2026 Ohio, Indiana, Illinois, and Missouri Weed Control Guide
Ohio State; Purdue; Illinois; Missouri
How Meadowlark works
From field guides to cited answers.
We turn regional crop-protection guides into voice answers you can verify on screen.
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The guides behind the answers
The 12 guides below cover 14 states and provinces. Each one is registered for retrieval, routing, and citations, and edition cautions stay visible where the latest available source is older.
United States
9 guidesNorth Dakota Weed Control Guide, W253-26 (2026)
North Dakota State University Extension
2026 Chemical Weed Control for Field Crops, Pastures, Rangeland and Noncropland (Kansas)
Kansas State University Research and Extension
Recommended Chemicals for Weed and Brush Control, MP44 (2026, Arkansas)
University of Arkansas System Division of Agriculture
2026 Weed Management Suggestions for Mississippi Row Crops
Mississippi State University Extension
North Carolina Agricultural Chemicals Manual: Chemical Weed Control (2026)
NC State Extension
Weed Control Recommendations for Kentucky Grain Crops, AGR-6 (2026)
University of Kentucky Cooperative Extension
2026 Weed Control Guide for Field Crops (Michigan State University)
Michigan State University Extension
Pest Management in Wisconsin Field Crops, A3646 (2025)
University of Wisconsin-Madison Division of Extension
latest openly available edition
Canada
3 guides2026 Manitoba Guide to Crop Protection
Manitoba Agriculture
Publication 811: Agronomy Guide for Field Crops (2017, Ontario)
Ontario Ministry of Agriculture, Food and Agribusiness
2017 edition : product registrations have likely changed; verify current registrations
Weed Identification Guide for Ontario Crops (2026)
Ontario Ministry of Agriculture; University of Guelph authors
How a guide becomes searchable
Each guide is mapped, extracted, and indexed with the source details needed to trace an answer back.
Render the source
PDF pages become high-resolution images and text layers. The Ontario weed ID guide is collected directly from its HTML.
Map the document
Pages are classified by content type and grouped into crop chapters, reference sections, tables, and narrative.
Extract with context
Tables are read from page images while narrative uses the text layer. Guide, printed page, crop, and section stay attached.
Chunk and index
Clean excerpts are tagged with products, weeds, crops, tables, and pages, then embedded and loaded into a hybrid search index.
Technical notes on extraction
Most PDFs follow an automated classification and document-map workflow. The multi-state pilot uses a manually checked map, and Michigan's chapter PDFs share one logical page space.
Vision extraction handles dense tables. Narrative extraction cleans the text layer without adding facts. Ontario's weed ID HTML does not need vision extraction.
Each indexed chunk keeps its guide, printed page, table number, crop, products, and weeds so retrieval and citations use the same provenance.
What happens when you ask
The voice agent moves quickly, but the source and safety checks stay in the loop.
Understand the question
The recording becomes a transcript. Conversation history, crop names, products, weeds, and any stated region are resolved into one clear query.
Find the right excerpts
Meadowlark searches the guide for the selected region first. Any outside-region fallback is kept separate and clearly attributed.
Write, check, cite, and speak
An answer is drafted only from retrieved excerpts, checked for support, cited on screen, and then prepared for spoken playback.
Technical notes on the voice pipeline
Vector and keyword results are combined. Region coverage from the guide registry restricts search first, while thin results may be topped up with clearly attributed outside-region material.
Deterministic checks reject unsupported numbers, thresholds, product identities, citations, and drift between the spoken and on-screen answer. A separate verifier can approve or correct the draft.
Speech is generated only after the checked answer is ready. The recording is processed for transcription, and the conversation record is logged to improve reliability.
How we test it
A candidate answer strategy must clear accuracy gates with zero fabricated rates and zero source misattributions before it can replace the current strategy.
Regression questions
Known questions protect answer quality as the retrieval and response pipeline changes.
Multi-guide routing
Regional questions must use the right guide and identify any fallback without blending sources.
Provenance checks
Fact questions are pinned to an exact source chunk, page, and required source wording.
The label still comes first
Meadowlark never blends rates or restrictions across guides. If a regional guide is unavailable, the answer names any fallback source and asks you to verify locally. If the retrieved material cannot support an answer, Meadowlark withholds it.
Use Meadowlark to get oriented. Always read and follow the current product label before making an application.
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