Rejuvenation of Saline Soils with Saline Tolerant Forages
Funded by Results Driven Agriculture Research
In collaboration with the University of Saskatchewan
Soil salinity limits plant growth and lowers crop yields by restricting root uptake of water and nutrients. Many livestock producers have observed soil salinity issues on their pastures and hayfields during recent growing seasons. According to a Government of Alberta report published in 2020, more than 600,000 acres of land had soil salinity severe enough to reduce yield potential to zero (GoA, 2020). This represents a direct cost to the landowner and to agriculture, as these areas generate no economic return.
These acres may benefit from reclamation with saline-tolerant forages, enabling them to be returned to a higher productivity state in the future. Forage breeders at the University of Saskatchewan Crop Development Centre recently released a salt-tolerant hybrid wheatgrass, which this on-farm study evaluates for its suitability on saline soils in the Peace Region.
What We Did
The 4-year project, which began in 2024 with the establishment of forages, was conducted in Brownvale, within the Municipal District of Peace. The site met the required conditions (electrical conductivity [EC] > 4 dS/m) for conducting the trial. Table 1 presents the site history, field operations performed, and data collected in 2024 and 2025. The experimental design employed a randomized complete block design with four replications in small plots measuring 8 m x 1.8 m. Five (5) perennial forage treatments were evaluated, each comprising a blend of 2-4 forages (see Table 1 for the list of forages). Seeding of the forages was carried out using a 6-row Fabro plot drill equipped with disc-type openers on 23 cm row spacing, complete with mid-row fertilizer banding.
The weather conditions for the growing season at the project site in the establishment year (2024) are shown in Figure 1. The growing season received above-average precipitation of 12.6" with an average temperature of 12.5°C and 1294 growing degree days.
Field Notes
Visual stand estimation 30 days after seeding indicated patchy establishment of all seeded forages (see pictures below), with some notable visible Alfalfa seedlings (Figure 4a). In early spring of 2025, the plots benefited from early spring moisture and produced luxuriant forage growth (Figure 4b). After the forage harvest in June 2025, Foxtail Barley (a common weed in the area) was observed to have invaded the plots (Figure 4c).
Results
The baseline soil parameters for treatments are presented in Table 2. Nitrates (NO3) and soil organic carbon (SOC) generally decreased with soil depth, while sulphates (SO4) and electrical conductivity increased with soil depth. The soil electrical conductivity values were high, ranging from 10 to 14 dS/m, and fall under the strongly to very strongly saline salinity ratings (GoA, 2007).
Botanical Composition and Forage Yield
The percentage of seeded grasses in the various treatments at harvest 1 year after seeding is shown in Figure 2. On average, seeded forages accounted for about 25% of plots, while unseeded grasses (weeds) accounted for roughly 75%, with no significant differences between treatments. Across all treatments, the following grass species persisted most: CDC Salt King hybrid Wheatgrass (17.6%), AAC Renegade Crested Wheatgrass (13.8%), and Revenue Slender Wheatgrass (12.8%). The following grass species persisted least: AC Rocket Smooth Bromegrass (4.8%), Barolex Tall Fescue (4.3%) and Courtney Tall Fescue (3.1%). Alfalfa, which was part of the blend in three of the five treatments, did not persist despite having successfully established (Figure 4b).
Forage DM yield ranged from 3,300 to 4,300 lbs/ac (Figure 3), with no significant differences between treatments.
Figure 2: Percentage of grasses and weeds in treatments
Figure 3: Forage DM Yield of treatments
Figure 4a – Plots showing some alfalfa seedlings at establishment (summer 2024).
Figure 4b – Plots showing luxuriant forage growth just before forage harvest (June 2025).
Figure 4c – Plots showing invasion of foxtail barley after forage harvest (July 2025).
Forage quality
The forage quality of the treatments is shown in Table 3. The forage was of very high quality (most likely due to clipping during the early vegetative stage), with no significant differences between treatments. The nutritional composition ranged narrowly between 15.5% and 17.0% (CP); 66.0% and 66.5% (ADF); 0.21% and 0.24% (Ca); 6.5–7.5 ppm (Cu); and 140–225 ppm (Fe).
Conclusion and Future Plans
Establishing vegetation in a saline seep can be challenging, as evidenced by the results presented here. The Wheat grasses established relatively better than the other species (Bromegrass and Tall Fescue), but after the first production year, there was a complete absence of Alfalfa in the stands, and a noticeable decline in seeded grasses after harvest, with Foxtail Barley weed having invaded all the plots thereafter. These results confirm earlier assertions in (GoA, 2007) that Foxtail Barley is a salt-tolerant species, while Alfalfa seedlings are only slightly to moderately salt-tolerant. We will continue to monitor the plots for forage production and botanical composition in 2026 and 2027, and take final soil samples in 2027 to compare with the baseline data for any improvements in forage and soil parameters.
References
GoA (Government of Alberta). (2020). 2020 Agriculture – Statistics Factsheet. (Agdex 853) Alberta Agriculture and Food.
GoA (Government of Alberta). (2007). Perennial Forages for Saline Seeps. (Agdex 519-19) Alberta Agriculture and Food.
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