Rejuvra® Herbicide Stewardship Guide for Restoration and Protection of Desirable Vegetation in Rangeland, CRP and Natural Areas
Invasive annual grass species such as cheatgrass (Bromus tectorum), medusahead (Taeniatherum caput-medusae), ventenata (Ventenata dubia) and red brome (Bromus rubens) are changing western rangeland and natural areas in a cycle that favors their spread at the expense of desirable vegetation.
They compete with desirable grasses, forbs and shrubs by germinating in late-summer and winter, continuing root development over winter, starting rapid above ground growth in late-winter and stealing moisture and nutrients before desirable perennials start to grow in spring. The invasive annual grasses out-compete the desirable perennial plants and significantly reduce their growth.
// Every year after the annual grasses mature and produce seed, they turn brown and die in late spring into summer. The new seed production is added to the soil seed bank and the dry foliage is added to the thatch layer.
// The thatch layer creates a continuous bed of flammable fine fuel that increases wildfire frequency. Desirable perennial species can be killed or never have a chance to fully recover because of the increased fire frequency. In addition, the wildfires are a threat to humans, wildlife, property and infrastructure. Ranchers are particularly vulnerable because they lose standing forage, livestock, fences, structures and access to grazing lands.
// Invasive annual grasses have minimal forage value or are only optimal for grazing over a very short window. The awns are irritating resulting in livestock avoiding areas with even relatively low levels of annual grass invasion. The invasive annual grasses repeatedly steal moisture and nutrients that would otherwise be used by desirable forage species. The result is reduced forage quantity and quality for livestock and wildlife.
// Wildlife species such as the sage grouse and desert tortoise are at risk because of the dramatic increase in invasive annual grass dominated rangelands and natural areas.
Long-term Control
Trial work across the western US documented that Rejuvra is a highly effective tool for control of many invasive annual grasses. While other products are available for annual grass control, they are inconsistent or only provide a relatively short duration of control. Annual grass seed can remain viable in the soil and thatch layer for many years and other products do not provide adequate residual control to address the total number of viable seeds, known as the seed bank. A single application of Rejuvra can prevent germination of annual grasses for multiple years. This provides ranchers and land managers with a new opportunity to start the process of depleting the annual grass seed bank. Restoration activities such as reseeding and replanting are expensive and difficult. The best time to control invasive annual grasses is when viable populations of desirable perennials are present. Prioritize invasive annual grass control on sites that still have viable populations of desirable perennials.
Long-term control with Rejuvra® herbicide results in:
// Invasive annual grass soil seed bank depletion
// Increased forage production
// Decreased fine-fuels associated with wildfires
// Restored native plant communities
// Increased wildlife habitat quality
// Improved pollinator habitat
Label
Rejuvra is labeled for the restoration and protection of Rangeland, Conservation Reserve Program (CRP) lands, Natural Areas e.g. Parks and Open Space, Wildlife Management Areas, Recreational Areas, Fire Rehabilitation Areas, Prairies and Fire Breaks and any of these sites that are grazed or cut for hay. Rejuvra is pending registration in the states indicated above.
Controls invasive annual grasses
// Annual Bromus species including
// Cheatgrass / downy brome (Bromus tectorum)
// Cheat (Bromus secalinus)
// Japanese brome (Bromus japonicus)
// Red brome / foxtail brome (Bromus rubens)
// Medusahead (Taeniatherum caput-medusae)
// Ventenata (Ventenata dubia)
// Feral rye* (Secale cereale)
// Jointed goatgrass (Egilops cylindrica)
// Bulbous bluegrass (bulblettes)
* Suppression
Broadleaf Biennial and Perennial Weed Control From Seed
// Dalmation toadflax
// Common mullein
// Diffuse knapweed
Livestock Grazing
There are no label restrictions on grazing. This means that livestock are permitted to graze immediately after application. However, allowing livestock to graze soon after application is not recommended. Heavy grazing after application and before enough rainfall occurs to move the herbicide to the soil can result in re-distribution of the applied Rejuvra. This can lead to reduced weed control. Grazing animals show a strong preference for treated areas free of annual grasses. Intensive grazing on newly released perennial grasses can prevent or delay recovery.
Grazing injury will be exacerbated if only small areas are treated resulting in a high concentration of grazing animals. Small perennial grasses can be uprooted by grazing animals. Allow time for small perennial grasses to establish before grazing.
Haying
Areas can be cut for grass hay starting at 40 days after Rejuvra application. Rejuvra has not been tested in areas intensively managed for grass hay production and is not intended for use on these areas. This includes, but is not limited to,intensively managed grass production pastures with species such as timothy (Phleum pratense), fescues (Festuca species), blue grasses (Poa species such as Kentucky bluegrass) and perennial ryegrass (Lolium perenne). Hay from treated areas cannot be exported.
Application Timing
Rejuvra provides pre-germination control of seedlings by disrupting and inhibiting normal root growth as the root tries to emerge from the seed. In general, Rejuvra has no post-germination activity meaning that it does not control plants after they have established the first root.
// For control of annuals, Rejuvra must be applied before they germinate.
// In order to provide pre-germination control of annuals, Rejuvra must first be activated by rainfall.
// Many herbicides are degraded quickly by sunlight if they lie on the soil surface before rainfall allows them to bind with soil particles. In contrast, Rejuvra has good photo stability, meaning minimal breakdown on the soil surface as a result of exposure to sunlight. This allows some flexibility in application timing relative to rainfall.
// Rejuvra should be applied with an expectation of precipitation within two months after application.
// To increase the chance of activating rainfall before annual grass germination, a minimum time of one month between application and first expected germination of annual grasses is recommended.
