion, digital twin commercial launch, and manufacturing ramp
Q2 2029 300,000 acres under management; break-even on operations Demonstrates scalable unit economics across both market segments
Funding Strategy
Non-dilutive first, equity second
Tierra Metrics is deliberately structured to maximize non-dilutive capital before taking on equity investment, preserving founder and team ownership while de-risking the business for future investors.
Secured: ARPA-E Project
Undisclosed
Non-dilutive. Supported initial sensor design, ML model architecture, and early lab validation at CU Boulder and UC Berkeley.
Targeting:NSF SBIR Phase I
$275,000
Non-dilutive. Application Q2 2027; award targeted Q1 2028. Funds sensor R&D, field validation, and customer discovery.
Targeting:NSF SBIR Phase II
$2,000,000
Non-dilutive. Follows Phase I award (~2029). Funds hardware manufacturing scale-up, platform development, and national commercial launch.
Targeting:Seed Round
$1,500,000
Equity. Following Phase II award. Funds first commercial hires, channel partnership development, and carbon MRV infrastructure.
Targeting:Series A
$4–6,000,000
Equity. Q4 2028 target. Funds national sales expansion, international markets, and manufacturing ramp to $12/stake unit cost.
Risk & Mitigation
Key risks and how we address them
Risk Level Mitigation
Sensor drift & field reliability
Printed ISE electrodes may degrade faster than legacy sensors in harsh field conditions		 Medium 64+ days of continuous field validation data in hand. Consumable ISE replacement model designed into business. Ongoing reliability testing underway.
Grower adoption inertia
Farmers are risk-averse; changing practices requires demonstrated ROI		 Medium Pilot-first approach removes upfront financial risk. Case studies will quantify $ savings per acre. CCA channel leverages existing trusted advisor relationships.
Hardware manufacturing scale-up
Reaching $12/stake unit cost requires high-volume printed electronics production and smart stake manufacturing		 Medium CU Boulder and UC Berkeley manufacturing partnerships provide a path to roll-to-roll printed electronics at scale. SBIR Phase I/II funding is being pursued explicitly to fund this transition.
Carbon credit market volatility
Voluntary carbon markets have experienced price and liquidity instability		 Low Carbon credits are the third revenue stream, not the primary driver. Business model is viable on hardware + SaaS alone. Compliance markets (Section 45Z, USDA) provide a parallel pathway.
Larger competitor entry
Well-funded ag-tech or sensor companies could replicate the platform		 Low 6 licensed patents from CU Boulder and UC Berkeley create defensible IP moat. Printed ISE technology for in-situ nitrate sensing is not commercially available from any competitor.

Smarter Farming Through
Precision Soil Intelligence

Tierra Metrics works with growers and land managers to monitor soil and reduce fertilizer overuse, saving money and time while making agriculture more resilient.

1.9M
US farms under fertilizer cost pressure[1]
45%
of applied N actually increases crop yield[2]
$70K
annual fertilizer spend for an average-sized farm[3]
Soil heatmap 1 Soil heatmap 2 Soil heatmap 3
The Problem
Fertilizer overuse is the most serious problem in agriculture. Actionable data can save money and protect soil health in the long term.

Economic Waste

US farms waste an average of $125 per acre[4] on unnecessary nitrogen fertilizer for corn. Across a 560-acre operation, that's $70,000 per year going into the ground unused, not into yield. With nitrogen markets subject to extreme price volatility driven by energy costs and geopolitical supply disruptions,[5] improved fertilizer efficiency is also a matter of US food security.

Environmental Damage

Excess nitrogen leaches into groundwater and surface water, causing toxic algal blooms and dead zones.[6] It also escapes as nitrous oxide (N2O), a greenhouse gas 273–300× more potent than CO2.[7] Nitrate contamination further threatens drinking water safety and drives up municipal water treatment costs.[8] Fertilizer application must be tailored to sites to protect ecosystem health.[9]

No Real-Time Visibility

US farmers make billions of dollars worth of fertilizer decisions based on data that's months or years old.[10] Farmers already use testing kits, lab services and visual inspection to try to track their soil health.[11] In-situ sensors and digital twins can unlock new frontiers from precision agriculture to smart agriculture.[12]

Our Strategy
Earn while we build: disrupt soil testing today, deliver the digital twin tomorrow
Phase 1  ·  Now

Disrupt the Soil Testing Market

The $1.1B US soil testing market is ripe for disruption. Today's standard is slow, expensive lab testing: $20 per sample, 7–21 day turnaround, no real-time feedback, and hazardous reagents. Low-cost benchtop soil testing kits are already beginning to replace lab services, but they remain manual and colorimetric.

Tierra Metrics replaces this workflow with IoT-connected printed sensor kits. This means rapid, accurate nitrate and pH measurements at a fraction of legacy sensor or lab processing cost, with GIS-mapped results delivered instantly to any device. No lab. No wait. No reagents.

  • $0.70 printed nitrate sensor, far below any competitor
  • Field or benchtop deployment on the same sensor platform
  • IoT telemetry + GIS mapping built in
  • Generates revenue and builds the training dataset for our AI model
$1.1B US market[17]
→
Phase 2  ·  Next Milestone

Farm Digital Twin

Revenue from Phase 1 funds the development of our most powerful offering. Field data collected through IoT sensor deployments trains our machine learning models to build a real-time nitrogen cycle digital twin for each farm.

The digital twin fuses sensor data, remote sensing, historical records, and fertilizer pricing to generate zone-level application recommendations, telling growers exactly where and when to apply nitrogen, and how much. Variable-rate application cuts fertilizer use 20–40% with no yield penalty.[13]

  • Spatial ML model of soil nitrogen dynamics
  • Per-quadrant fertilizer recommendations
  • Remote sensing + sensor data fusion
  • Verified emissions data for carbon credit eligibility
$7.5B US market  ·  7.8% annual growth[16]
Market Opportunity
One core technology platform, two distinct and growing markets
Segment 1 · Entering Now
Soil Testing Equipment
In-Field & In-Lab
$1.1B[17]
US soil testing market
5%
Annual market growth
Status quo: Annual or 2–3 year lab testing: slow, costly, no real-time data
Tierra Metrics: Low-cost, rapid, IoT-enabled sampling with GIS integration
Segment 2 · Next Milestone
Precision Nutrient Management
Digital Twin & AI Analytics
$7.5B[16]
US precision ag market
9%
Annual market growth
Status quo: Fertilizer overuse by 50%, costing growers up to 40% of input spend
Tierra Metrics: Digital twin informs precise, zone-level nutrient application
$24B[15]
US nitrogen fertilizer market annually
880M[1]
Total US farmland acres across 1.9M farms
1.9M[1]
US farms under fertilizer cost pressure
$2B+[14]
Voluntary carbon market for agriculture
Revenue Model
Near-term hardware revenue funds the path to SaaS at scale

Phase 1: IoT Test Kit Hardware

Sensor kit sales to soil testing labs, agronomists, growers, and government entities. Printed ISE sensors for nitrate and pH at radically lower cost than existing options. IoT-enabled with built-in GIS data logging. Designed for both benchtop and in-field use.

$0.70 sensor cost · kit pricing TBD

Phase 2 · Digital Twin SaaS

Annual subscription for the Tierra Metrics precision ag platform: AI recommendation engine, spatial digital twin, variable-rate application map exports, and remote sensing data fusion. Co-designed with farmers. Priced per acre, scaling with farm size.

~$15–40 / acre / yr

Carbon Credits

Verified reduction in N2O emissions unlocks carbon credit revenue through voluntary and compliance carbon markets. MRV data is provided directly by our sensor network, a unique advantage over competitors without continuous in-situ monitoring.

$15–50 / tonne CO2e

Enterprise & Government

Custom sensor platforms for food and land-based corporations monitoring supply chain sustainability, and for state and federal agencies tracking agricultural pollution and emissions. Larger contract revenue per engagement.

$0.5–2.0M / company / yr
Competitive Advantage
Printed electronics: the key to scalable, affordable soil sensing

Tierra Metrics Smart Stake

  • +Screen-printed ion-selective electrodes for nitrate & pH. No lab needed
  • +Integrated moisture, temperature & O2 in a single probe allow for rapid emissions estimates
  • +Continous in-situ readings at configurable frequency
  • +ESP32 telemetry · low power · remote field compatible
  • +Unit economics enable dense field-wide deployment
  • +AI platform generates actionable VR application maps
  • +Optimized, low cost and low power potentiometric readout platform

Legacy / Competitors

  • -Expensive lab soil tests mean days to weeks for results
  • -Annual or seasonal sampling only. No real-time data
  • -High per-sensor cost limits coverage to a few points per field
  • -No in-situ nitrate or pH sensing. Moisture & temperature only
  • -No integrated AI analytics or fertilizer recommendations
  • -No verified emissions data for carbon credit eligibility
  • -Expensive, bespoke deployments required for in-situ data
References

The Tierra Metrics Team

Built at the intersection of environmental engineering, printed electronics, and precision agriculture. Our team combines deep technical expertise with real-world field deployment experience.

UK field
Founders
World-class expertise in soil science, sensors, and printed electronics
Whendee Silver
Prof. Whendee Silver
Co-Founder · Soil Biogeochemistry & AI/ML
University of California, Berkeley
Measures and models agricultural biogeochemical flows with a focus on nitrogen and carbon cycling. Leading the development of Tierra Metrics' AI/ML sensor data fusion system, bringing expertise in how soil chemistry dynamics translate to actionable agronomic insight.
Soil Biogeochemistry Nitrogen Cycling AI/ML for Soil Data
Gregory Whiting
Prof. Gregory Whiting
Co-Founder · Soil Sensor Design
University of Colorado, Boulder
Designs and deploys soil-health focused sensors with a particular emphasis on low-cost, field-deployable instrumentation. Leading sensor architecture and the fabrication of printed ion-selective electrodes for nitrate and pH measurement at the core of the Smart Stake.
Sensor Design Soil Health Instrumentation ISE Fabrication
Ana Claudia Arias
Prof. Ana Claudia Arias
Co-Founder · Printed Electronics
University of California, Berkeley
Researches and commercializes novel printed electronics for flexible, low-cost sensing applications. A key contributor to the printed sensor technology underlying the Smart Stake, leading manufacturing processes that enable scalable, affordable sensor production.
Printed Electronics Flexible Sensors Commercialization
Core Team
Building and deploying the technology
Taylor Sharpe
Dr. Taylor Sharpe
Chief Engineer
University of Colorado, Boulder · Tierra Metrics, Inc.
Over a decade of experience designing and deploying low-cost environmental sensor systems from rural water infrastructure in Nigeria and Rwanda to soil monitoring in the US and UK.
IoT Sensor Networks Field Deployment Human-centered Design
EE
Electrical Engineer
Hiring · Hardware & Embedded Systems
Boulder, Colorado
We are actively hiring an electrical engineer to join the core team and lead hardware development for the Smart Stake system: PCB design, embedded firmware, power systems, and sensor integration.
PCB Design Embedded Firmware Hardware Development
Institutional Partnerships
Built on a foundation of world-class research
University of Colorado Boulder
University of Colorado, Boulder
Home institution of founder Gregory Whiting. Tierra Metrics holds patent licenses from CU Boulder covering core sensor technologies. Taylor Sharpe serves as Instructor and Postdoctoral Research Associate in the CEAE and Mechanical Engineering departments.
University of California, Berkeley
University of California, Berkeley
Home institution of founders Ana Arias and Whendee Silver. Tierra Metrics holds patent licenses from UC Berkeley covering printed electronics technologies developed by the Arias Lab.
NSF & ARPA-E
An ARPA-E project supported initial sensor design and ML modeling. NSF I-Corps program supported 100+ customer discovery interviews with US growers and agronomists.
Intellectual Property
Tierra Metrics holds exclusive licenses to 6 patents from CU Boulder and UC Berkeley covering core sensor fabrication, readout electronics, and sensor network architectures. Four patents are fully held; two additional licenses are underway.
Patents Held
63/650,372
Two-Terminal pH Sensor with Simple Readout Electronics
Enables a simplified, low-cost potentiometric readout circuit that removes the need for a separate reference electrode, a key driver of the platform's low unit cost.
PCT/US2022/034394
Fully Printed Organic Electrochemical Transistors with Internal Ion Reservoirs for Detecting Macronutrients in Raw Plant Sap
Printed transistor-based sensors for direct macronutrient detection in plant sap. Enables a new class of direct plant health monitoring complementary to soil sensing and a future product expansion opportunity.
PCT/US2023/072886
Printed Multi-Analyte Disposable Electronic Sensor Strip for Agriculture
Directly covers the test kit product to support rapid soil health assessment: a low-cost, single-use sensor consumable that can measure multiple soil ions simultaneously in field or benchtop conditions.
63/634,317
Hybrid Parallel Decomposition / Microbial Activity / Enzymatic Activity Sensors Printed on PCB Substrates
Sensors for soil biological activity: microbial and enzymatic processes that directly drive nitrogen cycling. Positions Tierra Metrics to measure the biological dimension of soil health, beyond chemistry alone.
Licensing Underway
PCT/US2024/037365
Optimized Distribution of Wireless Sensors Based on Radial Values
Algorithmic approach to optimal sensor placement across a field based on spatial signal analysis. Directly supports the Smart Stake deployment workflow and the digital twin's spatial interpolation model.
PCT/US2022/076527
Biodegradable Potentiometric Sensor to Measure Ion Concentration in Soil
A biodegradable in-situ ion sensor for soil. Enables a future generation of environmentally benign, fully compostable sensors which could eliminate field retrieval and reduce lifecycle costs for large-scale deployments.

Team Publications

Tierra Metrics is built on a foundation of peer-reviewed research. The papers below were authored or co-authored by our team and represent the scientific backbone of the company's sensor technology, nitrogen cycle modeling, and field deployment expertise.

Soil pH plot
Printed Soil Sensors
The core sensor technology behind the Smart Stake and test kit platform
Baumbauer et al. · Sensors · 2022
Printed Potentiometric Nitrate Sensors for Use in Soil
C.L. Baumbauer, P.J. Goodrich, M.E. Payne, T. Anthony, C. Beckstoffer, A. Toor, W. Silver, A.C. Arias
Fully printed ion-selective electrodes achieved −48 mV/decade nitrate sensitivity across a 0.62–6200 ppm range in both aqueous solution and peat soil. This is the foundational sensor paper directly underlying the Smart Stake's printed nitrate ISE.
doi.org/10.3390/s22114095
Toor et al. · ACS Omega · 2024
Printed Potentiometric Ammonium Sensors for Agriculture Applications
A. Toor, P. Goodrich, T.L. Anthony, C. Beckstoffer, H. Jegan, W.L. Silver, A.C. Arias
Printed ammonium ISEs validated in sand, peat, and clay soils at 53–58 mV/decade sensitivity, enabling direct real-time measurement of plant-available nitrogen alongside the nitrate sensor.
doi.org/10.1021/acsomega.4c05746
Crichton et al. · IEEE Sensors Journal · 2025
Two-Electrode Screen-Printed pH Sensors for Monitoring Soil and Other Growing Media
C.A. Crichton, L. Lahann, J.P.C. Barba, T. Yuan, E.J. Strand, N. Bruno, P.J. Goodrich, C.L. Baumbauer, M. Atreya, E. Bihar, W.L. Silver, K.S.J. Pister, A.C. Arias, G.L. Whiting
A simplified two-electrode screen-printed pH sensor with an on-chip reference electrode was validated across multiple soil types and growing media. This directly covers the Smart Stake's pH sensing capability and enables the removal of a separate reference electrode.
doi.org/10.1109/JSEN.2025.3558158
Goodrich et al. · Advanced Sensor Research · 2025
Fully-Printed Ion Sensor Arrays for Measuring Agricultural Nitrogen and Potassium Concentrations Using Nernstian and AI Models
P. Goodrich, N. Poongovan, E. Strand, C. Schwendeman, L. Lahann, S. Koh, Y. Cai, C. Baumbauer, A. Toor, G.L. Whiting, A.C. Arias
An integrated printed array combining nitrate, ammonium, and potassium ISEs with both classical and AI-based calibration models for simultaneous multianalyte soil measurement, pointing toward the multi-parameter sensing capability of future Smart Stake generations.
doi.org/10.1002/adsr.202400121
Strand et al. · Advanced Electronic Materials · 2022
Printed Organic Electrochemical Transistors for Detecting Nutrients in Whole Plant Sap
E.J. Strand, E. Bihar, S.M. Gleason, S. Han, S.W. Schreiber, M.N. Renny, G.G. Malliaras, R.R. McLeod, G.L. Whiting
Fully printed OECTs were used to detect potassium concentrations directly in plant sap, enabling real-time in-planta macronutrient monitoring. This capability underlies the patent for macronutrient detection in raw plant sap and points toward future product expansion beyond soil sensing.
doi.org/10.1002/aelm.202100853
Strand et al. · Sensors and Actuators B · 2023
Multimodal Operation of Printed Electrochemical Transistors for Sensing in Controlled Environment Agriculture
E.J. Strand, M.J. Palizzi, C.A. Crichton, M.N. Renny, E. Bihar, R.R. McLeod, G.L. Whiting
A flexible screen-printed transistor simultaneously measured conductivity, temperature, and pH in an active hydroponic system using a single device. Demonstrates the multimodal sensing capability that informs the Smart Stake's integrated parameter measurement architecture.
doi.org/10.1016/j.snb.2023.133763
Biodegradable and Transient Electronics
Toward compostable, zero-retrieval sensor deployment
Atreya et al. · Advanced Science · 2023
A Transient Printed Soil Decomposition Sensor Based on a Biopolymer Composite Conductor
M. Atreya, S. DeSousa, J-B. Kauzya, E.G. Williams, A.C. Hayes, K. Dikshit, J. Nielsen, A. Palmgren, S. Khorchidian, S. Liu, A. Gopalakrishnan, E. Bihar, C.J. Bruns, R. Bardgett, J.N. Quinton, J. Davies, J.C. Neff, G.L. Whiting
A biodegradable resistive sensor printed with a PHBV-based conductor degrades at a rate proportional to microbial activity in soil, providing a low-cost distributable proxy for soil health. This technology underlies the biodegradable sensor IP now being licensed by Tierra Metrics.
doi.org/10.1002/advs.202205785
Sharpe et al. · Computers and Electronics in Agriculture · 2026
In-Situ Decomposition Sensor Output Correlates with Soil Health Indicators
T.J. Sharpe, M. Atreya, S. Liu, M. Gong, N. Luna, N. Smock, J. Davies, J. Quinton, R. Bardgett, J.C. Neff, R. Killick, G.L. Whiting
Field validation of the biodegradable decomposition sensor across multiple agricultural sites, showing its resistive output correlates significantly with microbial respiration and enzyme activity. Co-authored by Tierra Metrics Chief Engineer Taylor Sharpe.
doi.org/10.1016/j.compag.2026.111427
Sui et al. · ACS Sustainable Chemistry & Engineering · 2021
Controlled Biodegradation of an Additively Fabricated Capacitive Soil Moisture Sensor
Y. Sui, M. Atreya, S. Dahal, A. Gopalakrishnan, R. Khosla, G.L. Whiting
A "bury and forget" capacitive soil moisture sensor using biodegradable zinc electrodes and PHBV binder, designed to function through a growing season and then degrade harmlessly in soil. This work provides the scientific basis for the biodegradable potentiometric soil sensor patent being licensed by Tierra Metrics.
doi.org/10.1021/acssuschemeng.0c09485
Atreya et al. · ACS Applied Electronic Materials · 2022
Wax Blends as Tunable Encapsulants for Soil-Degradable Electronics
M. Atreya, G. Marinick, C. Baumbauer, K.V. Dikshit, S. Liu, C. Bellerjeau, J. Nielson, S. Khorchidian, A. Palmgren, Y. Sui, R. Bardgett, D. Baumbauer, C.J. Bruns, J.C. Neff, A.C. Arias, G.L. Whiting
Beeswax/soy wax blends were characterized as tunable biodegradable encapsulants whose blend ratio controls both degradation timing and mechanical protection for printed electronics in soil, enabling the seasonal durability and eventual biodegradation of future Tierra Metrics sensor consumables.
doi.org/10.1021/acsaelm.2c00833
Baumbauer et al. · Advanced Electronic Materials · 2024
Polycaprolactone-Based Zinc Ink for High Conductivity Transient Printed Electronics and Antennas
C.L. Baumbauer, A. Gopalakrishnan, M. Atreya, G.L. Whiting, A.C. Arias
A biodegradable zinc ink achieves conductivity up to 6 × 105 S/m and was used to fabricate UHF-RFID dipole antennas operating at 915 MHz, enabling wireless communication for fully transient agricultural sensor nodes and opening a path to zero-retrieval IoT deployment at scale.
doi.org/10.1002/aelm.202300658
Dahal et al. · Sensors · 2020
Degradability of Biodegradable Soil Moisture Sensor Components and Their Effect on Maize Growth
S. Dahal, W. Yilma, Y. Sui, M. Atreya, S. Bryan, V. Davis, G.L. Whiting, R. Khosla
Greenhouse maize trials evaluated five biodegradable materials for soil sensors, confirming that a beeswax/soy wax blend provided optimal stability and that none of the candidate materials adversely affected crop growth, establishing agronomic safety for in-soil biodegradable sensor deployment.
doi.org/10.3390/s20216154
Sensor Networks and Field Deployment
Optimizing where sensors go and how data gets collected
Goodrich et al. · Computers and Electronics in Agriculture · 2023
Placement and Drone Flight Path Mapping of Agricultural Soil Sensors Using Machine Learning
P. Goodrich, O. Betancourt, A.C. Arias, T. Zohdi
A machine learning algorithm optimally positions distributed soil sensors across a field and maps drone flight paths for deployment and readout, directly informing the spatial coverage strategy and GIS integration of the Tierra Metrics sensor network. This underlies the wireless sensor distribution patent being licensed by the company.
doi.org/10.1016/j.compag.2022.107591
Soil Nitrogen Dynamics
The science of what sensors need to measure and why it matters
Anthony & Silver · Nature Communications · 2023
Carbon-Sink Potential of Continuous Alfalfa Agriculture Lowered by Short-Term Nitrous Oxide Emission Events
T.L. Anthony, D.J. Szutu, J.G. Verfaillie, D.D. Baldocchi, W.L. Silver
Four years of continuous monitoring showed that irrigation-triggered N2O hot moments lasting less than 1% of the year account for up to 57% of annual emissions, substantially offsetting the ecosystem's carbon sink. This finding directly motivates the need for high-frequency continuous soil monitoring rather than periodic sampling.
doi.org/10.1038/s41467-023-37391-2
Anthony & Silver · Global Change Biology · 2021
Hot Moments Drive Extreme Nitrous Oxide and Methane Emissions from Agricultural Peatlands
T.L. Anthony, W.L. Silver
Three years of automated chamber measurements in an agricultural peatland found that brief N2O and CH4 pulses triggered by rapid soil oxygen depletion dominate annual greenhouse gas budgets. This work motivates the Smart Stake's combined N, O2, and moisture sensing capability for capturing these critical but ephemeral emission events.
doi.org/10.1111/gcb.15802
O'Connell et al. · Frontiers in Forests and Global Change · 2022
Utilizing Novel Field and Data Exploration Methods to Explore Hot Moments in High-Frequency Soil Nitrous Oxide Emissions Data
C.S. O'Connell, T.L. Anthony, M.A. Mayes, T. Pérez, D. Sihi, W.L. Silver
Reviews methods for detecting and analyzing rare but extreme N2O emission events in continuous sensor data streams, highlighting both the opportunity and the analytical challenge that high-frequency soil monitoring creates. Addressing this challenge is a core function of the Tierra Metrics ML pipeline.
doi.org/10.3389/ffgc.2022.674348
Yang et al. · Soil Biology and Biochemistry · 2017
Cross-Biome Assessment of Gross Soil Nitrogen Cycling in California Ecosystems
W.H. Yang, R.A. Ryals, D.F. Cusack, W.L. Silver
Gross N cycling rates measured across 33 California sites in 5 biomes found that soil moisture and carbon-to-nitrogen ratios are the strongest predictors of N mineralization. These two parameters are central to the Smart Stake's sensor suite and the nitrogen cycle digital twin model.
doi.org/10.1016/j.soilbio.2017.01.004
Yang et al. · Nature Geoscience · 2012
Nitrogen Loss from Soil Through Anaerobic Ammonium Oxidation Coupled to Iron Reduction
W.H. Yang, K.A. Weber, W.L. Silver
Demonstrated a previously unrecognized soil nitrogen loss pathway (Feammox) in which ammonium is oxidized under anaerobic conditions coupled to iron reduction. This fundamental biogeochemistry, discovered by Prof. Silver's group, informs the nitrogen cycle model underlying the Tierra Metrics digital twin.
doi.org/10.1038/ngeo1530
Almaraz et al. · JGR Biogeosciences · 2023
Dinitrogen Emissions Dominate Nitrogen Gas Emissions from Soils with Low Oxygen Availability in a Moist Tropical Forest
M. Almaraz, P.M. Groffman, W.L. Silver, S.J. Hall, Y. Lin, C.S. O'Connell, S. Porder
Soil incubations from a moist tropical forest demonstrate that N2 dominates nitrogen gas losses from low-oxygen soils, with implications for how nitrogen budgets are estimated. Understanding oxygen dynamics in soil, measured directly by the Smart Stake, is critical for accurately modeling nitrogen availability to crops.
doi.org/10.1029/2022JG007210
Ryals et al. · Ecological Applications · 2015
Long-Term Climate Change Mitigation Potential with Organic Matter Management on Grasslands
R. Ryals, M.D. Hartman, W.J. Parton, M.S. DeLonge, W.L. Silver
Field data and DAYCENT biogeochemical modeling showed that a single compost application provides significant long-term carbon sequestration potential on rangelands. Demonstrates the type of long-term soil carbon and nitrogen data that the Tierra Metrics digital twin is designed to monitor and verify at scale.
doi.org/10.1890/13-2126.1
Parton et al. · Science · 2007
Global-Scale Similarities in Nitrogen Release Patterns During Long-Term Decomposition
W. Parton, W.L. Silver, I.C. Burke, L. Grassens, M.E. Harmon, W.S. Currie, J.Y. King, E.C. Adair, L.A. Brandt, S.C. Hart, B. Fasth
A landmark 10-year multi-site study found that net nitrogen release from decomposing litter is driven primarily by initial tissue N concentration regardless of climate or biome, providing foundational insight into the soil nitrogen dynamics that Tierra Metrics' digital twin models.
doi.org/10.1126/science.1134853

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The Smart Stake: Soil Sensing at Scale

Tierra Metrics' core innovation is a printed-electronics sensor stake that measures critical soil parameters continuously in-situ, at a unit cost that makes dense, field-wide deployment economically viable for the first time. Sensor data fusion drives an advanced machine learning model that provides a digital twin of the agricultural Nitrogen cycle.

AI Analytics
Printed Electronics
6
Patent options from CU Boulder & UC Berkeley
100+
Farmer interviews via NSF I-Corps
System Architecture
How the Smart Stake works
A single stake deployed in the field houses a configurable set of sensors, a microcontroller, and an ESP32 telemetry module. Data is transmitted every 15 minutes to a farm or remote gateway and on to the Tierra Metrics cloud platform.
Smart Stake
IP68 cable glands pass electrical cables from individual sensors through the housing.
PCB substrates of a common geometry support various printed sensors.
The sensor PCB serves as a sealing surface to protect internal components from water intrusion.
The gas flux chamber is isolated from the rest of the SmartStake. A printed soil moisture sensor wraps around the gas flux chamber using a flexible substrate.
The assembled SmartStake is approximately 25 cm in length and can be fully installed in the soil.
SOIL SURFACE 0 in 12 in 24 in 36 in TOPSOIL SUBSOIL SUBSTRATUM ESP32 MODULE Soil pH Printed ion-selective electrode · range 4–9 Nitrate Printed ISE · 2–80 ppm · ±2 ppm accuracy Soil Moisture Capacitive sensor · 10–90% Temperature Thermistor · ±0.5°F · 40–95°F Soil O2 Concentration Optical ยท N2O flux proxy Sub-GHz Antenna 15-min transmit · 10 km+ range Active / transmitting ← Data to cloud platform
Hardware Prototypes
Sensor components: lab and field validation
We haven't just imagined soil health sensing solutions. We've built them. All sensor types have been fabricated in-house and deployed in active agricultural fields. The nitrate ISE and pH ISE are manufactured using screen-printing processes with a target unit cost of $12 at scale.
Printed ISE sensors
Printed Ion-Selective Electrode (ISE) Sensors
Screen-printed nitrate and pH sensors on flexible substrate. Manufactured using low-cost printing processes. Designed for direct in-soil deployment with no sample preparation required. Cutting edge potentiometric approaches minimize sensor signal drift.
Moisture O2 Temp probe
Moisture, O2 & Temperature Probe
Integrated cylindrical probe measuring soil moisture (capacitive), dissolved oxygen (optical), and temperature (thermistor) simultaneously. These proxy measurements can unlock real-time nitrous oxide emissions monitoring in agricultural soils.
Nitrogen cycle diagram
Modeling and AI Analytics
The complex dynamics that control nutrient levels in soils require continuous monitoring, informed modeling, and high-level expertise to deliver actionable insights. Sensor data fusion can enable real-time variable rate nitrogen application recommendations.
Field Validation Data
In-situ pH data: 64 days, 15-minute sampling
Continuous pH measurements from a field-deployed prototype, April 21 – June 24, 2025. Data collected every 15 minutes with no human intervention. The initial rise reflects sensor equilibration with soil chemistry after insertion; readings stabilize within the first week of deployment. This is the highest-frequency soil pH data ever collected.
STAT V2 Enclosure
Printed pH sensor and weatherized datalogger
pH animation
Cutting-edge printed electronics avoid pH sensor drift using peak-finding potentiometric sensing.
Measured Soil pH — Field Deployment 2025
Apr 21 – Jun 24  ·  15-min sampling interval  ·  Optimal range: 6.0 – 7.0
Sensor Specifications
Technical parameters
Parameter Sensing Method Range Accuracy Sample Rate Status
Soil pH Printed ion-selective electrode (ISE) 4 – 9 pH ±0.2 pH 15 min Field Validated
Nitrate (NO3−) Printed ISE (electrochemical) 2 – 80 ppm ±2 ppm 15 min Field Validated
Soil Moisture Capacitive dielectric 10 – 90% VWC ±2% 15 min Field Validated
Temperature Thermistor (NTC) 40 – 95 °F ±0.5 °F 15 min Field Validated
Soil O2 Concentration Optical luminescence quenching 0 – 20 mg/L ±0.3 mg/L 1 hr Prototype
Wireless (mesh) ESP32 ESP-NOW Up to 1 km — 15 min Field Validated
Wireless (gateway) WiFi / Cellular / Satellite — — Daily Field Validated
Battery life Lithium primary cell — — — 12+ months growing season
Log Fertilizer Application
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