Brown patches and weeds need a quick first assessment before you decide on treatment or a lab sample. Short answer: use ChatGPT (lists possible causes and field checks from photos and conditions). Free option: Google Lens. The workflow has 4 steps and 2 copy-paste prompt(s); expect a ranked list of possible causes with field checks, and a client note. Main caution: AI diagnosis is a starting point, not a confirmed diagnosis.
The problem
Brown patches and weeds need a quick first assessment before you decide on treatment or a lab sample.
Recommended tools
ChatGPTLists possible causes and field checks from photos and conditions.
Free; paid plans per user - see https://chatgpt.com/pricing
Google Lens
PictureThisPlant ID and disease diagnosis app.
Free download; Pro ~$39.99/yr (US App Store; varies)Editorial opinion based on the vendor capabilities and prices listed in our tools directory. Not paid placements; prices as checked Oct 2026 and may change. Compare all use cases →
All tools mentioned
Step-by-step workflow
- Photograph the problem close up and from a distance; note grass type, weather, irrigation, mowing height and fertilizer history.
- Use a university diagnostic resource (such as Purdue's Turf Doctor) and an AI assistant to list possible causes.
- Do the field checks suggested (tug test, soil probe, insect float test).
- Confirm with your extension office or a lab before chemical treatment.
Copy-paste prompts
I'm diagnosing a lawn problem. Grass: [type]. Symptoms: [pattern, color, size]. Conditions: [weather, irrigation, mowing height, recent fertilizer/chemicals]. Photos: [attach]. List the 3-5 most likely causes, the field check that confirms or rules out each, and when to send a sample to a lab. Don't recommend specific pesticide products.
Write a short client explanation of what we found [finding] and our recommended next step [step], in plain language.
What to expect
A ranked list of possible causes with field checks, and a client note.
Limits & safety
- AI diagnosis is a starting point, not a confirmed diagnosis.
- Pesticide use must follow the label and may require an applicator license.
Source / inspired by
- Purdue Turf Doctor — Purdue University. A turf diagnostic resource covering diseases, insects and weeds. Summarized in our own words.