TITLE    (click title to view slides)

Get the Most from Your POSTs

Dr. Eric P. Prostko
Extension Weed Specialist
University of Georgia
Tifton, GA

• Slide Presentation (PowerPoint, 1.7 MB)

TABLE OF CONTENTS

Get the Most from Your POSTs (Improving POST Herbicide Performance) POST Herbicide Performance Topic for Discussion: calibration Sprayer Calibration. Some Surveys said... Topic for Discussion: timing Postemergence Herbicide. Applications and Weed Size Optimum Timing of POST Applications A Few Exceptions to the Rule. Controlling Bigger Weeds Topic for Discussion: adjuvants Herbicide Adjuvants. Types Herbicide Adjuvants. What do they do?? The influence of additives on sicklepod control with Cadre - 68 DAT Herbicide Adjuvants Topic for Discussion: nozzle selection Nozzle Selection (contact or systemic herbicide?) Nozzle / Herbicide Chart Topic for Discussion: spray volume Spray Volume Topic for Discussion: antagonism Antagonism. What is it? Antagonism Problems in Peanuts Get the most from your Posts!

SLIDE CONTENTS

GET THE MOST FROM YOUR POSTS(Improving POST Herbicide Performance) Dr. Eric P. Prostko Extension Weed Specialist University of Georgia Tifton POST Herbicide Performance Environment X Application moisture temperature humidity calibration timing adjuvants nozzle selection spray volume antagonism Topic for Discussion calibration timing adjuvants nozzle selection spray volume antagonism Sprayer CalibrationSome Surveys said……… only 33% of operators were within 5% of target output (NE) 60% of the applicators were over or under applying pesticides by more than 10% (ND) Have you calibrated yours lately!!!! Topic for Discussion calibration timing adjuvants nozzle selection spray volume antagonism Postemergence Herbicide Applications and Weed Size smaller weeds easier to control lower rates can be used reduce competitive effects of weeds Timing is everything and size matters!!! Why??? Optimum Timing of POST Applications definitely probably No way!!! A Few Exceptions to the RuleControlling Bigger Weeds Delayed applications result in competition and yield loss !!!!!! Topic for Discussion calibration timing adjuvants nozzle selection spray volume antagonism Herbicide AdjuvantsTypes non-ionic surfactants (NIS) organosilicone surfactants crop oil concentrates (COC) fertilizers (N) buffers compatibility agents drift reduction agents stickers Herbicide AdjuvantsWhat do they do?? modify or maximize performance increase absorption and retention * decrease surface tension of water * prevent interaction with Ca, Na * increase permeability of cell membrane and cuticle The influence of additives on sicklepod control with Cadre - 68 DAT A. S. Culpepper, 1999 LSD 0.05 = 5 (MSO + OSS) (NIS) Herbicide Adjuvants read label COC > NIS avoid “miracle” products Topic for Discussion calibration timing adjuvants nozzle selection spray volume antagonism Nozzle Selection(contact or systemic herbicide?) contact * Gramoxone Max, Basagran, Blazer, Storm, Tough systemic * Cadre, Pursuit, Select, Poast, 2,4-DB, Classic PPT Slide Topic for Discussion calibration timing adjuvants nozzle selection spray volume antagonism Spray Volume contact or systemic contacts need better coverage i.e. more water contact herbicides need to be applied in at least 15 GPA systemic herbicides can be applied in 10 GPA but would prefer 15 GPA Topic for Discussion calibration timing adjuvants nozzle selection spray volume antagonism AntagonismWhat is it? interaction of 2 or more chemicals that results in a decrease in plant response. Antagonism Problems in Peanuts Broadleaf + grass herbicides * 2,4-DB + Poast or Select * 8-15% reduction in grass control 45% of time Herbicide + Fungicides * Select + chlorothalonil * Herbicides + Kocide or Mankocide Get the most from your Posts! Can’t do much about the weather but Can greatly influence application * calibration * timing * adjuvants * nozzle selection * spray volume * antagonism