Life Sciences Commons^™

Long-Term Effects Of April, August, Or October Prescribed Fire On Yearling Stocker Cattle Performance And Native Rangeland Plant Composition In The Kansas Flint Hills, Zachary M. Duncan, Alan J. Tajchman, Jack Lemmon, William R. Hollenbeck, Dale A. Blasi, K. C. Olson

Kansas Agricultural Experiment Station Research Reports

Objective:The objective of our experiment was to determine if prescribed fire applied in April, August, or October influenced stocker growth performance or plant community characteristics in the Kansas Flint Hills over a 6-year period.

Study Description:A total of 1,939 yearling stocker cattle were assigned to one of three prescribed-burn treatments: spring (April 11 ± 5.7 days), summer (August 25 ± 6.2 days or fall (October 2 ± 9.0 days) over a 5-year period. Calves were grazed from May to August for 90 days. Individual body weights were recorded at the start and end of the grazing season. Native …

Nutrient Management Strategies To Control Broomsedge Infestation And Improve Yield And Quality Of Tall Fescue Hayfields, Junior I. Yasuoka, Dale Helwig, Wendie Powell, Jaymelynn K. Farney, Gretchen F. Sassenrath, Bruno C. Pedreira

Kansas Agricultural Experiment Station Research Reports

A study in tall fescue hayfields infested with broomsedge and bluestem was conducted at four locations in southeast Kansas. The purpose of this study was to evaluate how phosphorus, nitrogen, and potassium fertilization affect yield, forage quality, and broomsedge/bluestem control in tall fescue hayfields. This trial will be repeated in 2023.

Weed Control With Imiflex In Igrowth Forage Sorghum, R. S. Currie, P. W. Geier, S. H. Lancaster, C. M. Weber

Kansas Agricultural Experiment Station Research Reports

Igrowth (imidazolinone-resistant) forage sorghum hybrids were recently commercialized in Kansas. Even though the active ingredient of the herbicide associated with these systems, imazamox, is used in other crops, data are needed to define best practices for use in forage sorghum. The objective of experiments in Manhattan and Garden City, KS, was to investigate the use of ImiFlex (imazamox) herbicide in Igrowth (imidazolinone-tolerant) forage sorghum. At Garden City, volunteer corn and johnsongrass control 29 days after treatment was 90% or greater in all treatments that included ImiFlex. Similarly, Palmer amaranth control 28 days after treatment was 91% or greater at Manhattan. …

Reviton And Vida With Tank Mixtures For Fallow Weed Control, Randall S. Currie, Patrick W. Geier

Kansas Agricultural Experiment Station Research Reports

In search of techniques to reduce irrigation water use in the Ogallala Aquifer region, several deficit irrigation techniques were evaluated in corn and cotton production. Several iterations of deficit irrigation (based on ET), including partial root-zone deficit (PRD) and regulated deficit irrigation (RDI) treatments, were implemented in the 2021 and 2022 summer season. Corn and cotton did respond to the different deficit irrigation treatments. Significant yield advantages were observed in fixed PRD on both crops while RDI also showed some yield advantage for corn.

Residual Herbicides As Single And Sequential Treatments For Efficacy In Corn, Randall S. Currie, Patrick W. Geier

Kansas Agricultural Experiment Station Research Reports

This research investigated the use of sequential applications of residual herbicides for the weed-free period in corn. The objective of the study was to compare residual herbicides as either preemergence (PRE) alone or split applications (PRE followed by postemergence). All treatments controlled Palmer amaranth, common lambsquarters, Russian thistle, and green foxtail 90% or more, and kochia 95% or more. Johnsongrass control early in the season was 91% or more regardless of treatment. However, no herbicide controlled johnsongrass as much as 80% late in the year.

Industrial Weed Control With Plainview Sc, Randall S. Currie, Patrick W. Geier

Kansas Agricultural Experiment Station Research Reports

The objective of this research was to determine application variable influence on Plainview SC (aminocyclopyrachlor/imazapyr/indaziflam) efficacy in an industrial setting. Plainview SC was applied at three rates and three application timings using two nozzle types to compare season-long weed control in noncropland. Late-season kochia control was best when Plainview SC was applied at 48 or 64 oz/a using flat-fan nozzles. Application timing did not affect these treatments. Similar control using the boomless nozzle required 64 oz/a of Plainview SC be applied either in fall or winter.

Residual Herbicides Alone And In Combinations For Fallow Weed Control, Randall S. Currie, Patrick W. Geier

Kansas Agricultural Experiment Station Research Reports

The objective of this research was to compare various novel herbicides for efficacy in fallow. An experiment compared residual herbicides for preemergence weed control in fallow. While most herbicides provided good kochia control early on, only the treatments containing Alite 27 (isoxaflutole) controlled kochia 90% or more by 50 days after treatment. Similarly, most herbicides controlled Russian thistle 83% or more early. However, Russian thistle control declined such that only the treatments containing Alite 27 provided as much as 74% control later in the season.

Allelopathic Potential Of Winter Wheat Varieties For Weed Suppression, C. Bott, A. Dille, A. Mohammad, L. Simão, L. O. Pradella, R. P. Lollato

Kansas Agricultural Experiment Station Research Reports

Summer weeds are an expensive economic and environmental problem during the fallow period following the harvest of a wheat crop. Anecdotal evidence suggests that different wheat varieties impact the need for weed control in the subsequent fallow period differently, with reasons ranging from residue amount and quality to the allelopathic potential of such residue. Thus, our objectives were to compare the allelopathic effects of different winter wheat varieties on weed and crop germination suppression. We collected the residue left after harvest of 25 varieties grown in a randomized complete block design in two Kansas locations (Hays and Great Bend) during …

Efficacy And Crop Response With Firstact In Accase-Tolerant Grain Sorghum, Randall S. Currie, Patrick W. Geier

Kansas Agricultural Experiment Station Research Reports

This research was conducted to determine the efficacy of quizalofop (FirstAct) herbicide in herbicide-tolerant grain sorghum. FirstAct herbicide was evaluated for efficacy and crop response in Double Team (ACCase-tolerant) sorghum. All herbicides controlled Palmer amaranth 90% or more and volunteer corn 95% or more late in the season. Johnsongrass control was 86 to 91%. Minor sorghum injury early in the season did not persist. Sorghum receiving FirstAct late postemergence yielded more grain than the nontreated control or sorghum receiving Parallel Plus preemergence.

Effect Of Corn Row Spacing On Herbicide Effectiveness For Weed Control In 2022, S. H. Lancaster, E. Adee

Kansas Agricultural Experiment Station Research Reports

Cultural weed control practices such as narrow row spacing can be a key component of successful weed management. Experiments were conducted in the Kansas River Valley to evaluate interactions of herbicide programs and corn row spacings on weed control and grain yield. There were no differences in weed control at a site with low weed density. However, at a site with high Palmer amaranth density, Resicore applied to 15- and 30-inch rows and Bicep + Acuron applied to 15-inch rows resulted in the greatest weed control. Corn yield was similar across all treatments at both locations.

Imiflex Evaluation At Two Kansas Locations In Igrowth Grain Sorghum, P. W. Geier, R. S. Currie, S. H. Lancaster, C. M. Weber

Kansas Agricultural Experiment Station Research Reports

Herbicide-tolerant grain sorghums, such as Igrowth (imidazolinone-resistant) hybrids were recently commercialized in Kansas. Even though the active ingredient of the herbicide associated with these systems, imazamox, is used in other crops, data are needed to define best practices for use in grain sorghum. The objective of these studies was to evaluate ImiFlex (imazamox) herbicide in Igrowth grain sorghum at two Kansas locations in 2022. ImiFlex applied postemergence provided 93% volunteer corn control, and 90 to 95% johnsongrass control regardless of application timing at Garden City. At Manhattan, ImiFlex controlled Palmer amaranth 90 to 99%. Early season grain sorghum injury was …

Effects Of Glyphosate Applied At Different Times On Dormant Zoysiagrass Cultivars In The Transition Zone, Dani Mcfadden, Jack D. Fry

Kansas Agricultural Experiment Station Research Reports

Winter annual weeds become a major problem during winter dormancy in warm-season turfgrass stands. In the transition zone, a winter glyphosate application is a common practice to reduce winter annual weed competition in zoysiagrass before emerging from dormancy in the spring. Research was conducted on the effects of glyphosate application timings on spring greenup and quality of experimental zoysiagrass genotypes compared to commercially available cultivars. Preliminary data from this study revealed a quicker spring greenup when glyphosate was applied in November compared to March. However, March-applied glyphosate significantly reduced cool-season weeds in experimental plots and enhanced quality compared to the …

Efficacy Of Impact Mixtures And Timings In Field Corn, Randall S. Currie, Patrick W. Geier

Kansas Agricultural Experiment Station Research Reports

The objective of this research was to determine the utility of topramezone (Impact) herbicide for efficacy in corn. An experiment evaluated Impact with various tank mix and premix partners at several application timings for weed control in corn. Most herbicides provided excellent control of Palmer amaranth, common lambsquarters, and green foxtail. When Impact alone was applied late postemergence (LPOST) following Dual II Magnum (metolachlor) applied preemergence (PRE), kochia and Russian thistle control was less than 85%. Herbicides applied early postemergence (EPOST) or postemergence (POST) provided the best johnsongrass control early in the season, but no treatments controlled johnsongrass more than …

Assure Ii Alone And With Tacoma And Classic For Efficacy In Fallow, R. S. Currie, P. W. Geier

Kansas Agricultural Experiment Station Research Reports

The objective of this trial was to compare Assure II (quizalofop) at two rates with or without tank mix partners for grass control in fallow. Assure II at either rate alone provided similar control of volunteer corn and barley. Corn control was 90% or more regardless of rating date with all herbicides except Assure II at 8.0 oz/a plus Classic (chlorimuron) at 42 days after treatment (DAT). Tacoma (fenoxaprop) at 3.5 or 5.4 oz/a added to Assure II at 8.0 oz/a improved barley control later in the season.

Pyraflufen Tank Mixtures For Efficacy In Fallow, R. S. Currie, P. W. Geier

Kansas Agricultural Experiment Station Research Reports

The objective of this study was to compare Vida (pyraflufen) tank mixtures for glyphosate- resistant kochia control in fallow. Early-season kochia control was best with tank mixtures that included Sharpen (saflufenacil), but tank mixtures including dicamba provided the best control later in the season. No herbicide controlled kochia more than 80% late in the season. All herbicides controlled downy brome more than 90% within 14 days after treatment, and 100% by 21 days after application.

Roundup 2022: Agricultural Research Center-Hays

Kansas Agricultural Experiment Station Research Reports

Roundup is the major beef cattle education and outreach event sponsored by the Kansas State University Agricultural Research Center - Hays. This report communicates timely, applicable research information on beef production and rangeland topics.

Fall-Planted Cover Crops For Weed Suppression In Western Kansas, S. Dhanda, V. Kumar, A. K. Obour, A. Dille, J. D. Holman

Kansas Agricultural Experiment Station Research Reports

The widespread evolution of herbicide-resistant (HR) kochia and Palmer amaranth warrants the use of alternative ecological-based strategies for weed management in no-tillage (NT) dryland cropping systems in western Kansas. A field study was established in the fall of 2020 at Kansas State University Agricultural Research Center near Hays, KS, to determine the impact of fall-planted cover crop (CC) mixture on 1) kochia and Palmer amaranth suppression (density and biomass reduction), and 2) Palmer amaranth emergence dynamics in subsequent grain sorghum. A CC mixture of winter triticale, winter pea, radish, and rapeseed was planted in wheat stubble in the fall of …

Vegetation And Animal Production In Pastures Sprayed For Western Ragweed Control, Keith Harmoney, John Jaeger

Kansas Agricultural Experiment Station Research Reports

Western ragweed (Ambrosia psilostachya) is a common native forb found throughout Kansas native rangelands and in some seeded pastures. Over time, western ragweed can form dense colonies from growth of lateral creeping rootstalks with multiple buds that can initiate new growth and form an upright stem and plant. Past research has shown that western ragweed does not compete with native grass production until ragweed contributes over approximately 35% of the forage dry matter of a pasture area. Cattle have utilized western ragweed in past long-term historical grazing trials. In a previous long-term trial at Hays, KS, western ragweed …

Herbicide Activity On Old World Bluestems, Keith Harmoney

Kansas Agricultural Experiment Station Research Reports

Two main species of old world bluestems (OWB), yellow bluestem (Bothriochloa ischaemum) and Caucasian bluestem (Bothriochloa bladhii), have encroached on rangelands, pastures, and road right-of-ways in Kansas. Patches of these OWB have been shown to reduce species diversity and abundance at multiple trophic levels, and pose a long-term threat to native plant, insect, rodent, and grassland bird populations. These OWB species are utilized by cattle early in the growing season, directly following prescribed burns, and during droughts when other forages lack water uptake and may go dormant. However, these OWB species mature more quickly than native …

Confirmation And Control Of Imazamox-Resistant Shattercane, V. Kumar, R. Liu, T. L. Lambert, R. Perumal, B. Bean

Kansas Agricultural Experiment Station Research Reports

Shattercane is a summer annual grass weed species commonly found in grain sorghum producing regions, including Kansas. Recent development and commercialization of grain sorghum hybrids with tolerance to acetolactate synthase (ALS) and acetyl-CoA-carboxylase (ACCase) inhibiting herbicides will allow producers to use these herbicides for in-season control of shattercane. In a recent field survey, three shattercane populations (DC8, GH4, and PL8) collected from sorghum fields in northwestern Kansas survived the field-use rate (6 fl oz/a) of postemergence (POST) applied IMIFLEX (imazamox). The main objectives of this research were to (1) confirm and characterize the level of resistance to imazamox in those …

Industrial Weed Control With Plainview, Esplanade, And Method Application Timings, R. S. Currie, P. W. Geier

Kansas Agricultural Experiment Station Research Reports

The objective of this trial was to compare Plainview, Esplanade, and Method at three applications for season-long weed control in noncropland. Glyphosate alone provided no residual weed control. Plainview (indaziflam/aminocyclopyrachlor/imazapyr) at 64 oz/a applied in the early or late fall controlled kochia similarly to Krovar (bromacil/ diuron) late in the season. Either rate of Plainview, as well as the tank mixture of Esplanade (aminocyclopyrachlor) plus Method (indaziflam), provided complete woollyleaf bursage control regardless of application timing. No treatment of Krovar controlled woollyleaf bursage more than 60%.

Imiflex Rates For Efficacy In Imidazolinone-Tolerant Grain Sorghum, R. S. Currie, P. W. Geier

Kansas Agricultural Experiment Station Research Reports

The objective of this study was to compare ImiFlex rates and timings for efficacy and crop response in imidazolinone-tolerant grain sorghum. Volunteer corn and Johnsongrass control was generally best when ImiFlex (imazamox) was applied postemergence (POST), except when tank mixed with Huskie (bromoxynil/pyrasulfotole). Likewise, Palmer amaranth control was most consistent when ImiFlex was applied POST. Though all herbicides increased grain yields relative to the weedy controls, yields increased the most when Moccasin II Plus (metolachlor) plus Motif (mesotrione) preemergence (PRE) was followed by ImiFlex POST or Moccasin II Plus and Sharpen (saflufenacil) PRE was followed by ImiFlex plus atrazine POST.

Katagon At Two Timings Compared To Standards In Corn, R. S. Currie, P. W. Geier

Kansas Agricultural Experiment Station Research Reports

The objective of this trial was to compare Katagon (tolpyralate/nicosulfuron) to standard treatments for weed control in corn. Katagon plus atrazine applied early postemergence was as effective as any herbicide tested on the weeds present. When application timing was delayed to late postemergence, most herbicides were less effective. Early season corn injury was minor and did not persist. Although most herbicide treatments increased yields relative to the non-treated control, yields were generally best when any treatment was applied early postemergence.

Firstact For Efficacy In Accase-Tolerant Grain Sorghum, R. S. Currie, P. W. Geier

Kansas Agricultural Experiment Station Research Reports

The objective of this study was to compare FirstAct with several tank mix partners for efficacy in herbicide-tolerant grain sorghum. FirstAct (quizalofop) alone or in tank mixtures controlled Johnsongrass 94% or more. However, tank mixing FirstAct with any broadleaf herbicide was generally antagonistic to Palmer amaranth control. Minor sorghum injury was 5% or less by four weeks after postemergence treatment. Sorghum yields increased with all postemergence treatments except with atrazine alone.

Single And Split Herbicide Applications For Efficacy In Corn, R. S. Currie, P. W. Geier

Kansas Agricultural Experiment Station Research Reports

The objective of this study was to compare season-long weed control from single and sequential herbicide applications in corn. Control of all weed species was generally good (90% or more) early in the season regardless of preemergence (PRE) herbicide. However, Russian thistle and Palmer amaranth control was best later in the season when a PRE herbicide was followed by a postemergence (POST) treatment. While all herbicide treatments increased yields compared to the untreated control, yields were greatest when Lumax EZ PRE (atrazine/mesotrione/metolachlor) was followed by Acuron (atrazine/bicyclopyrone/mesotrione/metolachlor) and glyphosate POST.

Reclaiming Old World Bluestem Pasture With Imazapyr Application And Native Grass Overseeding, Keith Harmoney

Kansas Agricultural Experiment Station Research Reports

Old world bluestems (OWB), mainly Caucasian bluestem (Bothriochloa bladhii) and yellow bluestem(Bothriochloa ischaemum)introduced from parts of eastern Europe, Asia, Africa, and Australia, have been shown to reduce abundance and diversity of some insect and wildlife species compared to native grasses when these OWB grasses form dense stands. These OWBs have been invading native pastures in the southern Great Plains and are rapidly increasing in the amount of area occupied in Kansas. Two landowners purchased pasture property in Ellsworth County, KS, and observed that Caucasian old world bluestem had increased in the pasture significantly over the course …

Response Of Conventional Sorghum To Imiflex, Zest Wdg, And Firstact, R. Liu, V. Kumar, M. Marrs, T. L. Lambert

Kansas Agricultural Experiment Station Research Reports

Grass weed control in sorghum has been a serious challenge for sorghum growers. The newly developed herbicide-tolerant (HT) sorghum technologies such as igrowth, Inzen, and Double Team sorghum will allow growers to use IMIFLEX, ZestWDG, and FirstAct respectively, for in-season weed control. However, the adoption of these HT sorghum technologies may increase the use of these labeled herbicides and increase the likelihood of herbicide drift or tank contamination to conventional sorghum. Three separate field studies were conducted at Kansas State University Agricultural Research Center (KSU-ARCH) near Hays, KS, to understand the response of conventional sorghum to various rates of IMIFLEX, …

Glyphosate-Resistant Palmer Amaranth Control In Xtendflex Soybean, R. Liu, V. Kumar, T. L. Lambert

Kansas Agricultural Experiment Station Research Reports

XtendFlex soybean is a triple-stacked trait technology that allows growers to use dicamba (XtendiMax) and glufosinate (Liberty) for in-season control of glyphosate-resistant (GR) weed species, including Palmer amaranth. A field study was conducted at the Kansas State University Agricultural Research Center (KSU-ARCH) near Hays, KS, to determine the effectiveness of POST applied XtendiMax and Liberty alone or in sequential applications for GR Palmer amaranth control in XtendFlex soybean. The study site had a natural infestation of GR Palmer amaranth. Results showed that early post-emergence (EPOST) applications of XtendiMax or Liberty followed by (fb) a late post-emergence (LPOST) application …

Fallow Weed Control With Vida Tank Mixtures, R. S. Currie, P. W. Geier

Kansas Agricultural Experiment Station Research Reports

The objective of the study was to compare Vida (pyraflufen) with various tank mix partners for glyphosate-resistant kochia control. Flixweed control was complete in fallow with all herbicides by 28 days after treatment. Kochia control was best when Vida was applied with glyphosate and Spartan. However, due in part to the extremely dry conditions, no treatment controlled kochia by more than 83% at 28 days after treatment, and kochia control began to decline after this 28 DAT.

Zest Application Timings For Efficacy In Grain Sorghum, R. S. Currie, P. W. Geier

Kansas Agricultural Experiment Station Research Reports

This study was conducted to compare Zest (nicosulfuron) herbicide at two rates and two application timings for efficacy in grain sorghum. Palmer amaranth control was best when a preemergence (PRE) herbicide was followed by a late postemergence (LPOST) treatment. Zest at 0.67 or 1.33 oz/a provided the best velvetleaf and shattercane control. Either rate of Zest applied early postemergence (EPOST) controlled green foxtail more than 90%, but the higher rate was required for greater than 90% control when applications were delayed until LPOST.