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# GTBOP Processing Log: Weed Control in Ornamentals — Dr. Chris Marble

## Conversation Snapshot — February 27, 2026

## Webinar Details

Field | Details
--- | ---
Title | Weed Control in Ornamentals for the Nursery and Landscape
Speaker | Dr. Chris Marble, Associate Professor, Ornamental and Landscape Invasive Weed Management, Mid-Florida Research and Education Center, University of Florida
Moderator | Dr. Shimat Joseph, UGA Turfgrass Entomologist
Webinar Date | July 13, 2023
Series | Green & Commercial
Duration | 50:38
Topic Area | Weed Science
CEU Categories | 10 (Private), 21, 23, 24, 27, 31, 32, 35

## Pipeline Stages Completed

All five standard archive stages were completed in a single session:

Stage | Deliverable | Filename
--- | --- | ---
1 | Corrected SRT | `GTBOP_Transcript_2023-07-13_WeedControlOrnamentals.srt`
1 | Correction Summary | `GTBOP_Corrections_2023-07-13_WeedControlOrnamentals.md`
2 | Archive Package | `GTBOP_Archive_Summary_2023-07-13_WeedControlOrnamentals.md`
3 | YouTube Description | `GTBOP_YouTube_2023-07-13_WeedControlOrnamentals.md`
3 | Website Version | `GTBOP_Website_2023-07-13_WeedControlOrnamentals.md`
3 | Extension Agent Version | `GTBOP_ExtAgent_2023-07-13_WeedControlOrnamentals.md`
4 | Moodle Quiz | `GTBOP_Quiz_2023-07-13_WeedControlOrnamentals.md`
4 | Moodle Matching | `GTBOP_Matching_2023-07-13_WeedControlOrnamentals.md`
5 | Prose Transcript | `GTBOP_ProseTranscript_2023-07-13_WeedControlOrnamentals.md`

Stage 6 (Collaborative Writing Resources) was not requested for this webinar.

## Stage 1: Transcript Correction — What Happened

### Source File

- Input: `Weed_Control_in_Ornamentals_for_the_Nursery_and_Landscape_with_Dr__Chris_Marble.srt`
- 618 subtitle blocks, 2,473 lines, read in full across 6 sequential chunks before any processing began

### Transcript Quality

This was an unusually correction-heavy transcript. Whisper struggled significantly with weed science terminology, producing ~80 individual corrections across 65+ blocks. Two systematic errors dominated:

1. "Herbicides" rendered 7+ different ways (~15 occurrences) Whisper could not capture the word "herbicides" and produced: "cervicides," "service sites," "surface sites," "service side," "service size," "services," and "pelvies sites." All were corrected to "herbicides" in context.

2. "Weed species/spectrum" rendered as "wheat" (6 occurrences) Whisper consistently heard "wheat" instead of "weed" — corrected throughout.

### Other Major Correction Categories

- Speaker name: "Mahabou" → "Marble" (Whisper garbled the speaker's surname)
- Institution: "Mid-Florida Church and Education Center" → "Mid-Florida Research and Education Center"
- Product names: Heavy corrections needed — Specticle, SureGuard, Gallery, isoxaben, Finale, Fusilade, Basagran, Lontrel, Pennant Magnum, Axxe, Finalsan, FireWorxx, and many active ingredients (flumioxazin, indaziflam, clopyralid, sethoxydim, clethodim, fluazifop, fenoxaprop, acetic acid)
- Technical terms: "woody one of mills" → "woody ornamentals," "annual brograss" → "annual bluegrass," "gramaticides" → "graminicides," "mongongrass" → "mondo grass," etc.

### Audio Verification Round

Nine items were flagged `[VERIFY]` in the initial corrected SRT for audio confirmation. Rich checked all nine against the recording and provided resolutions:

Block | Flagged Item | Resolution
--- | --- | ---
79 | "mills in the landscape" | Corrected → "ornamentals in the landscape"
117 | "especially broadly, ornamental plants" | Confirmed as transcribed
189 | "your men's and weeds" | Corrected → "you're managing weeds"
472 | "Fireworks" | Corrected → "FireWorxx"
525 | "Segment" | Confirmed as transcribed
555 | "plan outs" (initially corrected to "plant apps") | Confirmed as "plan outs" — reverted
592 | "not when wind speeds are below 5 mph" | Confirmed as transcribed
612 | Repeated "Marengo" | Corrected → "SureGuard"
613 | "Tau" (initially corrected to "Tower") | Confirmed as "Tower"

After resolutions, zero VERIFY flags remain in the final corrected SRT.

### New Speaker for Reference Roster

Dr. Chris Marble is not in the existing GTBOP speaker reference. Recommended addition:

Name | Affiliation
--- | ---
Dr. Chris Marble | Associate Professor, Ornamental and Landscape Invasive Weed Management, Mid-Florida Research and Education Center, University of Florida

### New Correction Patterns

This transcript surfaced numerous product names not previously in the Common Corrections Reference. The correction summary includes a table of 14+ new Whisper-to-correct patterns for future use, including: cervicides → herbicides, Fireworks → FireWorxx, Axe → Axxe, Final Sand → Finalsan, acidic acid → acetic acid, gramaticides → graminicides, Pusillate → Fusilade, Basagram/Bacagrand → Basagran, Long Trail/Lontrell → Lontrel, clopyrrolid → clopyralid, Phenal → Finale, Pindemagnum → Pennant Magnum, Dazzaplam → indaziflam.

### Verification

- Block count: 618 original = 618 corrected ✓
- All 1,236 timestamps preserved exactly ✓
- No blocks merged or split ✓

## Stage 2: Archive Package — What Was Produced

The archive package contains three sections, all derived exclusively from the corrected transcript:

### Narrative Summary

- 385 words, flowing paragraphs, no bullet points
- Covers the full presentation arc: calibration fundamentals → pre/post-emergence timing → three-step herbicide selection → pre+post research results → glyphosate alternatives → selective herbicides → resources/Q&A
- Every topic traceable to specific transcript content

### YouTube Timestamps

- 38 chapter markers covering the full 50:38 duration
- First timestamp: `0:00` ✓
- Last timestamp: `49:08` (within 1:30 of end) ✓
- Density note: 38 entries across ~51 minutes is denser than the typical 3–5 minute interval. This presentation had unusually frequent topic transitions — Marble moved through substantial material quickly. The density reflects genuine content shifts, not over-segmentation.

### Questions & Answers

- 11 Q&A pairs (within the 8–12 target range)
- Mix of recall, application, and identification questions
- All answers derived directly from presentation content — no external information
- Covers calibration, timing, the three-step process, rotation importance, pre+post research, glyphosate alternatives, desiccant performance, selective options, signal words, and drift reduction

## Stage 3: Platform Optimization — Three Versions

### YouTube Description

- 4,914 characters (within ~5,000 limit)
- Condensed single-paragraph summary
- All 38 timestamps retained
- Q&A condensed to 4 highest-value pairs
- Hashtags included

### Website Version

- Full archive package from Stage 2
- Formatted for web publication with complete Q&A and resource links

### Extension Agent Version

- CEU category table prominently displayed with all 8 applicable categories
- Asynchronous viewing instructions for county agent CEU delivery
- Condensed content summary with a "Key Topics for CEU Relevance" section connecting material to license categories
- Full chapter list for video navigation

## Stage 4: Moodle Activities — Quiz and Matching

### Quiz

- 15 multiple choice questions with answer keys
- Difficulty distribution: 53% Recall / 33% Application / 13% Analysis
- Coverage spans early (Q1–7: calibration, timing, environmental factors), middle (Q8–11: rotation, three-step selection, research), and late (Q12–15: alternatives, graminicides, signal words) portions of the presentation
- Every question includes timestamp references and transcript source citations
- No "all of the above" / "none of the above" options
- All distractors drawn from plausible but incorrect interpretations of presentation content

### Matching Exercises

Three exercises, each with distractors to prevent elimination guessing:

Exercise | Type | Pairs | Distractors
--- | --- | --- | ---
1: Post-Emergence Products & Characteristics | Product-Characteristic | 7 | 2
2: Pre-Emergence Mode of Action Groups | Product-Category | 6 | 1
3: Weed Management Timing & Practice | Timing-Practice | 8 | 2

## Stage 5: Prose Transcript — Full Conversion

The corrected SRT was converted into a readable markdown document preserving all 618 blocks of content in flowing prose.

### Structure

- ~9,300 words
- 14 H2 major sections aligned to genuine topic transitions
- 24 H3 subsections for distinct subtopics
- 24 speaker labels at every change of speaker (17 Marble, 7 Joseph)
- 9 italicized active ingredient names on first mention
- Source attribution footer with filename and block count

### Section Architecture

The H2/H3 structure follows Dr. Marble's own presentation flow:

1. Introduction
2. Why Herbicides Fail: Calibration and Application
3. Pre-emergent Herbicide Timing
4. Post-emergence Herbicide Timing
5. Importance of Developing a Program, Not Just Products
6. Three Steps to Choosing Herbicides
7. Year-Round Nursery Rotation Plan
8. Research: Pre-emergent + Post-emergent vs. Post-Only Programs
9. Application Interval Considerations
10. Landscape-Specific Rotation Planning
11. Post-emergence Alternatives to Glyphosate in Landscape Beds
12. Selective Post-emergence Options for Landscape Beds
13. UF Mid-Florida REC Resources and Contact Information
14. Questions and Answers (with H3 subheaders for each Q&A topic)

## Presentation Content Overview

For team members unfamiliar with this webinar, here's what Dr. Marble covered:

Dr. Marble presented a comprehensive, practical guide to building herbicide programs for ornamental nursery production and landscape maintenance. He began with calibration — identifying it as the #1 cause of herbicide failure and sharing free UF-developed calculators. He then covered herbicide timing for both pre-emergent (apply after soil settles, avoid tender new growth, reapply every 8–12 weeks in nurseries vs. 2–3 times/year in landscapes) and post-emergence applications (treat small, actively growing weeds; morning applications on clear days perform best).

The core of the presentation was a three-step herbicide selection process: (1) determine what's labeled/safe for the ornamental, (2) identify primary and secondary weed species by season, and (3) combine into a year-round rotation using different modes of action. He walked through this using container-grown gardenia as an example, referencing the 2017 Southeast Pest Control Guide (compiled by Marble, Jeff Derr, and Joe Neal) for efficacy and safety ratings.

He presented research showing that combining pre-emergent with post-emergence herbicides reduced total herbicide active ingredient by 40–60% and costs by up to 30% versus post-only programs. He reviewed glyphosate alternatives (glufosinate, desiccant-type products like Axxe, Finalsan, FireWorxx) and highlighted underutilized selective herbicides — particularly graminicides (Segment, Envoy, Fusilade, Acclaim) that can be applied over the top of hundreds of broadleaf ornamentals.

The Q&A covered signal words/PPE requirements, drift reduction strategies, and Marengo use in nursery gravel areas.

## Notes for Team

- New speaker: Dr. Chris Marble should be added to the reference roster for future processing
- New correction patterns: 14+ new Whisper error patterns documented in the correction summary — useful for future weed science transcripts
- Broad CEU applicability: This session carries 8 CEU categories, making it a strong candidate for cross-disciplinary certificate courses
- Stage 6 not completed: No publication project was identified for this webinar. The prose transcript is available if collaborative writing resources are needed later

Processing completed February 27, 2026 Pipeline: Stages 1–5 (standard archive + prose transcript) Project: GTBOP Webinar Archive Processing (v4.0 instructions)