Training & Stewardship
Picolinic Acid Chemistry (PAC) Training
This Picolinic Acid Chemistry Training covers the application requirements for the use of Invora herbicide for brush and weed management on rangeland sites. Prior to applying Invora herbicide on rangeland, applicators must complete picolinic acid chemistry training every two years.
Texas pesticide applicators can earn 1 CEU in Laws and Regulations with this course.
For more information
// Reach out to us at 1-800-331-2867
// Contact your Invora Herbicide representative below
Undesirable brush and weeds commonly infest rangeland throughout Texas, New Mexico, Oklahoma and Arizona. Some of the most common brush species in this region include several varieties of mesquite Prosopis sp. [honey (P. glandulosa), velvet (P. velutina), western honey (P. glandulosa var. torreyana), etc.] and huisache (Vachellia farnesiana also known as Acacia farnesiana). These and other woody plants interfere with typical ranching and land management operations and:
// Reduce native rangeland and livestock grazing capabilities
// Reduce livestock production profitability
// Consume large quantities of water reducing ground water recharge and availability to desirable plants
// Encroach into wildlife habitat landscapes, displacing desirable forage and browse vegetation
// Negatively impact the native ecological rangeland balance
Invora herbicide is a soluble liquid used for selective weed, invasive species, and brush (woody plants) control on privately-owned NON-HAYED rangeland and NON-HAYED perennial grasslands managed as rangeland in the states of Arizona, New Mexico, Oklahoma and Texas.
Rangelands are those lands on which the vegetation is predominantly native grasses, grass-like plants, forbs, or shrubs suitable for grazing or browsing use. Perennial grasslands are those lands on which the vegetation is dominated by grasses (native or introduced species), grass-like plants, and/or forbs suitable for grazing or browsing use. Rangelands and perennial grasslands would include grazing lands that are not currently managed or intended to be managed for hay or any other agricultural crop including annual forage grasses. Invora herbicide is a tool available to landowners and land managers to combat undesirable brush and weed species.
Restricted Use Pesticide and applicator requirements
Invora herbicide has been registered by US-EPA as a Federally Restricted Use Pesticide (RUP) due to its potential to injure susceptible, non-target plants. Since it is a RUP, Invora herbicide is for retail sale and use only by Certified Applicators or persons under their direct supervision and only those uses covered by the Certified Applicator’s certification. Commercial certified applicators must also ensure that all persons involved in these activities are informed of the precautionary statements.
Prior to applying Invora herbicide, applicators are required to take Picolinic Acid Chemistry training. For information concerning this training and where it is offered visit Applicator Training. Applications must be made by or requested and approved by landowner/land manager. This requirement is to ensure the manager of the land at the time of application understands and accepts the stewardship responsibilities for managing herbaceous vegetation, treated brush material, manure resulting from livestock grazing on the treatment site, and proper clean-out of livestock prior to transport to susceptible crops or off the ranch.
There is no grazing restriction for non-stabled, free-range livestock and dairy animals. Invora herbicide cannot be used on lands where livestock are confined/stabled AND manure is collected. Manure management is a key component to successful stewardship of Invora herbicide. On lands where animals are confined or stabled AND manure is collected, there is a greater risk of manure being moved off-site and potentially entering the compost stream. Restricting use on these sites is to ensure collected manure that traditionally may enter the compost stream or be utilized as a soil amendment for gardens, flower beds, etc. is not contaminated with active ingredients in this product.
Compost industry awareness and Invora Herbicide residue management
Composting is not a new concept; however, this practice has been commercialized into a valuable resource recycling industry throughout our nation in recent decades. A federally supported mission of this industry is a 50% reduction of food wastes entering landfills by 2030. This will lead to major reductions in greenhouse gas emissions and increases in new job opportunities, while recycling critical organics into plant-usable forms.
To accomplish this goal, the industry will continue to expand. As new compost facilities open across the states, hay, straw, grains, manure, etc. from our farms, ranches, livestock show facilities, and sale barns are more likely to enter the compost stream. On the surface this is a good thing, however vegetative materials treated with certain herbicides, or manure from livestock feeding on vegetation treated with certain herbicides may carry enough herbicidal residues to contaminate a facility’s compost. These herbicides break down very slowly in compost, so avoidance of the compost stream is the best course of action. Perhaps the most troubling detail is the contamination usually goes undetected until purchasers of the compost use it in flowerbeds, lawns, gardens, etc.
Invora herbicide (like other similar herbicides in the Range and Pasture market today) is composed of herbicide ingredients that remain active in treated soil and vegetation for a period of time after application. It is imperative that sufficient time is allowed for Invora herbicide to degrade on-site prior to the off-site movement of vegetation or manure.
Bayer values the critically important compost industry and has developed stewardship actions to mitigate risks of Invora herbicide moving into the compost stream. This action includes (1) education, (2) limiting sales to four states, (3) restricting use to non-hayed rangeland sites, (4) restricting use where animals are confined AND manure is collected, and (5) developing a strategy for managing the herbicide residues in vegetation, manure, and treated brush. Stewardship points to protect the compost industry, manage Invora herbicide residues, and limit the liability to Invora herbicide users include:
// Invora herbicide (a premix of aminocyclopyrachlor and triclopyramine) is a restricted use pesticide so only licensed applicators can purchase and apply the product.
// Invora herbicide is restricted from use on sites where vegetation is mechanically harvested and moved off the treatment site (e.g. hay production fields). This has been a common link in many past compost contamination incidences with other persistent auxin-mimicking herbicides (e.g. aminopyralid, clopyralid, and picloram; active ingredients in other commonly used range and pasture herbicides).
// For two years following an Invora herbicide application, herbaceous vegetation (plant residues, grass, leaves, etc.) cannot be removed from the treatment site or used in compost, mulch, or mushroom spawn.
// Brush treated with Invora herbicide must degrade on-site and cannot be removed from the site.
// Invora herbicide cannot be used on sites where livestock are confined AND manure is collected.
// Within two years following an Invora herbicide application, any manure resulting from animals grazing the treated site cannot be removed from the treatment site or used in compost, mulch, or mushroom spawn. Manure and urine from animals consuming vegetation from treatment site may contain enough herbicide active ingredients to cause injury or death to sensitive plants.
// Livestock and dairy animals that graze the treatment site within two years following an Invora herbicide application, must be fed forage not previously treated with Invora herbicide or similar chemistries (including aminopyralid, clopyralid and picloram) for at least three days before transport off the property or being moved to sites other than non-hayed rangeland or non-hayed perennial grasslands. Suggestions for accomplishing this task include 1) only treating a portion of the ranch to allow transfer of livestock to the non-treated rangeland or non-hayed perennial grasslands managed as rangeland for three days, or 2) restrict grazing of the treatment site by confining livestock and providing forage free of Invora herbicide (or similar chemistry) for a period of three days. Any collected manure resulting from consumption of vegetation treated with Invora herbicide should remain in the cleanout area, or be returned to the original treatment site.
Apply in Place and Leave in Place
The Bayer Apply in Place and Leave in Place concept has been developed to protect the compost industry as well as educate landowners, land managers and applicators around responsible use of Invora herbicide.
Buffer Zone Requirements – Property Lines
Invora herbicide can be absorbed through the foliage and root systems of susceptible vegetation. The degree and duration of herbicide activity depends on several factors including the species and its size, the method of uptake (soil versus foliage uptake), soil texture, environmental conditions before, during and after treatment, and the herbicide rate. Certain species may, in particular, be sensitive to low levels of Invora herbicide including but not limited to agricultural crops, conifers (fir, spruce, and pines), deciduous trees (such as aspen, Chinese tallow, cottonwood, honey locust, magnolia, poplar species, redbud, silver maple, and willow species), and ornamental shrubs (such as arborvitae, burning bush, crape myrtle, forsythia, hydrangea, ice plant, magnolia, purple plum and yew).
To help ensure Invora herbicide does not impact vegetation on adjoining properties observe all label use directions, precautions, and restrictions found on the product label including the following:
// Broadcast applications of Invora herbicide cannot be applied within 100 ft of adjacent property lines. A larger buffer zone may be necessary for broadcast applications when sensitive crops are near the application zone or prevailing winds are blowing toward sensitive crops.
// Individual plant treatment (IPT) applications (IPT leaf sprays, cut stump treatments, or basal stem sprays) of Invora herbicide may be made up to the property line.
// DO NOT apply or allow this product to drift onto adjacent properties, sensitive crops, or within the root zone of susceptible trees (note: tree roots on adjacent properties may extend well beyond the property line and into the soil of the treatment site; observe these precautions to avoid impacting trees on adjoining property).
// Internal fence lines can be treated with broadcast or IPT applications.
Buffer Zone Requirements – Water Bodies
Applicators of Invora herbicide must follow all use precautions and restrictions concerning applications around water bodies. Buffer zone requirements differ among the various water body types. Follow label guidelines to ensure optimum water quality for livestock, wildlife, vegetation, down-stream cropping systems, etc.
Areas of temporary surface water:
This product may be applied to terrestrial sites that contain areas of temporary surface water, caused by collection of water in equipment ruts or in other depressions created by management activities.
It is permissible to treat intermittently flooded low lying sites, seasonally dry flood plains, and transitional areas between upland and lowland sites when no water is present.
It is also permissible to treat marshes, swamps, and bogs after water has receded, as well as seasonally dry flood deltas.
Free-flowing water bodies (creeks, streams, rivers, etc.):
DO NOT apply Invora herbicide aerially or ground broadcast within 100 feet of water’s edge.
Individual plant treatment (IPT) applications (IPT leaf sprays, cut stump treatments, or basal stem sprays) of Invora herbicide may be made up to the water’s edge.
DO NOT apply this product directly to or allow this product to drift into water.
Non-free-flowing water bodies (ponds, lakes, etc.):
For non-free flowing, non-irrigation water bodies wholly located on the treatment site, aerial broadcast, ground broadcast, and IPT applications (IPT leaf sprays, cut stump treatments, or basal stem sprays) are permissible up to the water’s edge.
For non-free flowing water bodies used for irrigation and/or NOT wholly located on the treatment site, DO NOT apply Invora herbicide aerially or ground broadcast within 100 ft of water’s edge, but individual plant treatment (IPT) applications (IPT leaf sprays, cut stump treatments, or basal stem sprays) of Invora herbicide may be made up to water’s edge.
DO NOT apply this product directly to or allow this product to drift into water.
Irrigation ditches or canals:
DO NOT apply Invora herbicide aerially or ground broadcast within 100 ft of the outer banks of irrigation ditches or canals.
Individual plant treatment (IPT) applications (IPT leaf sprays, cut stump treatments, or basal stem sprays) of Invora herbicide may be made up to but NOT on the outer banks of dry or water-containing irrigation canals or ditches.
DO NOT apply through any type of irrigation system or contaminate water intended for irrigation.
DO NOT treat or allow spray drift or run-off to fall onto banks or bottoms of irrigation ditches, either dry or water-containing, or other channels that carry irrigation water.
Invora herbicide is registered for use on privately-owned NON-HAYED rangeland and NON-HAYED perennial grasslands managed as rangeland in the states of Arizona, New Mexico, Oklahoma and Texas. Rangelands are those lands on which the vegetation is predominantly native grasses, grass-like plants, forbs, or shrubs suitable for grazing or browsing use. Perennial grasslands are those lands on which the vegetation is dominated by grasses (native or introduced species), grass-like plants, and/or forbs suitable for grazing or browsing use. Rangelands and perennial grasslands would include grazing lands that are not currently managed or intended to be managed for hay or any other agricultural crop including annual forage grasses.
Invora herbicide is not for use on hay production sites or sites intended for haylage, bailage, green-chop or silage. There are other control options available for undesirable vegetation on these sites. Please call your Bayer Vegetation Management, Range and Pasture representative for alternative solutions.
Invora herbicide is for use on privately-owned and operated lands. It can also be used on privatelyowned lands managed through lease or contract agreement provided the following conditions are met:
// The landowner must be notified
// The lease or contract agreement must have at least two years remaining at the time of application. For example; for a five-year lease agreement, apply no later than year three of the agreement, or for a seven-year lease agreement apply no later than year five of the agreement.
These conditions are to allow sufficient time for the land manager at the time of application and for two years thereafter to observe the two-year vegetation and manure management stewardship requirements on the Invora herbicide label.
Brush and weeds controlled by Invora herbicide
Invora herbicide controls a broad spectrum of woody plants and broadleaf weeds. Following are tables documenting known activity of Invora herbicide on various species. Bayer continues to evaluate additional brush and weed species to include in these lists. Non-documented species present on the application site may be impacted by Invora herbicide and should not be sprayed if injury or death of those plants cannot be tolerated.
Brush (Woody Plants) Controlled with Broadcast Applications:
|Lespedeza, sericea||Lespedeza cuneata|
|Mesquite, Honey||Prosopis glandulosa|
|Mesquite, Velvet||Prosopis velutina|
|Mesquite, Western Honey||Prosopis glandulosa var. torreyana|
|Rose, multiflora||Rosa multiflora|
Brush (Woody Plants) Controlled with Foliar IPT Applications:
|Acacia, Catclaw||Acacia greggii|
|Agarito (a.k.a. Algerita)||Mahonia trifoliolata|
|Amargoso (a.k.a. Goat-bush & Allthorn Goatbush)||Castela erecta|
|Granjeno (a.k.a. spiny hackberry)||Celtis pallida|
|Mesquite, Honey||Prosopis glandulosa|
|Mesquite, Western Honey||Prosopis glandulosa var. torreyana|
|Mimosa, Catclaw||Mimosa biuncifera|
|Mountain Laurel, Texas||Sophora secundiflora|
|Persimmon, Common||Diospyros virginiana|
|Persimmon, Texas||Diospyros texana|
|Pricklyash, Lime||Zanthoxylum fagara|
|Rue, African||Peganum harmala|
|Sumac, Flameleaf||Rhus copallina|
|Yaupon||Ilex vomitoria Yucca|
Broadleaf Weeds Controlled With Broadcast or Spot Applications:
|Bindweed, field||Convolvulus arvensis|
|Broomweed, common||Amphiachyris dracunculoides|
|Carrot, wild||Daucus carota|
|Clover, sweet||Melilotus sp|
|Clover, white||Trifolium repens|
|Croton, woolly||Croton capitatus|
|Hemlock, poison||Conium maculatum|
|Ironweed, tall||Vernonia gigantea|
|Knapweed, diffuse||Centaurea diffusa|
|Knapweed, Russian||Rhaponticum repens|
|Knapweed, spotted||Centaurea stoebe|
|Lettuce, prickly||Ambrosia artemisiifolia|
|Lactuca serriola||Marestail (horseweed)|
|Conyza canadensis||Ragweed, common|
|Ragweed, giant||Ambrosia trifida|
|Ragweed, western||Ambrosia psilostachya|
|Sesbania, hemp||Sesbania herbacea|
|Skeletonweed, rush||Chondrilla juncea|
|Sneezeweed, bitter||Helenium amarum|
|Spurge, leafy||Euphorbia esula|
|Starthistle, yellow||Centaurea solstitialis|
|Tansy, common||Tanacetum vulgare|
|Thistle, bull||Cirsium vulgare|
|Thistle, Canada||Cirsium arvense|
|Thistle, musk||Carduus nutans|
Rangeland restoration best management practices – Getting the most out of the application
Timing, foliage conditions and Invora herbicide rate
Application timing is dependent on many factors including the targeted species, environmental conditions, air and soil temperatures and foliage conditions of the targeted species. In general, adequate soil moisture and growing conditions are necessary for a successful Invora herbicide application. Targeted brush foliage should have minimal (less than 25%) damage due to hail, insects or disease. Avoid applications soon after rainfall events and while brush is producing new light green foliage.
For honey mesquite, apply in late spring to midsummer when foliage is mature with a dark green color and after soil temperature reaches 75 degrees F at a depth of 12 inches. For broadcast applications, use Invora herbicide at 24 to 36 fluid ounces per acre with an approved methylated seed oil + organo-silicone (MSOOS) adjuvant (see adjuvant label for rate; typically, four to six fluid ounces per acre).
For huisache, apply in the fall before November 1st. For broadcast applications, use Invora herbicide at 36 to 48 fluid ounces per acre with an approved MSO-OS adjuvant (see adjuvant label for rate; typically, four to six fluid ounces per acre).
Western honey mesquite
For western honey mesquite apply in the late summer to early fall when there is adequate soil moisture. For optimum results make applications once newly developed foliage turns dark green following summer rains (typically 10 days to two weeks after late summer rainfall events). For broadcast applications, use Invora herbicide at 36 to 48 fl uid ounces per acre with an approved MSO-OS adjuvant (see adjuvant label for rate; typically four to six fluid ounces per acre).
Individual plant treatment (IPT) applications
Foliar individual plant treatment sprays
For foliar individual plant leaf sprays (IPT) mix a 1.5% v/v solution of Invora herbicide in water with 0.5% v/v approved methylated seed oil + organo-silicone (MSO-OS) adjuvant. Also include a blue water-soluble dye to mark sprayed plants. Use backpack, ATV-, or UTV-mounted sprayers equipped with a hand-held spray wand tipped with an adjustable conejet X-8 to X-12 nozzle adjusted to deliver a coarse spray. Spray all leaves to glisten, but not to the point of dripping. When targeting honey mesquite, foliar IPT can be sprayed from springtime after soil temperature has reached 75 degrees F at 12 inches deep through July in east and south Texas and through September for other parts of Texas, Oklahoma, and eastern New Mexico. When targeting huisache, foliar IPT can be sprayed from springtime after soil temperature has reached 75 degrees F at 12 inches deep and continued through November.
Individual plant stem sprays (Basal IPT)
For individual plant stem sprays, also known as basal IPT sprays, mix a 15% v/v solution of Invora herbicide in water with 1% v/v approved methylated seed oil + organo-silicone (MSO-OS) adjuvant. Also include a blue water-soluble dye to mark sprayed plants. Use backpack, ATV-, or UTV-mounted sprayers equipped with a hand-held spray wand tipped with an adjustable conejet X-1 or X-2 nozzle adjusted to deliver a coarse spray. Add a 100-mesh spray screen with a check valve to prevent clogging and dripping. Use low pressure, coarse droplets and a narrow cone shaped spray to reduce blow-by of the targeted stem. Hold the spray nozzle within 1 to 2 inches of the mesquite stem. Spray all basal stems, all the way around, to wet but not dripping, from ground line to a height of 12 to 14 inches. Smooth barked plants are more susceptible to this treatment as compared to rough barked plants. Individual plant stem sprays can be applied anytime of the year, although applications made during the growing season are the most effective. Individual plant stem sprays can be applied from springtime after soil temperature has reached 75 degrees F at 12 inches deep through July in east and south Texas and through September for other parts of Texas, Oklahoma, and eastern New Mexico.
Individual plant cut stump sprays
For individual plant cut stump sprays, mix an 6% to 10% v/v solution of Invora herbicide in water with 1% v/v approved methylated seed oil + organo-silicone (MSO-OS) adjuvant. Also include a blue water-soluble dye to mark sprayed stumps. A backpack sprayer is typically the most effi cient method of applying the spray, although spray system equipped-skid steers or -hydraulic shears can be used. When using a backpack sprayer, a X1 or X2 conejet nozzle is recommended. A larger diameter nozzle may be used when mounted on hydraulic shears. Cut mesquite stems level and as close to the soil surface as possible, without getting soil on the cut surface. Hold the spray nozzle within 1 to 2 inches of the cut stump. Use low spray pressure to reduce product waste. Spray to wet, especially the outside edges, but not to the point of runoff. Spray within a few minutes of cutting. Individual plant cut stump treatments can be conducted anytime of the year, but the spray must be applied within a few minutes of cutting the stem.
Land stewardship / Rangeland restoration / Rangeland health
Critical to a successful rangeland restoration program is understanding, “the presence of undesirable brush and weeds is typically symptomatic of a bigger problem.” Invora herbicide is an excellent solution to treat the weed and brush infestation symptom, but there are likely other management issues that must be addressed for long-term treatment success, such as implementing an adequate grazing management program.
Bayer supports the educational efforts of improving rangeland stewardship and soil health of rangeland, etc. from associations like: Grazing Lands Coalitions, USDA/Natural Resources Conservation Service and University Cooperative Extension Systems through Oklahoma, Texas, New Mexico and Arizona, East Foundation, Welder Wildlife Foundation, Noble Foundation, etc. These organizations are highly knowledgeable about proper rangeland stewardship practices, grazing management plans and brush management procedures.
If you have questions concerning best management practices regarding land stewardship, rangeland restoration or rangeland health, please contact your Bayer representative or a representative of one of these organizations. Consider researching your regional Grazing Lands Coalition if you are not already a member.
Understanding brush management outcomes
To make a more thorough evaluation of any brush herbicide treatment, one must consider several factors including long-term brush canopy management, well outside two years after the application. After all, many treatments have excellent results within two years after application.
To evaluate the long-term results of Invora Herbicide compared to commonly applied treatments, researchers examined huisache canopy coverage in fi ve trials sprayed four to six years earlier and honey mesquite canopy coverage in 10 trials sprayed four to ten years earlier. These results indicate the huisache canopy recovered to 30 percent approximately three years after application with commonly used treatments, while Invora herbicide treated plots averaged 2.5 percent huisache canopy cover at three years after treatment. Honey mesquite canopy recovery returned to 25 percent by approximately 8.5 years after treatment with commonly used treatments, while Invora Herbicide treated plots averaged two percent honey mesquite canopy cover at 8.5 years after treatment
Invasive brush (woody plants) can obstruct production of wildlife-beneficial vegetation on native rangelands, however adequate brush cover is necessary to promote healthy, wildlife habitat. Landowners are encouraged to leave a portion of their rangeland untreated to provide adequate cover and/or browse for wildlife. The amount and distribution of brush to leave should be determined by the wildlife species present and/or desired. Before applying brush control practices, landowners are encouraged to consult wildlife biologists with USDA/NRCS, state and county extension offices, state wildlife organizations or other qualified groups for best management practices.
Preparing for use – Animal transportation and clean-out considerations
The landowner/user should consider livestock transportation, movement and clean-out considerations prior to making an Invora herbicide application. Manure and urine from animals consuming vegetation from the treatment site may contain enough aminocyclopyrachlor or tryclopyr to cause injury to sensitive plants. Digestive tracts of livestock consuming vegetation on the treatment site should be voided for three days prior to transporting livestock off the property or moving to sites other than non-hayed rangeland or non-hayed perennial grasslands managed as rangeland, for two years following an Invora herbicide application.
Suggestions for accomplishing this task may include 1) if treatment site is composed of multiple, fenced, land management units consider treating only a portion of those land units to allow transfer of livestock to the non-treated land units [rangeland or non-hayed perennial grassland managed as rangeland] for three days to allow clean-out of the animals prior to transport, or 2) restrict grazing of the treatment site by confi ning livestock and providing forage free of aminocyclopyrachlor or tryclopyr (or similar chemistry such as aminopyralid, clopyralid, or picloram) for a period of three days. Any collected manure resulting from consumption of vegetation treated with Invora herbicide should be left in the clean-out area or spread on the original treatment site and cannot be transported off treatment site.
Personal Protective Equipment – PPE
Applicators and other handlers must wear:
// Long-sleeved shirt and long pants
// Shoes plus socks
// Protective eyewear
// IMPORTANT: When reduced PPE is worn because a closed system is being used, handlers must be provided all PPE specifi ed above for “applicators and other handlers” and have such PPE immediately available for use in an emergency, such as a spill or equipment break-down.
// Follow manufacturer’s instructions for cleaning/maintaining PPE. If no such instructions for washables exist, use detergent and hot water. Keep and wash PPE separately from other laundry. Discard clothes and other absorbent materials that have been drenched or heavily contaminated with this product’s concentrate. Do not reuse them.
ALWAYS READ AND FOLLOW PESTICIDE LABEL DIRECTIONS.
Invora® Herbicide is a RESTRICTED USE PESTICIDE. Prior to spraying, all applicators must complete picolinic acid herbicide training. Bayer Environmental Science, a Division of Bayer CropScience LP, 5000 CentreGreen Way, Suite 400, Cary, NC 27513. For additional product information, call toll-free 1-800-331-2867. www.environmentalscience.bayer.us. Not all products are registered in all states. Bayer, the Bayer Cross and Invora® are registered trademarks of Bayer. ©2022 Bayer CropScience LP.