Life Sciences Commons^™

Fallow Weed Control With Preemergence Applications Of Balance Pro, Corvus, Banvel, Atrazine, And Authority Mtz, R. Currie, P. Geier

Kansas Agricultural Experiment Station Research Reports

Atrazine alone applied in the fall was less effective for kochia and Russian thistle control than other fall- or spring-applied herbicides in early summer. In mid season, control of kochia and Russian thistle was 85% or less with all fall-applied herbicides. Banvel (dicamba) increased kochia control when added to Balance Pro (isoxaflutole), plus Autumn Super (iodosulfuron + thiencarbazone), plus atrazine applied in the spring at mid season. All other spring herbicides were similar for kochia control. Russian thistle control was similar among all spring-applied herbicides except atrazine plus Banvel.

Effects Of Intensive Late-Season Sheep Grazing Following Early-Season Steer Grazing On Population Dynamics Of Sericea Lespedeza In The Kansas Flint Hills, J. Lemmon, W. H. Fick, J. A. Alexander, G. W. Preedy, C. A. Gurule, K C. Olson

Kansas Agricultural Experiment Station Research Reports

Sericea lespedeza (Lespedeza cuneata; SL) is a high-tannin, invasive forb in the Tallgrass Prairie ecosystem. In Kansas, sericea lespedeza infests 980 square miles of pasture, primarily in the Flint Hills region. Sericea lespedeza infestations reduce native grass production by up to 92% through a combination of aggressive growth, prolific reproduction, canopy dominance, and chemical inhibition (allelopathy). Herbicides retard the spread of sericea lespedeza, but application is laborious and expensive; moreover, herbicides are lethal to ecologically-important, non-target plant species.

Increased grazing pressure on sericea lespedeza by domestic herbivores may slow its spread and facilitate some measure of biological control. …

Fallow Weed Control With Postemergence Applications Of Agh15004, Ag14039, Roundup Powermax, And Atrazine, R. Currie, P. Geier

Kansas Agricultural Experiment Station Research Reports

All treatments except AGH15004 at 1.5 pt/a plus Roundup PowerMax (glyphosate) and nonionic surfactant provided more than 95% kochia control at 14 days after treatment (DAT). By 28 DAT, only those treatments containing atrazine provided greater than 95% kochia control. However, kochia control at 42 DAT was greater than 90% with all treatments except Roundup PowerMax plus nonionic surfactant.

Effects Of Growing-Season Prescribed Burning On Vigor Of The Noxious Weed Sericea Lespedeza (Lespedeza Cuneata) In The Kansas Flint Hills, J. A. Alexander, W. H. Fick, J. Lemmon, C. A. Gurule, G. W. Preedy, K C. Olson

Kansas Agricultural Experiment Station Research Reports

Sericea lespedeza (SL) was introduced into the United States from Asia in the late 19th century. Early land managers recognized that SL was adaptable; tolerant of shallow, acidic or low-fertility soils; and resistant to insects and disease. This combination of traits made SL a widely-used plant for reseeding strip-mined lands, highway right-ofways, dams, and waterways in the US for nearly a century.

Regrettably, SL is highly fecund. Individual plants are capable of producing up to 850 lb of seed per acre annually. Vigorous seed production allows SL to rapidly infiltrate native grasslands that are adjacent to reseeding projects; seed can …

Old World Bluestem Seedling Emergence And Vegetative Cover Following Glyphosate Treatment, K. R. Harmoney

Kansas Agricultural Experiment Station Research Reports

Old world bluestems (OWB) are perennial warm-season grasses introduced into the U.S. from parts of Asia, eastern Europe, Africa, and Australia. The two most common old world bluestem species found in Kansas are yellow bluestem (Bothriochloa ischaemum), otherwise known as King Ranch bluestem, and Caucasian bluestem (Bothriochloa bladhii). These grasses were introduced for soil conservation and forage production in arid regions of the southern Great Plains; however, in Kansas and elsewhere, they have escaped areas where planted and have been invading native rangelands and pastures that were old crop fields seeded back to native grasses. Efforts …

Ropewick Application To Control Old World Bluestems, K. R. Harmoney

Kansas Agricultural Experiment Station Research Reports

Old world bluestems (OWB) were introduced into the United States in the early 1900s for conservation and forage purposes. The two main OWB species found throughout the southern Great Plains are Caucasian bluestem (Bothriochloa bladhii) and yellow or King Ranch bluestem (Bothriochloa ischaemum). These introduced OWB grasses are warm-season grasses with excellent persistence and production characteristics for regions with low rainfall. These grasses also produce abundant seed and establish more easily under arid conditions compared to some of our most common native warm-season grasses of the Great Plains. The characteristics that enable OWB to be well …

Control Of Individual Honey Locust Trees In Grazed Pasture, K. R. Harmoney

Kansas Agricultural Experiment Station Research Reports

Honey locust (Gleditsia triacanthos) is a deciduous tree that produces large brown seed pods and thorny appendages, and is present throughout most of the US. The pods are highly nutritious for livestock and wildlife, and are easily spread by animals in dung pats. Honey locust is typically found in greatest concentrations in the central U.S. in the same general range as historical tallgrass prairie. Fire suppression and introduction of honey locust into shelter belts has allowed honey locust to increase into more arid regions associated with mixed grass prairie. When cut, honey locust is capable of producing abundant …

Influence Of Glyphosate Timings On Conversion Of Golf Course Rough From Tall Fescue To ‘Sharps Improved Ii’ Buffalograss, J. Reeves, J. Hoyle, D. Bremer, S. Keeley

Kansas Agricultural Experiment Station Research Reports

All treatments, except the control that received no glyphosate application, resulted in acceptable buffalograss establishment (>90% buffalograss green cover) by 70 days after seeding (DAS). However, any treatment not sprayed prior to seeding date or that received a 7 DAS application lagged behind in establishment for 6 weeks after seeding.

Late Pre-Emergent Control Of Annual Bluegrass With Flazasulfuron & Indaziflam, J. Reeves, J. Hoyle

Kansas Agricultural Experiment Station Research Reports

All applications of flazasulfuron or indaziflam resulted in acceptable control of Annual Bluegrass (Poa annua), only allowing<3% visual weed cover (VWC) in all treatments compared to the non-treated (26% VWC) up to 133 days after application (DAA).

Fallow Weed Control With Preemergence Applications Of Clarity, Atrazine, Spartan Guard, Sharpen, Zidua, And Corvus, R. Currie, P. Geier

Kansas Agricultural Experiment Station Research Reports

Kochia control at 8 weeks after spring application (WAST) was greatest when Clar­ity (dicamba) was included in the spring applications or when Corvus (isoxaflutole + thiencarbazone) was applied with atrazine and Clarity in the fall. The best kochia con­trol at 13 WAST occurred with spring applications containing Clarity. Only Clarity plus Atrazine, Sharpen, Zidua, Spartan Guard, or Corvus applied in the spring provided as much as 90% kochia control at 20 WAST. Only the spring application of Spartan Guard and Clarity controlled Russian thistle 90% at 20 WAST.

Alion, Sencor, And Sharpen For Preemergence Kochia Control In An Abandoned Alfalfa Field, R. Currie, P. Geier

Kansas Agricultural Experiment Station Research Reports

Alion (indaziflam) combined with Sencor (metribuzin) were the most effective herbi­cides for kochia control. Sharpen (saflufenacil) alone or with Prowl H2O (pendimeth­alin), Sencor, or Alion was less effective at controlling kochia compared to Alion plus Sencor. By 91 days after treatment (DAT), Alion at rates above 3 oz/a plus Sencor were more effective than lower rates for kochia control. However, all Alion plus Sencor treat­ments were better than Sharpen-containing tank mixes 91 DAT.

Weed Control With Postemergence Applications Of Status, Armezon, Atrazine, Corvus, Verdict, And Roundup Powermax In Irrigated Corn, R. Currie, P. Geier

Kansas Agricultural Experiment Station Research Reports

All postemergence herbicides provided greater than 98% control of quinoa, common sunflower, Palmer amaranth, and green foxtail. Crabgrass and Russian thistle were more difficult to control. All postemergence herbicides except Roundup PowerMax (glypho­sate) alone controlled Russian thistle and crabgrass greater than 89%. Diflexx (dicamba) plus Roundup PowerMax was slightly more efficacious on kochia than Status (diflufen­zopyr + dicamba) plus Armezon (topramezone) with atrazine and Roundup Power­Max, and all other herbicides were intermediate for kochia control. Corn yields did not differ between herbicide treatments. However, all herbicides increased grain yields.

Weed Control With Accent, Callisto, Isoxadifen, Impact, Cinch, Dicamba, And Atrazine In Irrigated Corn, R. Currie, P. Geier

Kansas Agricultural Experiment Station Research Reports

Some timings and combinations of the herbicides tested in this study controlled Palmer amaranth, kochia, quinoa, Russian thistle, and green foxtail from 95 to 100% 51 days after postemergence application (DA-B). Accent (nicosulfuron) plus Callisto (mesotri­one) and isoxadifen alone postemergence provided 88% Palmer amaranth control at 51 DA-B. Kochia control was 92 and 90% when Accent plus Callisto and isoxadifen alone or with atrazine and Dicamba XP (dicamba) was applied postemergence following Cinch (S-metolachlor) preemergence application. Crabgrass control with preemergence followed by postemergence treatments exceeded 89%. Crabgrass control was 83 and 88% when no preemergence herbicide was applied …

Weed Control With Single Or Sequential Herbicide Applications In Acetolactase Synthase-Tolerant Grain Sorghum, R. Currie, P. Geier

Kansas Agricultural Experiment Station Research Reports

Palmer amaranth control was best when Resolve (rimsulfuron) plus Harmony GT (thifensulfuron) and Abundit Extra (glyphosate) were applied 15 days preplant fol­lowed by Zest (nicosulfuron) and atrazine postemergence, or by Zest plus atrazine alone postemergence. Palmer amaranth control was less than 80% with all other herbicide treatments. Preemergence herbicides alone provided less than 60% green foxtail control at 53 days after postemergence applications, and Zest plus atrazine alone postemergence controlled green foxtail 70%. Sequential applications of preemergence and postemer­gence herbicides were needed to provide the best green foxtail control. The relatively low weed control provided by these treatments may be …

Efficacy Of Preemergence Or Early Postemergence Weed Control With Keystone Nxt, Hornet Wdg, Atrazine, Surestart Ii, Lumax Ez, And Resicore, R. Currie, P. Geier

Kansas Agricultural Experiment Station Research Reports

Control of buffalobur was complete regardless of herbicide used. Velvetleaf and punc­turevine control, although not perfect, was excellent by all herbicides. The premix of SureStart II (acetochlor + flumetsulam + clopyralid) with atrazine and Durango DMA (glyphosate) applied early postemergence and the preemergence herbicides Resicore (acetochlor + mesotrione + clopyralid) with atrazine and Lumax EZ (S-metolachlor + atrazine + mesotrione) provided excellent Palmer amaranth control. The early pos­temergence treatment of SureStart II plus atrazine and Durango DMA was the only treatment to provide excellent control of green foxtail.

Efficacy Of Preemergence And Sequential Applications With Corvus, Atrazine, Starane, Balance, Anthem, Capreno, Diflexx And Halex Gt In Irrigated Corn, R. Currie, P. Geier

Kansas Agricultural Experiment Station Research Reports

Control of kochia and quinoa was 98 to 100% regardless of herbicide treatment at 48 days after post applications (DAPT), and 95% or more with all herbicides for Russian thistle. Palmer amaranth control was slightly less with preemergent (PRE) treatments alone compared to sequential treatments. Corvus (isoxaflutole + thiencarbazone) plus atrazine, Starane Ultra (fluroxypyr), and nonionic surfactant preemergence controlled crabgrass by 88%; whereas all other treatments provided 91% or more crabgrass control. Corn with the best herbicide treatments yielded 33 to 66 bu/a more than untreated corn.

Weed Control And Crop Injury With Single Or Sequential Herbicide Applications In Grain Sorghum, R. Currie, P. Geier

Kansas Agricultural Experiment Station Research Reports

The preemergence application of Dual II Magnum (S-metolachlor) improved the over­all weed control compared to single postemergence treatments. Excessive rainfall after preemergence application compromised all treatments, producing abnormally low weed control.

Efficacy Of Anthem Maxx, Solstice, Cadet, Roundup Powermax, And Competitive Standards In Irrigated Corn, R. Currie, P. Geier

Kansas Agricultural Experiment Station Research Reports

Control of Palmer amaranth and green foxtail was generally best when herbicides were applied as sequential treatments of preemergence (PRE) followed by late postemergence (LPOST) or as postemergence (POST) alone. Velvetleaf and puncturevine control was 95 and 93% or more, respectively, regardless of herbicide or application timing. Corn receiving herbicide treatments yielded 42 to 72 bu/a more grain than non-treated corn.

Preemergence Weed Control With Fultime Nxt And Competitive Standards In Grain Sorghum, R. Currie, P. Geier

Kansas Agricultural Experiment Station Research Reports

At 71 days after treatment, FulTime NXT (acetochlor + atrazine) at 2.5 or 3.0 qt/a and Lumax EZ (S-metolachlor + atrazine + mesotrione) at 2.0 qt/a were the only treatments to control Palmer amaranth at 90% or more. All treatments provided similar velvetleaf control. Green foxtail control was 75 to 83% with all rates of FulTime NXT or Lumax EZ. Sorghum receiving FulTime NXT at 2.5 or 3.0 qt/a or Lumax EZ yielded significantly more than the control treatments.