Weed Patches Detection and Herbicide VRA Rx map
Goal: Detect weed patches from satellite imagery and generate an ON/OFF (2‑zone) herbicide prescription (Rx) you can export as SHP, ISOXML, or Send to John Deere.
When to use this workflow
Early–mid season when weed patches create clear spectral contrast vs. crop/soil.
Post‑emerge targeted sprays or patch‑spray clean‑ups.
Fields with known weedy headlands, drowned‑out spots, compaction bands, or prior escape areas.
Upsampling to 1 m improves map geometry (smoother polygons for controllers) but doesn’t invent new detail beyond the sensor’s native resolution.
Option A — Zoning Workflow (fastest)
Option B — Equation‑Based
Equation based map could also be used for VRA herbicide application map.
Q&A
Visual overlay: Toggle imagery + zones; check headlands and wetlands.
Spot‑check: 3–5 biggest patches on the ground or via high‑res drone/phone.
Edge artifacts: If you see boundary stripes, add boundary buffer (−3 to −6 m) or re‑threshold.
Cloud/shadow: If present, switch date or mask using the cloud layer.
Patches look noisy → Raise min area, add smoothing, or use Planet 3 m image.
Recommended defaults (tune per field)
Index: Start with OSAVI until canopy closes; try CIred‑edge from 6–9 leaf stage onward.
Min patch size: ≥ 2× section area (example: 12 m boom, 3 m section ⇒ ~72 m²). Round up for smoother control.
Buffers: −3 m field edge; no‑spray zones as per label/regulation.
Export tips by controller
SHP: Ensure attribute
RATE(numeric).ISOXML: Name the Operation type, Product, and Units exactly as your terminal expects.
Compliance & agronomy notes
Follow label rates, buffer zones, wind and drift rules.
Patch‑spray success improves if you re‑run this workflow 7–14 days after emergence for escapes.
Keep a before/after photo set to prove efficacy and refine thresholds next time.
Last updated
Was this helpful?