Temperatures are starting to cool down a bit, a nice reprieve from the consistently hot summer we've been having. Maybe we'll get some rain in the next three or four weeks and get some good germination. Hopefully, we won't get too much yellow starthistle this coming year, but we'll see. One of the things that ranchers most often ask me about is how to control yellow starthistle. So start thinking about your management options now! Weed Control in Natural Areas in the Western United States (DiTomaso, Kyser, et al. 2013) is an excellent book with information on how to control yellow starthistle and many other invasive species that occur in California. If you go to Google and type in UC Weed Report plus the name of the weed you are interested in you should get the section from this book on that particular weed, assuming the weed is included in the book. The yellow starthistle section is available at http://wric.ucdavis.edu/information/natural%20areas/wr_C/Centaurea_solstitialis.pdf. This article summarizes the yellow section chapter from the DiTomaso, Kyser, et al. book.
Three of the main yellow starthistle control strategies are herbicide, grazing, and mowing.
Herbicides: Several herbicides are effective on yellow starthistle, but two of the best options are Aminopyralid (Milestone) and Clopyralid (Transline). The best time to spray Aminopyralid is from the seedling stage to the rosette stage. The best time to spray Clopyralid is when the plant is in the late rosette stage. Grasses are not harmed by either herbicide.
Grazing: Cattle, sheep, and goats can all be used to graze yellow starthistle. The best time to graze is from the bolting stage to right before the spiny heads emerge. Bolting is the stage after the stem comes up out of the rosette, but before the flower head begins to emerge. Protein content during this stage is relatively high: 8% to 14%. Once the spines come out yellow starthistle becomes less attractive to cattle and sheep and they start avoiding it. Goats, on the other hand, are not dissuaded by the spines so they are often used in yellow starthistle targeted grazing programs. Short-duration, high-intensity grazing is the most effective grazing strategy to control yellow starthistle.
Mowing: Mowing can be an effective control option if you have an area that's flat enough for a mower to be safe and not tip over and doesn't have too many big rocks to get in the way of the mower. It will take several years of mowing to control yellow starthistle. Control will be even better if mowing is used in conjunction with other control methods. The best time to mow is when 2%-5% of all the yellow starthistle plants are flowering. Timing of mowing is critical. If you mow too early, yellow starthistle can grow back and produce even more seed than if you had not mowed. Mowing too early will also eliminate grasses and other existing plants that were competing with yellow starthistle. Yellow starthistle doesn't do as well if there's a thick mat of other vegetation to compete with. So, removing these plants releases yellow starthistle from competition, allowing it to grow better. If you mow too late, you'll spread the seed. Researchers found that they got the best results when they mowed twice: once during the early flowering stage and then a second time 4-6 weeks later after the plants had regrown and had produced flower buds.
Effectiveness of mowing also depends on how your yellow starthistle plants are growing. If you have plants that are tall and the branches are high up on the plants, you may only have to mow once during the early flowering stage. But, if you have plants that are spread out at the base and the branches are lower on the plant, you may not be able to control it very well because the mower can't get low enough to cut the branches.
Have you been successful controlling yellow starthistle on your ranch? If so, make a comment on this blog and let us know how you did it!
DiTomaso, J.M., G.B. Kyser et al. 2013. Weed Control in Natural Areas in the Western United
States. Weed Research and Information Center, University of California. 544 pp.
DiTomaso, J.M, G. B. Kyser, and M. J. Pitcairn. 2006. Yellow starthistle management guide. Cal-IPC
Publication 2006-03. California Invasive Plant Council: Berkeley, CA. 78 pp. Available: www.cal-ipc.org.
Dr. Jeff Stott, UC Cooperative Extension Professor of Pathology, Microbiology & Immunology at UC Davis, recently gave a talk on foothill abortion at a producer meeting in San Luis Obispo County. Click this link to see his PowerPoint presentation: http://cesanluisobispo.ucanr.edu/files/267719.pdf. For those of you who were not able to attend, I summarized some great information from his talk below.
Signs of Foothill Abortion
The foothill abortion bacterium can cause fetal mortality. The bacteria live in the uterus for 30-40 days. So, if you breed animal during that time, 3-4 months later she'll abort, cycle back and re-breed. The bacterium can also cause term abortions or weak calves. Heifers and cows are susceptible to foothill abortion if they get bit 30 days prior to conception to 150 days after conception. If they are exposed before or after this time they will probably not be affected. If an animal is infected as late as 5 months into gestation, she will likely give birth, but her calf will be weak.
Ranchers can lose up to 90% of their calf crop when unexposed cows are brought into a new area and are exposed to the tick for the first time.
You can vaccinate calves as soon as you know you're going to keep them as replacement heifers. But, the foothill abortion vaccine should not be given to pregnant females or those who will be bred within 60 days after vaccination. Animals vaccinated during that time period may lose the fetus.
There have been no reports of anaphylaxis, illness, or death associated with the vaccine. The foothill abortion vaccine can be administered at the same time as the brucellosis vaccine without causing any apparent problems. Some skin reactions have been observed, however. These include swelling at the injection site around 21-56 days after vaccination. The swelling is actually related to an immune response, likely the live bacteria at the injection site still active from the vaccine, which are acting as a “booster shot.”
Foothill abortion has only been documented in California, Nevada, and Oregon, so it has been difficult to get a company to produce the vaccine. However, cattlemen in foothill abortion areas have been vocal for a long time and because of that we are now getting closer to having a vaccine commercially available.
This is the twice-a-year meeting of the Central Coast Rangeland Coalition. The goal of this meeting is to improve economic security for livestock operators on the Central Coast by preventing livestock-carnivore conflict and providing potential resources when they do occur. For more information or to register click here.
Date: Thursday, October 19, 2017
Time: 8:30 AM - 4:00 PM
Location: Midpeninsula Regional Open Space District, 4150 Sears Ranch Rd, La Honda, CA 94020
Cost: $35.00, includes lunch
Registration Deadline: Thu, Oct 5, 2017
The goal of this meeting will be to improve understanding of tools for increasing livestock safety and carnivore tolerance on California's central coast rangelands -- from the perspectives of ranchers, agencies, and other rangeland owners. We will explore how techniques are applied to prevent depredations as well as methods for increasing economic viability of ranching alongside carnivores, including agency policies for compensation. Meeting presenters and participants will discuss animal husbandry practices, as well as hear from practitioners involved with local wildlife compensation programs.
Improve economic security for livestock operators on the Central Coast by preventing livestock-carnivore conflict and providing potential resources when they do occur.
- Improve understanding of tools and approaches that Central Coast ranchers and land managers can apply to reduce carnivore-livestock interactions
- Provide an introduction to a local depredation compensation program for losses when they occur
- Foster productive discussion of these topics
Bridger Feuz is an economist and showed us a few different online tools ranchers can use to help make decisions about their operations. Some of the tools on his website are the Partial Budget, Break-Even Budget, Cow Valuation, Genetic Investment, Stocking, and AUM Value tools. Here's the link to Bridger's website with all the tools: http://uwyoextension.org/ranchtools/. One of the tools he demonstrated for us was the Partial Budget tool. This tool can be used if you are thinking about making a change to your operation and you're trying to figure out if that change will increase or decrease your income. The tool is simple to use and asks four questions.
Based on the proposed change:
1) What new or additional costs will be incurred?
2) What current income will be lost or reduced?
3) What new or additional income will be received?
4) What current costs will be reduced or eliminated?
The example Bridger used in his presentation was, should you sell 100 steer calves at 500 pounds in the fall like you normally do or would it be a better financial decision to change your strategy and keep the 100 steers through the winter and sell them the following fall at 900 pounds. Remember this is an example from Wyoming and doesn't necessarily match the production cycle here on California's Central Coast, but the tool can be used for any type of proposed change to your operation.
For this example, new or additional costs would include the need for more feed and grass, more vet bills, and transportation of the 900 pound steers. Current income that would be lost is the price you would have received for selling the 500 pound calves this year. The new or additional income would be the price you receive from selling the 900 pound steers the following year. The current costs that would be reduced or eliminated would be transportation of the 500 pound calves. Once you put all of this information in the online tool, which is basically like a calculator, it will give you a number showing what your net income or net loss would be based on making this change.
If you're curious about the Partial Budget tool and want to give it a try, go to http://uwyoextension.org/ranchtools/partial-budget/.
Here's a link to the fact sheet on how to use the Partial Budget tool: http://uwyoextension.org/ranchtools/wp-content/uploads/2012/09/partial_budget.pdf.
If you have questions about this tool you can reach Bridger Feuz at (307) 783-0570 or BMFeuz@uwyo.edu. For questions about the BCS handout, contact Hudson Hill at (307) 885-3132 or firstname.lastname@example.org.
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. Both tables are attached as PDFs at the bottom of this blog post. 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.
Carbonaro, D. 2017. Personal communication, 4/16/2017. Carbonaro is a Senior Biologist/Inspector with the San Benito County Agricultural Commissioner's Office.