(217) Preemergence Weed Control in Container-grown Herbaceous Perennials

During the 2005 season, three preemergence herbicides were applied to four container-grown herbaceous perennials and evaluated for weed control, phytotoxicity, and effect on plant growth. The herbicides and application rates were: 1) Pendimethalin (Pendulum 2G) 2.24, 4.48, and 8.96 kg/ha; 2) Trifluralin and Isoxaben (Snapshot 2.5 TG) 2.8, 5.6, and 11.2 kg/ha; and 3) S-metolachlor (Pennant Magnum 7.6 EC) 2.8, 5.6, and 11.2 kg/ha. Herbicides were applied to Coral Bells (Heuchera sanguinea), Hopflower Oregano (Origanum libanoticum), CORONADO™ Hyssop (Agastache aurantiaca), and SPANISH PEAKS™ Foxglove (Digitalis thapsi). Treatments were applied twice with 30 days between applications. Plants were evaluated for phytotoxicity after 1, 2, and 4 weeks after applying herbicide treatments. No phytotoxicity symptoms were apparent on any of the plants treated with Pendulum, and plant size (dry mass) was not affected. Snapshot resulted in visual phytotoxicity with Digitalis and Heuchera at the higher rates and also resulted in smaller plants. Pennant Magnum caused phytotoxicity at all rates in all plants and resulted in significantly smaller plants than the control. Weed control was very good with all herbicides, but did not control every weed.

Download Full-text

Preemergent Weed Control in Container-grown Herbaceous Perennials

Journal of Environmental Horticulture ◽

10.24266/0738-2898-7.1.14 ◽

1989 ◽

Vol 7 (1) ◽

pp. 14-16

Author(s):

Julie Schuett ◽

James E. Klett

Keyword(s):

Plant Growth ◽

Weed Control ◽

Ajuga Reptans ◽

Herbaceous Perennials ◽

Sphagnum Peat ◽

Preemergence Herbicides ◽

Dicentra Spectabilis

Abstract This study was conducted to evaluate several preemergence herbicides for weed control, effects on plant growth, and phytotoxicity to container-grown herbaceous perennials. Surflan (Oryzalin) was applied at 0, 2.24, 4.48, 6.72 kg ai/ha (0, 2, 4, 6 lb ai/A), Ronstar (Oxadiazon) at 0, 4.48, 8.96, 13.44 kg ai/ha (0, 4, 8, 12 lb ai/A), and Rout (Oxyfluorfen + Oryzalin) at 0, 3.36, 6.72, 10.08 kg ai/ha (0, 3, 6,9 lb ai/A) to container-grown Ajuga reptans atropurpurea L. (carpet bugle), Campanula garganica major (Ten.) Fiori (bellflower), and Liatris spicata (L.) Willd. (spike gayfeather). Additionally, Devrinol (Napropamide) and Treflan (Trifluralin) were each applied at 0, 4.48, 8.96, 13.44 kg ai/ha (0, 4, 8, 12 lb ai/A) to Astilbe × arendsii Arends. (false spirea) and Dicentra spectabilis (L.) Lem. (bleeding heart). Plants were grown in 2.54 1 (#1) containers in a medium of sand, topsoil, and sphagnum peat (1:1:1 by vol). Weed control was acceptable with all herbicides except Surflan at 2.24 kg ai/ha (2 lb ai/A) which did not control shepardspurse. Surflan applied at either 4.48 (41b ai/A) or 6.72 kg ai/ha (61b ai/A) rate resulted in phytotoxicity of carpet bugle, while the 6.72 kg ai/ha rate (6 lb ai/A) significantly reduced plant growth.

Download Full-text

Preemergent Weed Control in Container-grown Herbaceous Perennials

HortScience ◽

10.21273/hortsci.31.4.660c ◽

1996 ◽

Vol 31 (4) ◽

pp. 660c-660

Author(s):

James E. Klett ◽

David Hillock ◽

David Staats

Keyword(s):

Data Analysis ◽

Plant Growth ◽

Weed Control ◽

Sea Urchin ◽

Dry Weight ◽

The Other ◽

Herbicide Application ◽

Herbaceous Perennials ◽

Gypsophila Paniculata ◽

Herbicide Treatments

Herbicides were applied to container-grown herbaceous perennials and evaluated on the basis of weed control, phytotoxicity, and effect on plant growth. During the 1995 season six preemergent herbicides [(in kg·ha–1) Napropamide (Devrinol 10G), 4.5 and 9.1; Isoxaben (Gallery 75DF), 1.1 and 2.3; Oxadiazon (Ronstar 2G), 4.5 and 9.1; Oxyfluorfen + Oryzalin (Rout 3G), 3.4 and 13.6; Oryzalin (Surflan AS), 2.8 and 4.5; and Trifluralin (Treflan 5G) 4.5 and 9.1, were tested on Callirhoe involucrata, Delosperma nubigenum, Dendranthemum ×morifolium `Jennifer', Festuca cinerea `Sea Urchin', and Gypsophila paniculata `Fairy's Pink'. Isoxaben (both rates) resulted in visual phytotoxicity symptoms and sometimes death to Dendranthemum. Oxadiazon (9.1 kg·ha–1) and Oxyfluorfen + Oryzalin (both rates) resulted in plant chlorosis and necrosis to Delosperma soon after herbicide application, but plants outgrew herbicide damage. Napropamide (both rates), applied to Delosperma, resulted in less dry weight when compared to some of the other herbicide treatments. Oryzalin (4.5 kg·ha–1) resulted in visual phytotoxicity and less plant dry weight to Festuca. Data analysis revealed no significant differences in Callirhoe and Gypsophila. In general, most herbicides controlled weeds effectively.

Download Full-text

Weed Control in Container-grown Herbaceous Perennials

HortScience ◽

10.21273/hortsci.29.2.95 ◽

1994 ◽

Vol 29 (2) ◽

pp. 95-97 ◽

Cited By ~ 18

Author(s):

Jeffrey F. Derr

Keyword(s):

Weed Control ◽

Echinacea Purpurea ◽

Fresh Weight ◽

Weed Species ◽

Herbaceous Perennials ◽

Rudbeckia Hirta ◽

Purple Coneflower ◽

Application Rates ◽

Excellent Control ◽

Preemergence Herbicides

Tolerance of transplanted black-eyed Susan (Rudbeckia hirta var. pulcherrima Farw.), lanceleaf coreopsis (Coreopsis lanceolata L.), shasta daisy (Chrysanthemum × superbum Bergmans ex. J. Ingram), purple coneflower [Echinacea purpurea (L.) Moench.], and blanket flower (Gaillardia aristata Pursh) to preemergence herbicides was evaluated in container trials. Herbicides were applied at the maximum use rate and twice the maximum use rate. Dithiopyr, pendimethalin, and prodiamine provided excellent control of spotted. spurge (Euphorbia maculata L.) and yellow woodsorrel (Oxalis stricta L.) with little injury to the five herbaceous perennials. DCPA, oxadiazon, and metolachlor were tolerated by all treated species, but these chemicals provided lower control of one or both weed species. Oryzalin, isoxaben + trifluralin, and napropamide caused unacceptable injury and shoot fresh-weight reductions in some of the perennials at one or both application rates. Chemical names used: dimethyl 2,3,5,6-tetrachloro-1,4-benzenedicarboxylate (DCPA); S,S-dimethyl 2-(difluoromethyl) -4-(2 -methylpropyl)-6-trifluoromethyl-3,5-pyridinedicarbothioate(dithiopyr);N-[3-(1-ethyl-1-methylpropyl)-5-isoxazolyl]-2,6-dimethoxybenzamide(isoxaben); 2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide(metolachlor);N,N-diethyl-2-(l-naphtha1enenyloxy) propanamide(napropamide);4-(dipropylamino)-3,5-dinitrobenzenesulfonamide (oryzalin);3-[2,4-dichloro-5-(1-methylethoxy)phenyl]-5-(1,1-dimethylethy1)-l,3,4-oxadiazol-2-(3H)-one (oxadiazon); N-(1-ethylpropyl) -3,4-dimethyl-2,6-dinitrobenzamine (pendimethalin); N,N-di-n-propyl-2,4-dinitro-6-(trifluoromethyl)-m-phenylenediamine (prodiamine); 2,6-dinitro-N,N-dipropyl-4-(trifluoromethyl)benzamine (trifluralin).

Download Full-text

HPPD-Inhibiting Herbicides Alone or in Tank-Mix with Atrazine in Elephant Grass

Journal of Agricultural Science ◽

10.5539/jas.v9n11p234 ◽

2017 ◽

Vol 9 (11) ◽

pp. 234

Author(s):

Alexandre M. Brighenti ◽

Juarez C. Machado ◽

Francisco J. S. Ledo ◽

Leonardo H. F. Calsavara ◽

Yago V. Guerra Varotto

Keyword(s):

Weed Control ◽

Rio De Janeiro ◽

Mineral Oil ◽

Minas Gerais ◽

Forage Yield ◽

Elephant Grass ◽

Application Rates ◽

Minas Gerais State ◽

Herbicide Treatments ◽

Janeiro State

The interference imposed by weeds is one of the most important factors limiting elephant grass forage yield. Two experiments were carried out in 2015/2016 and 2017 to evaluate the selectivity and weed control of 4-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibiting herbicides applied alone or in combination with atrazine in elephant grass. The treatments applied in the experiment conducted in Valença, Rio de Janeiro State, Brazil, were as follows: two rates of mesotrione (0.072 and 0.144 kg ha-1 + 0.5% v/v mineral oil - Assist®), two rates of tembotrione (0.075 and 0.100 kg ha-1 + 0.5% v/v mineral oil - Aureo®), atrazine + mesotrione (1.25 + 0.072 kg ha-1 + 0.5% v/v mineral oil - Assist®), atrazine + tembotrione (1.25 + 0.100 kg ha-1 + 0.5% v/v mineral oil - Aureo®), atrazine + mesotrione (1.25 + 0.072 kg ha-1), atrazine + tembotrione (1.25 + 0.100 kg ha-1) and two checks (weed-free check and weedy check). The same herbicide treatments and a check without application were applied in an experiment conducted in Coronel Pacheco, Minas Gerais State, Brazil. Two application rates of mesotrione with the addition of mineral oil or the tank mixture of atrazine plus mesotrione, with or without the addition of mineral oil, did not provide injuries capable to reduce elephant grass forage yield. Tembotrione was phytotoxic to elephant grass when applied with mineral oil. Atrazine plus tembotrione in a tank-mix, with or without mineral oil, were also phytotoxic to elephant grass. All treatments provided satisfactory weed control.

Download Full-text

Preemergence Weed Control in Gladiolus Cormels

Weed Science ◽

10.1017/s004317450006817x ◽

1986 ◽

Vol 34 (6) ◽

pp. 957-960 ◽

Cited By ~ 2

Author(s):

James P. Gilreath

Keyword(s):

Plant Growth ◽

Weed Control ◽

Minimal Effect ◽

Amaranthus Hybridus ◽

Eleusine Indica ◽

Preemergence Herbicides ◽

Smooth Pigweed ◽

Gladiolus Plant

Multiple applications of several preemergence herbicides were evaluated for weed control and for phytotoxicity to gladiolus (Gladiolus X hortulanus L.) grown from cormels in 1984 and 1985. Oryzalin [4-(dipropylamino)-3,5-dinitrobenzenesulfonamide] consistently provided acceptable control of southern crabgrass [Digitaria ciliaris (Retz.) Koel. # DIGSP], goosegrass [Eleusine indica (L.) Gaertn. # ELEIN], and smooth pigweed (Amaranthus hybridus L. # AMACH) and had minimal effect on gladiolus plant growth even after four applications. Pronamide [3,5-dichloro (N-1,1-dimethyl-2-propynyl)benzamide], alachlor [2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl)acetamide], and metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide] provided erratic weed control and reduced yields of gladiolus corms.

Download Full-text

Effect of row width on herbicide and cultivation requirements in row crops

American Journal of Alternative Agriculture ◽

10.1017/s0889189300004756 ◽

1992 ◽

Vol 7 (4) ◽

pp. 161-167 ◽

Cited By ~ 42

Author(s):

Frank Forcella ◽

Mark E. Westgate ◽

Dennis D. Warnes

Keyword(s):

Weed Control ◽

Crop Yield ◽

Crop Yields ◽

Row Crops ◽

Low Input ◽

Application Rates ◽

Row Width ◽

Herbicide Treatments ◽

Herbicide Use

AbstractCrops grown in narrow rows (NR, 0.25 to 0.38 m) shade weed seedlings more than do those grown in traditional wide rows (WR, 0.76 m). NR crops may require less herbicide and interrow cultivation than WR crops for equally effective weed control. This hypothesis was tested by comparing weed control and crop yield in NR and WR crops when the following percentages of recommended application rates (RAR) of standard herbicides were applied: soybean, 0, 50 and 100%; sunflower, 0, 25, 50, and 100%; and corn, 0, 33, and 100% in three separate sets of experiments conducted over 2, 3, and 4 years, respectively. In all treatments with 100% RAR, excellent weed control prevented reductions in crop yield. When only 25 to 50% RAR was applied, weed control was consistently high in NR (82 to 99% control), but variable in WR (42 to 99% control). Weed control and crop yields typically were lowest in NR without herbicides. Interrow cultivation controlled 0 to 81% of weeds in WR crops. In reduced herbicide treatments (25 to 50% RAR), yields of NR soybean and sunflower typically were about equal to those in WR with 100% RAR, but NR corn yields were about 10% less. Considering the reduced herbicide use and lower weed control costs, planting corn, soybean, and sunflower in narrow rows may represent a practical form of low-input production of these important crops.

Download Full-text

Response of Dianthus barbatus L. To Preemergence Herbicides

Journal of Environmental Horticulture ◽

10.24266/0738-2898-6.3.101 ◽

1988 ◽

Vol 6 (3) ◽

pp. 101-104

Author(s):

Julie A. Jacobson ◽

James E. Klett

Keyword(s):

Plant Growth ◽

Weed Control ◽

Control Plant ◽

Growing Season ◽

Annual Bluegrass ◽

Weed Seeds ◽

Dianthus Barbatus ◽

Preemergence Herbicides ◽

Common Groundsel

Six different preemergence herbicides including one herbicide combination were applied to container-grown Dianthus barbatus L. (Sweet William) and evaluated for their effects on weed control, plant growth and phytotoxicity. Napropamide (Devrinol 10G), oryzalin (Surflan 40.4% AS), oxyfluorfen + oryzalin (Rout GS-3G), oxadiazon (Ronstar 2G), metolachlor (Dual 8EC), simazine (Princep 4G) and Dual and Princep were applied to container-grown Sweet William and studied for a growing season. Weed seeds sown were yellow foxtail, annual bluegrass, common groundsel, common chickweed, and creeping woodsorrel. Devrinol, Surflan, and Rout GS resulted in the best weed control without affecting the overall growth of Sweet Wiliam or resulting in any phytotoxicity at rates applied. Dual and Princep resulted in phytotoxicity at all rates applied on Sweet William to a degree that would make the plants unsalable.

Download Full-text

The Effect of Composted Organic Wastes on Weed Control Provided by Preemergence Herbicides

HortScience ◽

10.21273/hortsci.32.3.470e ◽

1997 ◽

Vol 32 (3) ◽

pp. 470E-470

Author(s):

Jennifer A. Johnson ◽

Larry Kuhns ◽

Tracey Harpster

Keyword(s):

Organic Matter ◽

Sewage Sludge ◽

Weed Control ◽

Dry Weight ◽

Field Studies ◽

Silty Clay ◽

Yard Waste ◽

Application Rates ◽

Preemergence Herbicides ◽

Composted Sewage Sludge

Community waste management programs that include the composting of sewage sludge and yard wastes have become a necessity. Using these composts provides many benefits; however, increased levels of organic matter may reduce the effectiveness of preemergence herbicides. Determining how herbicide application rates may need to be adjusted when composted waste is incorporated into the soil may permit the use of these amendments without any decrease in weed control. This experiment examined the effect of two types of compost (composted sewage sludge and composted yard waste) on the weed control provided by four preemergence herbicides. The soil was a Hagerstown silt loam amended with 10%, 20%, or 30% compost by volume. Each mix was placed in half-gallon cardboard milk cartons. The cartons were seeded at 1/2 and 1/4 inches with a mixture of broadleaved weeds and grasses. Each soil mix was treated with simazine, oxyfluorfen, oryzalin, and metolachlor at two rates. Control was evaluated both visually by number and by the dry weight of the harvested weeds. Preliminary results indicate composted sewage sludge causes a greater reduction in herbicide efficacy than composted yard waste. Oryzalin and metolachlor were affected less than oxyfluorfen or simazine. The experiment was repeated using lower application rates. In one replication the soil mixes from the previous experiment were used. The second replication used a Hagerstown silty clay loam soil with fresh compost. The results of this experiment will provide preliminary information for future field studies designed to determine if the application rates of preemergence herbicides need to be adjusted when fields are amended with composted organic matter.

Download Full-text

Influence of Winter Rye and Preemergence Herbicides on Weed Control in No-tillage Zucchini Squash Production

HortTechnology ◽

10.21273/horttech.15.2.0238 ◽

2005 ◽

Vol 15 (2) ◽

pp. 238-243 ◽

Cited By ~ 6

Author(s):

S. Alan Walters ◽

Scott A. Nolte ◽

Bryan G. Young

Keyword(s):

Weed Control ◽

Cover Crop ◽

Cucurbita Pepo ◽

Amaranthus Retroflexus ◽

Winter Rye ◽

No Tillage ◽

Redroot Pigweed ◽

Herbicide Treatments ◽

Residue Biomass ◽

Preemergence Herbicides

The influence of `Elbon', `Maton', and `Wheeler' winter rye (Secale cereale) with or without herbicide treatments on weed control in no-tillage (NT) zucchini squash (Cucurbita pepo) was determined. `Elbon' or `Maton' produced higher residue biomass, greater soil coverage, and higher weed control compared with `Wheeler'. Although winter rye alone did not provide sufficient weed control (generally <70%), it provided substantially greater redroot pigweed (Amaranthus retroflexus) and smooth crabgrass (Digitaria ischaemum) control (regardless of cultivar used) compared with no winter rye at both 28 and 56 days after transplanting (DAT). No effect (P > 0.05) of winter rye cultivar on early or total squash yield was detected. Although applying clomazone + ethalfluralin to winter rye residues improved redroot pigweed control compared with no herbicide, the level of control was generally not adequate (<85% control) by 56 DAT. Treatments that included halosulfuron provided greater control of redroot pigweed than clomazone + ethalfluralin, and redroot pigweed control from halosulfuron treatments was similar to the weed-free control. However, regardless of year or cover crop, any treatment with halosulfuron caused unacceptable injury to zucchini squash plants which lead to reduced squash yield (primarily early yields). Insignificant amounts of squash injury (<10% due to stunting) resulted from clomazone + ethalfluralin in no-tillage plots during either year. Treatments with clomazone + ethalfluralin had early and total yields that were similar to those of the weed-free control, although this herbicide combination provided less weed control compared with the weed-free control.

Download Full-text

Weed Control and Phytotoxicity of Preemergence Herbicides Applied to Container-grown Herbaceous Plants

HortTechnology ◽

10.21273/horttech.8.3.325 ◽

1998 ◽

Vol 8 (3) ◽

pp. 325-328 ◽

Cited By ~ 1

Author(s):

David Staats ◽

David Hillock ◽

James E. Klett

Keyword(s):

Weed Control ◽

Adventitious Roots ◽

Growth Habit ◽

Substrate Surface ◽

Herbaceous Plants ◽

Control Efficacy ◽

Herbaceous Perennials ◽

Weed Seeds ◽

Vigorous Growth ◽

Preemergence Herbicides

Five preemergence herbicides were applied to seven herbaceous perennials to evaluate weed control efficacy and phytotoxicity. Different species were used each year. The species used during 1992 were coneflower (Rudbeckia fulgida Ait. `Goldstrum'), common foxglove (Digitalis purpurea L. `Excelsior'), Shasta daisy (Leucanthemum ×superbum Bergmans `Alaska'), Stokes's aster (Stokesia laevis Greene `Blue Danube'), and avens (Geum Quellyon Sweet `Mrs. Bradshaw'). The species used in 1993 were woolly yarrow (Achillea tomentosa L.) and woolly thyme (Thymus pseudolanuginosus Ronn.). The herbicides and rates were napropamide (Devrinol 10G) at 4 and 8 lb a.i./acre; metolachlor (Pennant 5G) at 4 and 8 lb a.i./acre; oxyfluorfen+oryzalin (Rout 3G) at 3 and 12 lb a.i./acre; trifluralin (Treflan 5G) at 4 and 8 lb a.i./acre; and oxadiazon (Ronstar 2G) at 4 and 8 lb a.i./acre. Plants were grown in no. 1 containers and weed seeds were sown onto the substrate surface. Two control treatments, no herbicides but with weeds (weedy control), and no weeds or herbicides (weed-free control) also were evaluated. Weed control was effective and similar for all herbicides tested. Napropamide at 8 lb a.i./acre caused stunting in foxglove (20% to 45% less growth compared to weed-free control). Oxyfluorfen + oryzlain at 12 lb a.i./acre caused severe phytotoxicity (≈80% to 95% of plant injured) and stunted the growth (70% to 80% less growth, sometimes plant death) of woolly yarrow. Woolly thyme was stunted by all herbicides when applied at the recommended rates (42% to 97% less growth compared to control) except for oxadiazon and oxyfluorfen + oryzlain. Woolly thyme appeared to be more susceptible to phytotoxicity due to its less-vigorous growth habit and shallow, adventitious roots that were in contact with the herbicide.

Download Full-text