Oklahoma Broomsedge Bluestem Pasture Reclamation Research
Applied Research
Jennifer Patterson
Ext Ed Ag/4H
Stilwell
Abstract
Broomsedge Bluestem (Andropogon virginicus) is an opportunistic-indicator plant, colonizing areas where inherent soil nutrients or grazing management are less than ideal for desirable forages, such as Bermudagrass. OSU research has proven that Broomsedge can flourish in soils low in Phosphorus (P) and acidic soils low in pH. Nevertheless, in Eastern Oklahoma recent reports have indicated Broomsedge dominating properly managed pastureland with adequate pH and Phosphorus levels. Some reports have indicated Broomsedge infestations reaching 25-50% ground cover within the last few years. It is believed that stressful environmental conditions, and the resultant weakened stands of desirable forages over the last 12 years has caused this increase in Broomsedge populations. Traditional Broomsedge control recommendations involved correcting soil nutrient deficiencies, improving grazing management, and time. With this unexpected Broomsedge increase in properly managed areas, local producers needed a control method with a quicker turnaround. Through an OSU Extension working partnership with a local Adair County OK livestock producer, a field research trial was established in 2022. The study was flagged as 10 ft x 20 ft plots arranged in a randomized complete block design. Fertilizer, lime and herbicide treatments were applied on July 14, 2022. Visual control ratings were assessed at 35 and 70 days after treatment (DAT), and plots were also evaluated at 10 months after treatment (MAT) to determine Broomsedge population reduction and forage recovery. Results showed the most significant reduction in Broomsedge population occurred with the application of 12oz glyphosate. The addition of required N, P, K, and lime to this herbicide rate elicited a fast response from the Bermudagrass and other desirable forages, aiding in stand recovery and further competing against surviving Broomsedge plants. This study illustrates that in severe Broomsedge infestations (over 50%) or if immediate forage recovery is warranted, an application of glyphosate at 12oz/acre proved effective with minimal injury to Bermudagrass. Correcting nutrient deficiencies and utilizing sound grazing practices are still the first step to improve desired forages. Results from this study were shared at the annual Adair County Pasture Tour, Cattlemen’s Association programs, as well as across the state with other Educators and Specialists.
Poster has NOT been presented at any previous NACAA AM/PIC
This poster is being submitted for judging. It will be displayed at the AM/PIC if not selected as a State winner. The abstract will be published in the proceedings.
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Authors: Jennifer Patterson, Brian Pugh
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Patterson, J. Ext Ed Ag/4H, Oklahoma State University , Oklahoma, 74960
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Pugh, B. OSU Extension Area Agronomy Specialist, Oklahoma State University , Oklahoma, 74401