Restoring Disturbed Rangelands With Site-Specific Seeding

View the project final report

Commodities

Practices

• Animal Production: range improvement, rangeland/pasture management
• Education and Training: on-farm/ranch research
• Natural Resources/Environment: biodiversity, habitat enhancement
• Pest Management: weed ecology
• Soil Management: soil analysis, soil quality/health

An 88% increase in the demand of ruminant meat as a result of changing diets and a projected world population of 9 billion humans (Searchinger et al. 2014), is a direct call to ranchers. This challenge is amplified two-fold because 1) non-native plant invasion decreases rangeland productivity and 2) control is expensive- land owners in Montana spend $4,583 annually controlling non-natives on the average grazing unit (Mangold et al. 2018). Alarmingly, the aggressive non-native annual, cheatgrass, is spreading in south-western Montana. We must create effective management solutions against this plant.

We aim to answer the following: Do non-native plants alter nutrients? Does a novel seed mix out perform a traditional one? Do seed pellets increase establishment success of seed mixes? To answer these questions herbicide (imazapic) will be applied to control cheatgrass in the fall, and restoration seeding in the spring at six sites in the Centennial Valley, MT. The site-specific seed mix composition will be informed by site characteristics and soil nutrients as part of a  greenhouse trial, prior to seeding in the field. The success of seed pellets versus traditional broadcast seeding will be evaluated.

Outreach methods include: field day presentations, academic presentations, and multi-media providing project updates and results. We project the following outcomes: 1) the novel seed mix will have higher establishment and productivity compared to traditional seed mix following herbicide application; and  2) seed pellets will have greater establishment than broadcast seeding.

1. Control cheatgrass infestations using herbicide (imazapic), at water tanks that have been heavily disturbed. Plots will be established in summer 2020 prior to fall herbicide application. Cheatgrass cover will be monitored to assess herbicide efficacy (Summer 2020/21/22).
2. Quantify a site-specific seed mix’s potential to establish, remain productive, and compete with cheatgrass based on site characteristics and soil nutrients. Use site conditions (soil moisture/temperature) and soil nutrients to inform a greenhouse trial of candidate species (winter 2021) to be sown at water tank sites.
3. Evaluate combinations of seed mixes (traditional and site-specific mix) and seeding methods (broadcast and seed pellets) to utilize available soil nutrients, deter cheatgrass and restore productivity at watering tanks post herbicide application. Seeding will occur in spring 2021 based on results from objective 2. Establishment success and biomass production of the seed mixes will be analyzed yearly (summer 2021/22).