California has abundant wildlands — forests, rangeland, open areas, wildlife refuges and national, state, and local parks — that need protection from invasive plants. Invasive plants affect all Californians by increasing wildfire potential; reducing water resources; accelerating erosion and flooding; threatening wildlife; degrading range, crop and timberland; and diminishing outdoor recreation opportunities. According to the California Invasive Plant Council (Cal-IPC), more than 200 identified plant species harm California's wildlands.
Cal-IPC and the University of California Statewide Integrated Pest Management Program (UC IPM), with funding from the California Department of Pesticide Regulation (DPR) Alliance Grants Program, developed two resources that provide land managers access to the latest information on non-herbicide practices for managing weeds in wildlands. Best Management Practices for Non-Chemical Weed Control is a free downloadable manual. The same information has been incorporated into an interactive online tool called WeedCUT (Weed Control User Tool: weedcut.ipm.ucanr.edu).
"We anticipate WeedCUT will increase the use of more mechanical, physical, or biological practices, and potentially result in the reduction of herbicides used to manage wildland invasive weeds," said area IPM advisor emeritus Cheryl Wilen. "Best Management Practices for Non-Chemical Weed Control and WeedCUT were developed so land managers can become more knowledgeable and skilled in the use of non-herbicide methods as part of an IPM program.”
Knapweed control with a brush cutter. (Photo: Dawn Cunningham)
Best Management Practices for Non-Chemical Weed Control provides comprehensive descriptions of 21 commonly used non-herbicide weed control techniques and biological control agents for 18 invasive plants. Each chapter is the synthesis of research and on-the-ground knowledge from practitioners about non-herbicide methods. The chapters describe how a technique is best applied, the types of invasive plants and environmental conditions where it is most effective, and what its shortfalls might be. Environmental, cultural, and human safety risks are highlighted to help support the safe and effective use of these methods.
WeedCUT is the online version and can be used to learn about the different non-herbicide management methods, including the section on biological control. To filter through the database and learn which management practice to consider for a particular site and invasive plant type, a simple interface allows users to pick characteristics that describe their site and invasive plant problem. The tool then filters through the database to display the practices ranked by efficacy (excellent, good, fair, poor or ineffective). As in the manual, use of the technique and potential hazards are covered.
Best Management Practices for Non-Chemical Weed Control and WeedCUT are designed to be the go-to resources for practitioners that complement their conventional weed management work with non-herbicide techniques or are restricted in their use of herbicides. Both resources will help practitioners manage weeds more effectively.
Person releasing weevils for the biological control of Dalmatian toadflax. (Photo: Lincoln Smith USDA-ARS)
“Many experts in the field have contributed to create the manual and WeedCUT. It has been exciting to see these techniques described and reviewed so carefully. We're looking forward to seeing land managers, as well as all folks fighting weeds, incorporating the information from the manual and WeedCUT into their work,” said Jutta Burger, science program director and project lead with Cal-IPC.
While the manual and tool focus on non-herbicide methods, the hope is future funding can be found to continue the work and integrate herbicide options online.
"Land managers typically use both herbicide and non-herbicide methods, alone and in combination, to manage invasive plants in wildlands," said UC Cooperative Extension advisor and UC IPM-affiliated advisor Tom Getts. "A tool that combined both herbicide and non-herbicide methods would guide land managers to determine the most effective overall management program for their particular site."
Yellow starthistle is an invasive rangeland weed. (Photo: J. M. DiTomaso)
horseweed mature
Posted on
Wednesday, July 14, 2021 at
8:12 AM
- Author:
Tunyalee A. Martin, Jutta Burger, Cheryl A. Wilen, Thomas Getts
Focus Area Tags: Agriculture
Article also published in California Weed Science Society Journal (March 2021 issue)
-Brad
Glyphosate is one of the most commonly used herbicides in orchard crops in California both in terms of treated acres and amount of active ingredient applied. Weed managers are generally familiar with the attributes of glyphosate as a postemergence herbicide. Duke and Powles (2008) published an article in Pest Management Science entitled “Glyphosate: a once-in-a-century-herbicide”. Suffice to say, it's a pretty useful herbicide, if that's your thing. It has also been the subject of several controversies in the past couple of decades.
One of those controversies was a source of frequent extension questions from California farmers and Pest Control Advisors about 10 years ago. In the late 2000's there were several researcher articles from work done in glyphosate-tolerant soybeans that suggested there might be some nontarget impacts of glyphosate on crop nutrient status, plant disease interaction, and microbial community effects. In California tree crops concern generally focused around whether glyphosate in the soil could chelate micronutrients and lead to nutrient deficiencies and/or if repeated use could cause enough glyphosate to accumulate in soil and have direct impacts on the trees.
In a 2012 review article on the impacts of glyphosate in the soil environment, Duke et al. suggested that “significant effects of glyphosate on soil mineral content is unlikely” and there is no clear negative trend in orchard productivity data in California even after decades of glyphosate use. However, because this was a concern for the California orchard crop industries, we conducted a long-term research project from 2013 to 2020 to help address the issue in representative orchard crops.
If you're REALLY interested, the full report was published in summer 2020 as an open-access article in the journal Weed Technology which can be accessed HERE.
If you're only a LITTLE interested, here is the essence of the project conduct at the UC Davis Plant Sciences Field Facility in Davis, CA:
- Crops (three crops were considered separate experiments):
- Almond (Nonpareil on Lovell)
- Prune (Improved French on Lovell)
- Cherry (Coral on Emla-Colt)
- Planting site:
- At planting, all tree sites were excavated with a 36-inch diameter augur to a 2-ft depth
- Half were refilled with the native silty clay loam soil
- Half were refilled with Delhi sandy loam
- Glyphosate treatments:
- From 2014 to 2019, treatments were applied 3 times per season (~between Apr-Nov)
- Rates were 0, 1, 2, or 4 lb ae/A equivalents (Roundup PowerMAX plus ammonium sulfate). Applied to an area of about 6x6 ft around each tree
- In 2014, trunks were protected with cartons, but no trunk protection in 2015-19
- Drench
- In the first two years of treatment (2014 and 2015) there was a split-plot factor in which half of the trees had a small berm built up around the base of the tree and were “drenched” with water to simulate a 1-inch irrigation immediately after each application (intended to increase leaching into the relatively small tree root zone and crown area).
- Evaluations
- In the first year of treatment (2014) leaf samples were collected 14 days after each glyphosate application and assayed for shikimate accumulation (which would indicate direct herbicidal effects of glyphosate).
- In the first two years of treatment, relative chlorophyll content was measured in leaves from each tree 30 days after each glyphosate application (which could indicate either direct glyphosate effects or indirect effects of micronutrient limitations).
- Trunk diameter measurements were made before the first application in 2014 and during the winter after each subsequent season to evaluate relative tree growth.
- After the 6th year of treatment, leaf samples were collected in the fall from each tree but combined over soil type and drench subplots. The nutrient status of these leaf samples was determined by the UC Davis Analytical Lab using appropriate techniques.
- So, to recap, the worst case scenario had:
- Very coarse soil in the planting site of bare root almond, cherry, and prune nursery trees.
- In the first two years, some plots had a simulated acre-inch of irrigation immediately following each glyphosate application.
- The highest rate treatment of 4 lb ae/A glyphosate applied 18 times over a six year period. That's 114 fl oz/A of Roundup PowerMAX at each application. Over the course of the experiment that's 72 lb ae/A glyphosate or 16 gallons of Roundup PowerMAX. It's a lot!
- Results:
- Shikimate levels were similar among treated and non-treated trees with no clear dose-response or soil-related parameters. This suggests little or no direct effect of glyphosate on these tree crops via root uptake even at fairly extreme rates over multiple years.
- Chlorophyll content mostly indicated no differences among treatments. Where there were statistically significant main effects or interactions, there was no consistent pattern with regard to glyphosate rate, coarse soils, and post-treatment drench, which suggests they may be due to random variation or experimental artifacts.
- Leaf nutrient analysis after 6 years of treatment did not provide evidence of negative impacts on crop nutrient status.
- Trunk diameter increase over six growing seasons was not negatively impacted by glyphosate treatments (Figure).
- Observationally, over the six year period, there was no evidence of treatment-related trunk cankers, trunk or limb malformations or unusual die-back.
Scientists will always remind you that you “can't prove a negative”, and that remains true. However, we think these data suggest that it is probably not easy or common for almond, cherry, or prunes to be negatively impacted by glyphosate residues in the soil either due to direct herbicide effects or to micronutrient deficiencies.
Acknowledgments:
This work was initially supported by the Almond Board of California, the California Dried Plum Board and with nursery stock provided by Sierra Gold Nurseries. Over time, the experiments were maintained with general program support from the crop protection industry, orchard commodity groups, and agricultural input suppliers. We gratefully thank our colleagues who contributed to this long-term project along the way.
References:
Duke SO, Powles SB (2008) Mini-review. Glyphosate: a once-in-a-century herbicide. Pest Manag Sci 64:319–325
Duke SO, Lydon J, Koskinen WC, Moorman TB, Chaney RL, Hammerschmidt R (2012) Glyphosate effects on plant mineral nutrition, crop rhizosphere microbiota, and plant disease in glyphosate-resistant crops. J Agric Food Chem 60:10375–10397
Osipitan OA, Yildiz-Kutman B, Watkins S, Brown PH, Hanson BD (2020). Impacts of repeated glyphosate use on growth of orchard crops. Weed Technol. doi: 10.1017/wet.2020.85 (available at: https://www.cambridge.org/core/journals/weed-technology/article/impacts-of-repeated-glyphosate-use-on-growth-of-orchard-crops/26697F334626A587765C75C2B0F76A3D)
This blog originally appeard in the UC Weed Science Blog
https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=46316
weeds bordering avocado orchard
Posted on
Friday, April 30, 2021 at
7:45 AM
- Author:
Brad Hanson and O. Adewale Osipitan
Focus Area Tags: Agriculture
Management of Weeds in Citrus Orchards
A One Hour Webinar
June 19, 2019 from 3-4pm)
Dr. Travis Bean, assistant weed science specialist in UCCE, will discuss the importance of weed management in citrus, tree age and variety considerations, scouting and weed identification, cultural and mechanical practices, and pre- and post-emergence herbicides. One DPR CE unit (other) and one CCA CE unit (IPM) are pending.
Register in advance for the webinar by clicking on the event link above.
And there are more coming:
https://ucanr.edu/sites/ucexpertstalk/
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weeds
Posted on
Monday, June 3, 2019 at
6:29 AM
It really has gotten out of hand - Hairy Fleabane and Horseweed which are both Conyza weed species that have run rampant this year because of the extra rain. It's also because they have become resistant to glyphosate herbicide. The problem has shown up all over the US and other parts of the world. Gradually as resistance has grown and their resistant fairy seeds have floated wherever the winds go, the weed is having a field day everywhere in your backyard, in your orchard, in the sidewalk. It's not just abandoned areas, but in actively managed areas where Cal Trans is doing its best.
Citrus growers who have not used preemergents in years or never used them have turned to various cocktails to knock it out.
A good description of the biology and care of Conyza can be found at:
https://anrcatalog.ucanr.edu/pdf/8314.pdf
And we along with others have written about this problem in the past -
//ucanr.edu/blogs/topics/index.cfm tagname=Conyza ,
//ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=10648 ,
//ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=20061
But this year has been exceptional in the ubiquity of this plant. Something more than glyphosate is called for at this point. Glufosinate is a postemergent herbicide somewhat similar to glyphosate in name only and more expensive. It is a broadspectrum herbicide that is effective with thorough coverage on younger stages of conyza and other weeds. It will take some learning to get the best effect out of it. Citrus growers have been able to use it for several years now and have enjoyed its effectiveness. We are currently working on an IR-4 registration (http://ir4.rutgers.edu/) for avocados. It is currently not registered for use in avocado.
Mature avocados are pretty good about controlling any weeds in their own orchards through ground shading and self mulching, but conyza has become a problem in young orchards. And this new herbicide could help.
Posted on
Friday, August 18, 2017 at
4:51 AM
Title: Area Livestock and Natural Resources Advisor
Specialty: Rangeland Ecology and Management, Rangeland Conservation, Grazing Management, Conservation of Biological Diversity, Watershed Protection and Management.
County: San Benito County
Address:
Cooperative Extension San Benito County
3228 Southside Road
Hollister, CA 95023
Phone: 831-637-5346 x14
Email: drorao@ucanr.edu
Do you have yellow starthistle, Italian thistle, Himalaya blackberry, white top, or other common Central Coast rangeland weeds on your ranch? If so, you may be wondering which herbicides are most effective, how much they cost, what is required to purchase and spray a particular herbicide, when to spray, whether the herbicide affects grasses or clovers, and if the herbicide is safe for your livestock and pets. Many Central Coast rangeland landowners have been asking these same questions. So, I compiled this information in two tables. Table 1 shows some of our common rangeland weeds and different herbicide treatment options. Table 2 lists six of the most commonly used rangeland herbicides, and answers questions about cost, when to spray, purchasing requirements, affected plants, and grazing/pet restrictions. All of this information is already available from a variety of sources, but I have put it together in two easy to use reference tables. The tables are self-explanatory for the most part, but the information below may clarify a few things.
Integrated Pest Management (IPM)
IPM is a weed management approach that uses multiple control methods. Control methods could include mechanical control, manual control, grazing, seeding, herbicide, etc. The most effective options will depend on the particular species you are trying to control. This blog post focuses on herbicide because I am often asked about chemical treatment options. However, your weed control efforts will likely be most successful if you use a variety of methods.
Operator ID's, Restricted Materials Permits, & Private Applicator Certificates
Most of the herbicides in Table 2 are general use pesticides, meaning that you only need an operator ID to purchase and use them (Carbonaro, pers. comm.). Operator ID's are free and can be obtained from your County Agricultural Commissioner's office. No test is required. But, you'll need to show a property map in order to get your operator ID.
One herbicide in Table 2, 2, 4-D, is a California state restricted pesticide when applied on rangelands. Before you can purchase or spray California state restricted pesticides, two things are required: a Private or Commercial Applicator Certificate and a restricted materials permit. You can get a Private Applicator Certificate from your County Ag Commissioner's office. This requires taking a free test. The test is based on Pesticide Safety: A Reference Manual for Private Applicators, 2nd Ed., published by the University of California. This book can be purchased from most County Ag Commissioner or UC Cooperative Extension offices or online at: http://anrcatalog.ucanr.edu/Details.aspx?itemNo=3383. Once you have your Private Applicator Certificate you'll be able to obtain a restricted materials permit, again from your County Ag Commissioner's office. Alternatively, you can hire a licensed pest control business to purchase and spray California state restricted pesticides.
Read Labels, Follow Federal, State & Local Regulations, and Report Pesticide Use to Your County Ag Department
Although Table 2 includes information from the herbicide labels, it is not a substitute for reading the entire herbicide label before you spray (Carbonaro, pers. comm.). Always read the label before using any of these herbicides. In California, in addition to following the label, applicators will also need to follow federal, state, and local regulations. And, remember that you should submit a pesticide use report to your County Agricultural Commissioner's office for all pesticides used on rangelands.
For additional information about weeds and how to manage them, check out this website: http://wric.ucdavis.edu. The Invasive Thistles of Bay Area Counties & Herbicides for Controlling Thistles Handout compiled by Guy Kyser, UC Cooperative Extension Specialist in Weed Science at UC Davis is a great resource and is attached at the bottom of this blog post.
References
Carbonaro, D. 2017. Personal communication, 4/16/2017. Carbonaro is a Senior Biologist/Inspector with the San Benito County Agricultural Commissioner's Office.
DiTomaso, J.M. G.B. Kyser et al. 2013. Weed Control in Natural Areas in the Western United States. WRIC, UC.
Kyser, G. Unpublished. Invasive Thistles of Bay Area & Herbicides for Controlling Thistles.
Table 1. Common Central Coast Rangeland Weeds
PlantSpecies
|
Herbicides Options Approved for useon CaliforniaRangelands
|
Rangeland Herbicides Known to beEffective
|
|
Bullthistle
(Cirsium vulgare)
|
2, 4-D (Severalnames) Aminopyralid(Milestone) Clopyralid(Transline) Dicamba (Banvel,Clarity)
Triclopyr (Garlon 3A/Garlon 4Ultra)Chlorsulfuron(Telar)
Imazapyr (Arsenal,Polaris)
|
Milestone, Transline, Capstone (=Milestone + Garlon),Garlon, Roundup (Kyser,unpublished)
2,4-D is often used because it is inexpensive. However, itis not as effective as otherherbicides.
|
Bull thistle weed report:
|
http://wric.ucdavis.edu/information/natural%20areas/wr_C/Cirsium_vulgare.pdf
|
Cocklebur (commonand spiny cocklebur) (Xanthium strumarium) (Xanthium spinosum)
|
2, 4-D (Severalnames) Aminopyralid(Milestone) Clopyralid(Transline) Dicamba (Banvel,Clarity) Fluroxypyr (VistaXRT)
Triclopyr (Garlon 4 Ultra, RemedyUltra)Glyphosate (Roundup, Accord XRT II,and others)
Imazapyr (Arsenal,Polaris) Sulfosulfuron(Outrider)
|
Aminopyralid(Milestone) Clopyralid(Transline)
|
Cocklebur weed report:
|
http://wric.ucdavis.edu/information/natural%20areas/wr_X/Xanthium_spinosum-strumarium.pdf
|
Fiddleneck (Menziesandcoastfiddleneck) (Amsinckiamenziesii)(Amsinckia menziesiivar. intermedia)
|
Aminopyralid(Milestone)
Glyphosate (Roundup, Accord XRT II,and others)
Chlorsulfuron(Telar)Imazapyr (Arsenal,Polaris) Sulfosulfuron(Outrider)Hexazinone (VelparDF)
|
Aminopyralid(Milestone) Chlorsulfuron(Telar)
|
Fiddleneck weedreport:
|
http://wric.ucdavis.edu/information/natural%20areas/wr_A/Amsinckia.pdf
|
Foxtail (Mediterraneanand harebarley)
(Hordeum marinumssp.gussonianum) (Hordeum murinumssp.leporinum)
|
Glyphosate (Roundup, Accord XRT II,and others)
Imazapyr (Arsenal,Polaris) Rimsulfuron(Matrix)
Sulfometuron + chlorsulfuron(LandmarkXP)
Sulfosulfuron(Outrider)Hexazinone (VelparL)
|
Glyphosate (Roundup, Accord XRT II, and others) iseffective, but is nonselective, so will kill most other plants as well.If glyphosate is to be used, reseed to reduce bare groundand encroachment of other weedspecies.
Rimsulfuron (Matrix) will likely control control foxtail,based on limiteddata.
|
Foxtail weedreport:
|
http://wric.ucdavis.edu/information/natural%20areas/wr_H/Hordeum_marinum-murinum.pdf
|
Frenchbroom
(Genista monspessulana)
|
Triclopyr (Garlon 3A, Garlon 4Ultra,PathfinderII)
Aminopyralid + triclopyr(Capstone) Triclopyr + 2,4-D(Crossbow)
Glyphosate (Roundup, Accord XRT II,and others)
Imazapyr (Arsenal,Polaris)
|
Triclopyr (Garlon 3A, Garlon 4 Ultra, PathfinderII)
Glyphosate (Roundup, Accord XRT II, and others) iseffective, but resprouts will need to be controlled. Glyphosateis nonselective, so will kill most other plants as well. Ifglyphosate is to be used, reseed to reduce bare groundand encroachment of other weedspecies.
|
French broom weedreport:
|
http://wric.ucdavis.edu/information/natural%20areas/wr_G/Genista.pdf
|
Goatgrass (jointed and barbgoatgrass) (Aegilops cylindrica) (Aegilops triuncialis)
|
Glyphosate (Roundup, Accord XRT II,and others)
Sulfometuron + chlorsulfuron(LandmarkXP)
|
Research is currently being conducted to identify most effective options for goatgrass.
|
Goatgrass weedreport:
|
http://wric.ucdavis.edu/information/natural%20areas/wr_A/Aegilops_cylindrica-triuncialis.pdf
|
Himalayablackberry
(Rubus armeniacus)
|
Dicamba (Banvel,Clarity) Fluroxypyr (VistaXRT)
Triclopyr (Garlon 3A, Garlon 4Ultra,PathfinderII)
Aminopyralid + triclopyr (Capstone) Glyphosate (Roundup/Accord XRT II,and others)
Hexazinone (VelparL) Tebuthiuron(Spike)
|
Triclopyr (Garlon 3A, Garlon 4 Ultra, Pathfinder II) canbe effective on smallindividuals.
Glyphosate (Roundup/Accord XRT II, and others) canbe effective, but may requireretreatment.
|
Himalaya blackberry weed report:
|
http://wric.ucdavis.edu/information/natural%20areas/wr_R/Rubus.pdf
|
Italian thistle
(Carduus pycnocephalus)
|
2, 4-D (Severalnames) Aminopyralid(Milestone) Aminopyralid + 2,4-D (ForefrontHL) Aminopyralid + triclopyr(Capstone) Clopyralid(Transline)
Dicamba (Banvel,Clarity) Fluroxypyr (VistaXRT)
Triclopyr (Garlon 3A, Garlon 4Ultra)Triclopyr + 2,4-D(Crossbow)
Glyphosate (Roundup, Accord XRT II,and others)
Chlorsulfuron(Telar)Imazapyr (Arsenal,Polaris) Hexazinone (VelparL)
|
Aminopyralid (Milestone) is highly effective on thistles.
Milestone, Transline, Capstone (=Milestone + Garlon),Garlon, Roundup (Kyser,unpublished)
2,4-D is often used because it is inexpensive. However, itis not as effective as otherherbicides.
|
Italian thistle weedreport:
|
http://wric.ucdavis.edu/information/natural%20areas/wr_C/Carduus_acanthoides-nutans-pycnocephalus-tenuiflorus.pdf
|
Medusahead (Taeniatherumcaput
-medusae)
|
Aminopyralid(Milestone)
Glyphosate (Roundup, Accord XRT II,and others)
Rimsulfuron(Matrix) LandmarkXP
|
Aminopyralid (Milestone) provided up to 90% controlof medusahead based on research in the CentralValley.
|
Medusahead weedreport:
|
http://wric.ucdavis.edu/information/natural%20areas/wr_T/Taeniatherum.pdf
|
Milkthistle
(Silybum marianum)
|
2, 4-D (Severalnames) Aminopyralid(Milestone) Clopyralid(Transline) Dicamba (Banvel,Clarity) Chlorsulfuron(Telar)Rimsulfuron(Matrix)
|
Milestone, Transline, Capstone (=Milestone + Garlon),Garlon, Roundup (Kyser,unpublished)
|
Milk thistle weedreport:
|
http://wric.ucdavis.edu/information/natural%20areas/wr_S/Silybum.pdf
|
Purple starthistle
(Centaurea calcitrapa)
|
2, 4-D (Severalnames) Aminopyralid(Milestone) Clopyralid(Transline) Dicamba (Banvel,Clarity)
Glyphosate (Roundup, Accord XRT II,and others)
Hexazinone (VelparL)
|
Milestone, Transline, Capstone (=Milestone + Garlon),Garlon, Roundup (Kyser,unpublished)
|
Purple starthistleweed report:
|
http://wric.ucdavis.edu/information/natural%20areas/wr_C/Centaurea_calcitrapa-iberica.pdf
|
Tumbleweed(Russian thistle)
(Salsola tragus)
|
2, 4-D (SeveralNames) Aminocyclopyrachlor +Aminopyralid(Milestone) Dicamba (Banvel,Clarity)
Triclopyr (Garlon 3A, Garlon 4Ultra)Glyphosate (Roundup, Accord XRT II,and others)
Chlorsulfuron(Telar)Imazapyr (Arsenal,Polaris) Hexazinone (VelparL)
|
Research is currently being conducted to identify most effective options fortumbleweed.
|
Tumbleweed weedreport:
|
http://wric.ucdavis.edu/information/crop/natural%20areas/wr_S/Salsola_paulsenii-tragus.pdf
|
Whitetop/hell weed
(Cardaria draba)
|
2, 4-D (Severalnames) Dicamba + 2,4-D
Glyphosate (Roundup, Accord XRT II,and others
Chlorsulfuron(Telar)Imazapyr (Arsenal,Polaris)
|
Chlorsulfuron (Telar) is one of the best control optionsfor plants in the Cardariagenus.
2,4-D is often used because it is inexpensive. However, itis not as effective as otherherbicides.
|
Whitetop weedreport:
|
http://wric.ucdavis.edu/information/natural%20areas/wr_C/Cardaria_chalepensis-draba-pubescens.pdf
|
Yellowstarthistle
(Centaurea solstitialis)
|
2, 4-D (Severalnames) Aminopyralid(Milestone) Clopyralid(Transline) Dicamba (Banvel,Clarity)
Triclopyr (Garlon 3A, Garlon 4Ultra)Glyphosate (Roundup, Accord XRT II,and others)
Chlorsulfuron(Telar)Imazapyr (Arsenal,Polaris) Hexazinone (VelparL)
|
Aminopyralid (Milestone) is the best option to controlyellow starthistle.
Clopyralid (Transline) is also veryeffective.
Glyphosate (Roundup, Accord XRT II, and others) is thebest option in the lateseason.
|
Yellow starthistleweedreport:
|
http://wric.ucdavis.edu/information/natural%20areas/wr_C/Centaurea_solstitialis.pdf
|
Table 2. Commonly Used Rangeland Herbicides, Including When and How to Use Them
Chemical Name/Product Name1
|
Price2*
|
Registered
for useonCalifornia rangelands3
|
Requirements to Purchase/Spray Herbicide3
|
Preemergent/ Postemergent1
|
Best time tospray4
|
TargetedPlants4
|
Triclopyr(Garlon 3A/Garlon 4Ultra,Remedy Ultra,PathfinderII)
|
$70/gallon
|
Yes
|
Operator ID#
|
Postemergent
|
Spray after all of theweed seed has germinated,but before the plants getbig.
|
Kills broadleaves, but not grasses
Killsclovers5
|
Aminopyralid(Milestone)
|
$300/gallon
|
Yes
|
Operator ID#
|
Preemergentand postemergent
|
January -March
|
Kills thistles andlegumes, and some otherbroadleaves, but notgrasses
Killsclovers5
|
Glyphosate (Roundup, Accord XRT II, and others)
|
$21/gallon
|
Yes
|
Operator ID#
|
Postemergent
|
Spray after all of theweed seed has germinated,but before the plants getbig.
|
Kills any greenvegetation. Tree leaves can be sprayed, but it will not be effectiveifsprayed on treetrunks.
|
Chemical Name/Product Name1
|
Price2*
|
Registered
for useonCalifornia rangelands3
|
Requirements to Purchase/Spray Herbicide3
|
Preemergent/ Postemergent1
|
Best time tospray4
|
TargetedPlants4
|
Chlorsulfuron (Telar)
|
$21/ounce
|
Yes
|
Operator ID#
|
Preemergent,
can also be usedas postemergent
|
Spray around the timeof the first rains, a littlebefore or a little afterthe first rains is fine.Spraybefore seedilngs getbig.
|
Check label for plants affected. This herbidiceisspecies specific. Although,itis generally safe on grasses1.
Killsclovers5
|
Clopyralid(Transline)
|
$170/gallon
|
Yes
|
Operator ID#
|
Postemergent
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Spray after all of theweed seed has germinated,but before the plants getbig.
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Kills thistles and legumes,but notgrasses
Killsclovers5
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2, 4-D (DMA4IVM,
Weedar 64and manyothers)
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2, 4-D Amine-
$13/gallon2, 4-D Ester-
$19/gallon
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Yes
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Restricted materialspermit and applicator certificate
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Postemergent
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Spray after all of theweed seed has germinated,but before the plants getbig.
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Kills broadleaves, but not grasses
Killsclovers5
|
Triclopyr(Garlon 3A/Garlon 4Ultra,Remedy Ultra,PathfinderII)
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"Grazing green forage: There are no grazing restrictions for livestock or dairy animals on treated areas...Haying (harvesting ofdried forage): Do not harvest hay for 14 days after application...Slaughter Restrictions: During the season of application, withdrawlivestock from grazing treated grass at least 3 days before slaughter...Livestock Use of Water from Treatment Area: There are no restrictionson livestock consumption of water from the treatmentarea."
Herbicide Label:https://s3-us-west-1.amazonaws.com/www.agrian.com/pdfs/Garlon_3A_Label1i.pdf
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Aminopyralid(Milestone)
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"Grazing and Haying Restrictions: There are no restrictions on grazing or grass hay harvest following application of Milestone atlabeledrates. Cutting hay too soon after spraying weeds will reduce weed control. Wait 14 days after herbicide application to cut grass haytoallow herbicide to work. Do not transfer grazing animals from areas treated with Milestone to areas where sensitive broadleafcrops occur without first allowing 3 days of grazing on an untreated pasture. Otherwise, urine and manure may contain enoughaminopyralidto cause injury to sensitive broadleaf plants...For applications on rangeland and permanent grass pastures (not harvested for hay)andnon-cropland areas, do not enter or allow worker entry into treated areas until sprays have dried...Grazing Poisonous Plants:Herbicideapplication may increase palatability of certain poisonous plants. Do not graze treated areas until poisonous plants are dry andnolonger palatable to livestock...Hay from grass treated with Milestone within the preceding 18-months can only be used on the farmor ranch where the product is applied unless allowed by supplemental labeling." Check label for specific restrictions on moving hay,or using hay for silage,etc.
Herbicide Label:https://s3-us-west-1.amazonaws.com/www.agrian.com/pdfs/Milestone_Label1h.pdf
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Glyphosate (Roundup, Accord XRT II, and others)
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"DOMESTIC ANIMALS: This product is considered to be relatively nontoxic to dogs and other domestic animals; however, ingestionof this product or large amounts of freshly sprayed vegetation may result in temporary gastrointestinal irritation (vomiting, diarrhea,colic, etc.). If such symptoms are observed, provide the animal with plenty of fluids to prevent dehydration. Call a veterinarianifsymptoms persistfor morethan24hours...Donotfeedor grazeturfgrass grownfor seedor sodproductionfor 8weeks followingapplication...If application rates total 4.5 pints per acre or less, no waiting period between treatment and feeding or livestockgrazing is required. If the rate is greater than 4.5 pints per acre, remove domestic livestock before application and wait 8 weeksafter application before grazing orharvesting."
Herbicide Label:https://s3-us-west-1.amazonaws.com/www.agrian.com/pdfs/Roundup_Custom_Label2.pdf
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Chlorsulfuron (Telar)
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"There are no grazing or hay harvest restrictions for any livestock, including lactating animals, with application rates up to 11/3 ounces/acre of TELAR® XP. No exclosure is required for any animals. Do not apply more than 1 1/3 ounces/acre of TELAR® XP peracreper year. No exclosure is required for anyanimals."
Herbicide Label:https://s3-us-west-1.amazonaws.com/www.agrian.com/pdfs/DuPont_Telar_XP_Herbicide_Label5a.pdf
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Clopyralid(Transline)
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"Grazing/Haying: There are no restrictions on grazing or hay harvest following application of Transline at labeled rates exceptfor exported grass hay from California, Nevada, Washington and Oregon (see instructions in the Range and Permanent GrassPasturesection)...Do not transfer livestock from treated grazing areas, or from feeding of treated hay, to sensitive broadleaf cropareaswithout first allowing 3 days of grazing on an untreated pasture (or feeding of untreated hay). If livestock are transferred withinless than 3 days of grazing untreated pasture or eating untreated hay, urine and manure may contain enough clopyralid to cause injuryto sensitive broadleaf plants...For applications to fallow cropland, rangeland, pasture, and non-crop areas, do not enter treatedareasuntil sprays have dried. For early entry to treated areas, wear eye protection, chemical-resistant gloves made of anywaterproof material, long-sleeved shirt, long pants, shoes andsocks."
Herbicide Label:https://s3-us-west-1.amazonaws.com/www.agrian.com/pdfs/Transline1v_Label.pdf
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2, 4-D (DMA4IVM,
Weedar 64and manyothers)
|
"For grazed areas, the maximum use rate is 4.21 pints of DMA 4 IVM (2 lb of acid equivalent) per acre perapplication...Preharvest Interval: Do not apply within 7 days of cutting forage for hay... If grass is to be cut for hay, Agricultural Use Requirements for the Worker Protection Standard areapplicable."
Herbicide Label:https://s3-us-west-1.amazonaws.com/www.agrian.com/pdfs/DMA_4_IVM_Label1d.pdf
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Tables 1 $ 2 from Devii Rao, drorao@ucanr.edu
/table>/table>/table>
starthislte 2
starthistle
Posted on
Monday, August 14, 2017 at
6:13 AM