As a Result of the Weather...
In our July 2020 post, we talked about the activity we would be doing moving forward into 2020, placing an emphasis on applying day-to-day real-world application of IWM principles to further develop realistic options for producers. For a full re-cap of our planned courses of action, see the “2020 Plans Preview” section of our July 2020 post “Year II Kick-Off.”
Like anything in agriculture, weather plays a commanding role. When we shared the post during the first week of July, our area was doing well weather-wise, with adequate moisture and reasonable temperatures. But that quickly changed. Beginning the middle of July, we experienced hot, dry conditions that continued into the last week of August. Temperatures were well above average and the moisture pretty much shut off. Even though the US Drought Monitor now shows our area as being only “abnormally dry” with moderate drought in regions very close to us, the plants did what Mother Nature designed them to do and quickly slowed in growth. Applying herbicide soon became impractical since the plants would not have taken in much chemical. Planting grass seed would have been a lost cause particularly because of the risk of new plants sprouting only to dry up.
Consequently, we were not able to start any new chemical test plots, nor were we able to test the effectiveness of using cattle to work grass seeds into the ground. We did try to spray some areas prior to the weather bringing everything to a halt and chemically treated the variable-height mowed plots that had been grazed by cattle and some areas within a goat pasture. But this was towards the end of July and the hot, dry weather had already begun to affect how the plants were growing. The chemically-treated chicory did not produce as many flowers as the plants that were not sprayed, but all the plants continued to grow. As of September 2nd, there doesn’t seem to be much difference between the chicory that was sprayed and other plants that were not treated.
We were particularly disappointed in the variable-height test plots. Even after these plots were mowed at the end of the 2019 growing season, then grazed with cattle in 2020, and then chemically treated, the chicory in these plots was able to grow significantly. Again, we did not note many flowers so we will have to evaluate the success or failure of our actions when growing conditions improve.
The true indication of whether the chemical weed control measures were successful or not probably won’t be obvious until next spring when new plants, if any, begin to grow. That is an instance affirming that weed control, even with IWM principles, is not a one-time job. It is a non-stop commitment. That is also a clear example of the IWM rule stressing the importance of using the plant’s physiological characteristics—when the plant is most susceptible to being affected by a control method—to your advantage. We knew the plants’ maturity was getting advanced and being affected by the weather, diminishing the chances for optimum results to happen. But with everything else going on around the farm, things didn’t always work according to a neat schedule. We pushed the time and weather limits. The results, good or bad, will be good information to know.
One of the primary goals of this project has always been to find an effective, sustainable means of controlling the invasive spread of chicory in fields and pastures, retain a sustainable production of the field or pasture, and not remove the desirable legumes such as alfalfa and clover in the process. Even though all of the IWM principles (mechanical, biological, cultural, chemical) have some value and should be used together, as no one technique should be depended upon alone, our research has continually come back to chemical treatment as the most effective, long-term measure to deal with the invasive nature of chicory. As mentioned in earlier posts, some of the SDSU herbicide trials have produced some promising results to control chicory but not eliminate the alfalfa. We are still very much interested in expanding those trials by trying some additional real-world applications to verify the initial results. If successful, we will have accomplished the most significant goal of this research. But those trials simply cannot be completed this year, and we will need to wait for more favorable conditions, perhaps next spring, to continue further.
Initially, we had hoped to conclude our research during the two-year period of this project and be able to provide producers with proven options they could use on their farm or ranch. As our final report (coming in October) will reflect, we can make conclusions about certain aspects of mechanical, biological, and preventative IWM practices. However, as we mentioned and as is typical in chemical and certain features of cultural trials, weather plays a huge role. Beyond heat and moisture, patience is essential to assure recommendations are safe, effective, and valid. All in all, two years simply is not enough time to adequately test and evaluate certain solutions. Even so, we feel confident that we’ll have some promising results to build upon next year. Regarding chemical trials in particular, the first year served to identify which chemicals were quickly effective to control or eliminate the chicory and to evaluate the immediate impact on desirable plants, particularly legumes. This second year provided insight into whether the chicory would be able to rebound and grow back. It also substantiated whether desirable forages impacted the first year could recover during the second growing season or whether they were weakened to the point that they could not regrow. Next year will hopefully solidify those results further.
Chemical IWM Run-Down
This October, when the growing season is complete and we can be more certain of the outcomes, a complete list and the associated results of the fifteen chemicals tested will be published. At this point, we feel safe in reporting that one chemical (Plateau) was found to be completely ineffective for use on chicory, as it had no adverse impacts on the plant. The good news is Plateau had no adverse effect on the alfalfa or clover either. The remaining fourteen chemicals were found to be effective in controlling and/or actually eliminating chicory. However, of those fourteen, eleven impacted the desirable forages to the point that we would not recommend them to control chicory in hay fields or pastures unless there was no concern to also eliminate legumes such as alfalfa and clover.
The final three chemicals produced results that merit further research. These chemicals (Clarity, applied at a rate of 1.5 pints per acre; Garlon 4, applied at 1.5 pints per acre; and Cimarron Plus, applied at 0.5 ounces dry weight per acre) all eliminated the chicory. While they did not leave the red clover unscathed, the alfalfa appeared to recover to an acceptable degree. Clarity and Cimarron Plus appeared to have more of an impact on the alfalfa than Garlon 4. But, the results in the Garlon 4 plots definitely show great promise to remove chicory from hay fields without causing an unacceptable loss of alfalfa. These three chemicals will be the subject of further testing next year.
It MUST be emphasized that the alfalfa in the test plots is “old,” at least 20 years old. It is uncertain what effect any of the chemicals would have on newly planted (within 5 years or less) alfalfa. Therefore, the results we are mentioning for the purpose of this project must be cautiously applied to newer stands of alfalfa.
Other 2020 Happenings
On a couple of other notes we reported in July, we had been conducting other routine IWM practices on our farm as part of our normal operation and have identified a potential problem with Deptford Pink (scientific name, Dianthus Armeria). South Dakota State University Weed Science Department (the same people conducting the chicory trials) was able to begin research on July 15th of this year on controlling the Deptford Pink in one field that suddenly became heavily infested with the plant. Fourteen chemicals are being tested in a total of 60 plots.
Little seems to be known about this potentially invasive plant so we are starting with limited information. We have been able to determine so far that Deptford Pink is a biennial that reproduces from seed only. A plant develops the first year without a flowering stalk. Then, during the second year, it bolts to form the flowering stem. Our research has failed to prove conclusively what a first-year plant looks like. We believe it is a small rosette type of plant but we are not certain. This information is determined from the fact that Deptford Pink is a member of the dianthus family and other dianthus plants form rosettes at the beginning. The overwhelming majority of the plant photos on the internet show the second-year plant only.
What has became apparent is that Deptford Pink appears to mature in hot, dry weather. The plots were chemically treated on July 15th and within 15 days, all of the plants turned brown. However, this was not necessarily the result of the chemicals, as all the plants, treated and untreated, within the test plots and outside of the testing area all look the same.
So, unfortunately, any observations of obvious impact on the standing plants from the chemical treatments is completely unreliable. Using the presumption that the first-year plant begins as a rosette, we examined the ground level of the test plots to determine if the chemical treatment had any effect on the young, first-year rosettes. Small rosettes were found and we noted some of the chemicals had a definite impact on the rosettes and some did not.
We are also conducting germination tests on seeds collected from the test plots to determine if the chemical treatments had any effect on the viability of the seeds. There are no results to report as of the date of this post.
Again, observations made next spring will likely be a key indicator as to whether any chemical treatments were effective or not and whether chemicals are at all useful in controlling Deptford Pink. This plant could potentially create a major problem. Stay tuned for more developments on this project.
Finally, a note of caution to anyone who uses goats to graze pastures. It is common knowledge that goats are browsers and prefer to eat woody plants. We have owned goats for ten years. We know that they eat pine needles and small branches on trees. What we didn’t realize is that they will also eat the bark and chew through the bark to the inner fiber layers of the trees. If the goats are able to completely girdle a tree, they can potentially kill it, even a large pine tree. We have had to resort to covering the trees in one pasture with plastic snow fence to keep the goats from destroying the pine trees. Goats may not actually eat everything, but sometimes they eat enough to be a problem. Just a word to the wise.
Stay tuned for our final report in October. Until then, if you haven’t already signed up for our newsletter on our website or Facebook page, we invite you to do so by following this link. See you next month!
Year II Kick-Off
Welcome to year two of our SARE-funded research project to evaluate the effectiveness of Integrated Weed Management practices to control the invasive spread of chicory. The fact that this post didn’t come out earlier this spring doesn’t mean nothing has been happening. On the contrary, a lot has been going on. The emphasis this year has changed a bit from last year. In 2019, many initial steps of the research project were taking place. This year, we are monitoring and continuing to study and evaluate the results of efforts taken last year. Now that the growing season is in full swing, the next steps in the project can begin in earnest.
Before we provide a quick recap of 2019, here is a brief review of the five principles of Integrated Weed Management (IWM). IWM is a process that applies the following techniques: mechanical (mowing, cultivation, tillage, hand-pulling), chemical (herbicides), cultural (cover crops, crop rotation), biological (grazing animals, beneficial insects), and preventative (curtailing the spread of undesirable seeds), combined to control and/or eradicate problematic weeds over the course of a growing season. The key to IWM is not relying too heavily on one method. Sequentially applying as many of the IWM principles as possible often assures greater success.
Often downplayed but vitally important in a successful weed management program, and critical before implementing IWM actions, is the necessity of looking for and selecting specific weed species to target. Once that is done, it’s also a good idea to research the physiology of the targeted plant to learn what makes it tick. This makes it possible to adjust the timing of control methods and resources to match when the plant is most vulnerable, which increases the chances for success. Applying control or eradication actions at the wrong time can lead to less than desirable results.
We had some successes and failures during the 2019 research period. Some results, as is true with any research, will take more time to evaluate. For a detailed summary of 2019’s results, refer to the “End of Year 1 Review” report from November of last year. That post also outlines possible directions we were, at the time, planning for 2020. While some slight modifications will be made to those ideas, the objectives outlined at the end of 2019 are still valid.
Among the goals of the chemical (herbicide) trials was the goal to identify which chemical(s), if any, effectively controlled chicory but were safe to use on alfalfa and legumes in our farm’s pastures and hay fields. At end of 2019, we had no conclusive results to indicate potential chemical options. However, a couple of chemical plots showed some early, promising signs. As reported below, our 2020 observations are making it clear that the one sure-fire method to control and eradicate chicory is through the use of herbicides. However, we still want to ensure that legumes, and the overall quality of forage, won’t suffer, so our 2020 efforts are going to be critical.
One hurdle that needs to be crossed with any weed-control program, whether it be conventional or organic, is whether the practice is possible of a long-period of time—is it sustainable? Unfortunately, not many organic methods developed in 2019 seemed promising. This is especially true of organic methods related to our semi-arid pasture lands and hay fields. The topic of sustainability was covered in the September 2019 post “The Question of Sustainability.” In short, a “sustainable” agriculture operation must be economically viable over the long-term, the operator must practice ecologically responsible stewardship of their resources, and the operation must provide a desirable quality of life for its operator and supporting community. One aspect without the others may result in short-term survivability. But without all three sustainable characteristics, a long-lasting operation will undoubtedly fail.
If the farm/ranch operator is a “hobbyist,” losing money isn’t so damaging and labor-intensive practices may be tolerable for a short time. But when a farm/ranch owner must consider the needs of the operation year after year, the vision is dramatically different.
From the organic approach, large scale use of organic chemical methods (vinegar or alcohol) were simply not practical. Those options may work in a small garden but not on a 20-40-160-acre field. Repeated mowing of the chicory (and the associated desirable plant community) may keep the weed from flowering and producing seed, but yield and forage quality will ultimately suffer. Many successful organic producers are able to use mechanical, tillage methods—often repeated several times throughout the growing season—to keep the weeds at bay in their crops. But tillage simply isn’t an option in pastures or in areas where it isn’t realistic to replant hay fields every year.
In our conversations last year with one particular organic producer from outside of our area, he emphasized the need of the organic farmer to get weeds under control before moving to organic production. He explained that it may be necessary to start out with chemicals and, once the weeds are manageable, convert to organic practices. This particular producer uses conventional tillage (plowing and other methods), but, again, this is not possible on pastures. He also emphasized that if a producer finds themselves in a situation where the weeds are taking over, it may be necessary to step away from being organic on a particular field, use conventional methods (chemicals) to regain control of the weeds, and then reapply for organic status.
As a result of last year’s observations, our project in 2020, while continuing to conduct trials using IWM that certainly apply to organic operations (mechanical, biological, cultural, and preventive), will not be focusing any further on finding a strictly organic solution to control chicory in our pastures and hay fields.
Early 2020 Observations
In the first week of February, while there was still snow on the ground, we noted that the chicory had already began sprouting from existing plants. We noted a similar situation last year. This proves that even if the old plants appear to be “dead” above ground, problems lurk below the surface. This is why, for effective weed control, it’s advisable to use a chemical with a residual, pre-emergent element to kill young weeds as they sprout. This can be devastating, however, to other plants (such as legumes) that can also be killed by the pre-emergent chemical. Another technique often used to control weeds at their early growth stage while minimizing damage to desirable plants is to spray early-sprouting weeds with a herbicide (preferably, glyphosate because it does NOT have a residual component). This process kills the early weeds before the other plants that are also susceptible to the chemical grow enough to be affected. But this is risky and, generally, with snow on the ground, even the chicory isn’t actively growing to the extent that any herbicide will be completely effective.
At the end of March, we checked the plots in which, in 2019, we had tested mowing chicory at variable rates (4”, 6”, 8”, and 10” heights) to determine if there was any difference in the degree of control due to more or less residual matter being left on the ground. Observations indicated the mowing height made no difference and, as was observed in February, the young plants were actively growing in all plots. The only difference to mowing at higher heights (8”and 10”) is some forage was available for livestock.
We checked these mowed test plots again in mid-May with more obvious results showing that the chicory was even more actively recovering from the mowing.
Therefore, in these plots, mowing alone may have reduced the seed population of the chicory, but it certainly did nothing to eradicate the plant. As a reminder, during research to put our project’s proposal together, we learned that chicory is theoretically an annual/biannual plant, meaning that a plant should live for two years. However, research also found that chicory may live for five to seven years if the conditions are good. Our experience has been that mowing repeatedly over several years has had no apparent reduction in the chicory population and, in fact, stimulates its growth. The research from the test plots so far only bolsters our previous observations, thus leading us to conclude that mowing alone is not an effective control (and certainly not an eradication measure), regardless of the height the plants are being cut. For more details on what we learned early on about mowing chicory in our 2019 research, check out the “Mechanical IWM” section of our June 2019 post “IWM Underway.” The studies we found dealt with cultivated chicory, and at the time, we wondered if wild chicory would react the same as its tame cousin. Our observations lead us to believe the wild plant does respond the same.
In May, we also studied the herbicide test plots to ascertain whether any early conclusions, differing from 2019 observations, could be made. In 2019, most of the herbicides were effective in removing the chicory, but many or most also appeared to have eradicated the alfalfa and clover. The one exception, as noted in our September 2019 post “Recording Results,” was the chemical Plateau, which we learned is designed to be ineffective in controlling chicory. As for any clearer indications of chemical results, it was still too early in May to make conclusions.
In June, we surmised even more that mechanical measures to control chicory (i.e. mowing) are, at best, stopgap control measures to keep the plants from seeding out. These efforts are totally ineffective in achieving total, long-term control and certainly will not lead to eradication of the chicory plants.
With regard to our biological practices, grazing by our goats shows evidence that animals are nipping tops of stems as the plants bolt (form the flowering stem). As in 2019, however, we see no indication that they are reducing the plant’s nutrition sources. We had previously learned that the leaves taste bitter so we are not surprised. The grazing behavior we are seeing is indicative of goats’ preference to eat plants at shoulder height and not ground level. As with the mowing, their grazing will control flowering but we are not seeing any sign that the population of the chicory is being reduced.
As we’ve re-examined the herbicide plots in June, we see that, in many of the test plots, the alfalfa is recovering and the chicory appears to have been eliminated. This could potentially be a result that the alfalfa in these plots is “old” alfalfa, several years old with deep roots. Because of the root structure, the plants may have “staying power.” This fact could be used to our advantage. However, we would caution applying our results from this project to fields containing young alfalfa and clover plants, as the roots will likely not be as deep. Because the herbicide trials are being officially conducted by the South Dakota State University (SDSU) Weed Science Department, we are not releasing any conclusions until their research is finalized. We will, however, continue to provide updates as to whether any chemicals reveal any candidates that may meet our goal of eradicating the chicory plants but retaining the legumes in our hay fields.
2020 Plans Preview
Now that we know the strengths and weaknesses of each IWM method, when used individually, our actions this year will reflect a more non-research, day-to-day practical application of IWM to develop options for producers.
First, we will be applying herbicide to the variable-height mowing areas to prevent chicory from spreading further in the pasture containing the test plots. Because repeated mowing alone has little negative impact on the chicory, we currently have cattle grazing that pasture. They have not consumed the chicory, but we are noticing some impact on the plants. Depending on the condition of the plants once the cattle are moved, we anticipate mechanically mowing the area to further damage the chicory. We will then apply herbicide while the chicory is actively recovering to determine its eradication rate.
Second, we may repeat some chemical trials on new plots within the pasture being grazed by our goats. These pastures contain clover and alfalfa, so we plan to test those chemicals that show potential of eliminating the chicory but not completely removing the legumes. We would like to test whether or not grazing will weaken the chicory plants enough so that we may be able to use a lower rate of chemical.
Third, we would like to improve a certain hay field that has historically been a poor producer due to a high water table stunting the grass varieties present. We have been applying chemical to the field because of chicory infestations, thereby removing all legumes, and we are going to attempt to change the plant population and diversity of the field (an IWM cultural approach). The field is not a good candidate for conventional tillage due to the water table. We also do not have a no-till drill and, while we could rent one, we are trying to find other ways to plant grass seed using livestock. We will be studying the effect of using cattle to graze the area concurrently with introducing grasses that are more moisture-loving to determine whether the hoof action of the cattle duplicates the action of a no-till drill. This process will be weather-dependent. We may try it yet in July if the moisture conditions are favorable. If conditions are not satisfactory, we will perform this experiment in the fall when we typically get autumn moisture.
Finally, we have been conducting other routine IWM practices on our farm as part of our normal operation. Through these efforts, we have noted a “new” plant that appears to be taking hold in one particular hay field. Through reading and research, we have identified the plant as Deptford Pink (scientific name Dianthus Armeria). This plant is relatively unknown in South Dakota. Many other areas of the country have noted its presence but little is published about the plant or its possible impact on fields and pastures. It is not a noxious weed at this time, although some have noted that it can be invasive. Because we are already cooperatively working with the SDSU Weed Science Department on the chicory plots, we will be conferring with them on treatment options.
That is all for now! If you haven’t already signed up for our newsletter on our website or Facebook page, we invite you to do so by following this link. See you next month!
End of Year I Review
Now that we have the first year of our two-year SARE/SDSU Integrated Weed Management (IWM) project under our belt, we can reflect on what we learned, what worked, what didn’t, and what we plan to do next year. While we learned many things, we would like to summarize for you the three key lessons we realized. Using those examples, we would also like to outline some of the main objectives for next year’s project activity.
(If you want more information on the points made here, you can read the individual blogs that covered the information in more detail.)
The all-encompassing thought that clearly stood out at the end of this year was the fact that, after many years of working our farm—raising crops, grazing livestock, and working to control unwanted weeds—we really thought we knew the basic principles of IWM. That may have been somewhat true. But we now realize that we didn’t truly comprehend the total IWM package, that is, how the five individual principles work together and, more importantly, how they need to be used together.
One of the crucial first-steps in implementing IWM into any operation is doing an assessment of the weed problem. In our mid-May blog (“The FAQs of IWM”), we explained how the assessment process is accomplished. At the end of our first year of research, we realized that this first step is far more crucial than just checking the box to say it is done. The act of assessing is an ongoing process. We’re doing that but, in reality, we could be doing more, with regard to really studying the problem, reading about what other growers have experienced, and fully studying others’ research.
When it comes to controlling chicory, as with any plant, it has certain physiological characteristics. Certain things make it grow or fail to thrive. This year, we found spraying the plant too early or too late can have the same result, as in a poor result. We also found that using goats and cattle to graze the plant too young may yield poor results. The taste of the young leaves may be too bitter to attract the livestock. It may be difficult to encourage them to eat the weed instead of the tender, early-growth grasses or more tasty plants. Waiting until the chicory plant bolts (develops a stem) may actually provide a better chance of controlling it.
One thing that agricultural producers (and other plant-growing professionals) know when using herbicides is to read the chemical’s label information, that multi-page document typically glued to the herbicide container that has no shortage of small print, text and charts. It isn’t light reading, but it’s important material. We learned that when we found one chemical in our herbicide trial that didn’t have any effect on the chicory. As noted in our mid-September blog (“Recording Results”), we found it important to not only study the safety precautions and application rates but to look at the chemical makeup as well. This was a simple lesson to remind us that herbicides are plant specific. One must take the time to fully read the instructions.
Each of the five IWM practices (mechanical, chemical, cultural, biological, and preventative) has its benefits and short comings. Our experience from this past year’s research intentionally focused on each distinct IWM element in an attempt to gain a deeper understanding of each of those elements and to find what does and doesn’t work. That goal was a success; we now understand more fully the pros and cons of each IWM element. The successes and failures are highlighted in our previous blog posts from this year. We will use those lessons to move forward into next year, particularly as we expand our efforts to a more comprehensive research process.
Along with the objectives of the goal mentioned above, we tried to find weed management options for both conventional and organic producers. We found that conventional methods, those practices that incorporate chemical options into their programs, had more tools that could be used. We knew that. We also knew there would be more challenges for an organic grower, particularly if they didn’t want to use chemicals and wanted to avoid tillage, a basic means to control weeds in many organic operations. At the end of this year, it was even clearer to us that organic operations face some serious challenges. We have some ideas for next year; more on this later.
Our third lesson was we found there are objectives and goals that go beyond just controlling an unwanted weed. The overall health of an agricultural operation involves more than removing a noxious plant. Things such as soil health, ground cover, field production, profitability, and the producer’s quality of life also need consideration. In our end-September blog (“The Question of Sustainability”), we addressed these concepts. It likely will benefit us to review that information from time to time, as it’ll help keep us focused on why we are doing what we are doing.
Moving Forward into