UPDATE: Applying Pre-Emergent Herbicides on Sports Turf
Spring is just around the corner and with spring comes the arrival of crabgrass control applications. The use of crabgrass pre-emergent herbicides on sports turf must be carefully considered. Will I need to overseed in the spring? Will I need to overseed the entire field or just certain areas? Is the option to overseed more important than crabgrass pressure later in the summer? All good questions, let’s work to an answer.
HOW DO THE PRODUCTS WORK?
First of all, let’s take a look at how crabgrass pre-emergent products work.
Research has shown that applications should be made when average daily soil temperatures reach 57 to 64 degrees at a 1 inch depth. Following application, a barrier will form that will inhibit crabgrass seedling emergence.
Keep in mind, the barrier will also inhibit grass seed emergence! How do you know when you should apply if you do not want to check daily soil temperatures? Simply go to the Growing Degree Day Tracker. (GDD Tracker) The tracker is a joint effort from Michigan State Turfgrass, Purdue Turfgrass and the Midwest Regional Turf Foundation (MRTF). The GDD Tracker will provide updates on when the product needs to be applied. Typically, pre-emergent products need to be applied prior to April 1 in the southern third of the state of Indiana, by April 15 in the middle third, and by April 30 in the northern third.
WHAT ARE THE BEST PRE-EMERGENT OPTIONS?
So, the plan is to apply a crabgrass pre-emergent herbicide product. The timing has been determined. Now the question is, “What product should I apply?”
To keep it simple consider two products: 1. Dithiopyr (Dimension) 2. Prodiamine (Barricade)
Advanced Turf Solutions offers both products. Please call for options as the products are available in both granular and liquid formulations.
I MISSED MY APPLICATION. CAN POST-EMERGENT APPLICATIONS BE MADE?
Yes. Careful consideration should be made to select the best products as some pre-emergent products (Prodiamine) will not be effective. My recommendation for early season (April through early May) is Dithiopyr as the product is effective on crabgrass in the one to three leaf stage. Liquid applications are recommended.
TIP – If dormant seeding was used on the playing surface, a late spring application of Dithiopyr (after the turfgrass seed has germinated) will control young crabgrass while also creating a barrier for any crabgrass seed that has not germinated. Other post-emergent products include Fenoxyprop and Quinclorac (Quin Pro). As always, please check product labels for rates.
TIPS TO REDUCE CRABGRASS PRESSURE:
Maintain a dense turf stand
Irrigate turfgrass with deep and infrequent cycles
More than half of your total nitrogen should be applied from September through November
When possible, water in pre-emergent products
THINGS TO CONSIDER BEFORE A PRE-EMERGENT HERBICIDE APPLICATION:
Do I need to overseed?
Should I avoid high traffic areas where I know I will be overseeding?
Co-founder and partner of J&D Turf. A sportsturf junkie, I cut my teeth at Victory Field with the Indianapolis Indians maintaining the playing surface at what has been dubbed "The Best Minor League Ballpark in America." From intern, to assistant to head groundskeeper over 10 seasons, I was director of operations for the team before realizing sportsturf was my passion, baseball was merely the game.
My bachelor’s degree in sports management from Marian University and a degree in turfgrass science from Purdue University serve as the initial credibility with clients ranging from university to K-12 administrators, parks and rec officials, and maintenance crews to my friends with their own fields in the Major Leagues.
The "Smart Turf" blog is my way of sharing my experiences as consultant, groundskeeper and business owner with the larger sportsturf community. There was a day early in my career that I'd joke that I live to make tall grass short. Given the expanding horizon of this profession over the last decade, I've come to realize and respect it as much more.