Sainfoin – Alfalfa Mixture Trial

Collaborators: Dr. Surya Acharya, Agriculture and Agri-Food Canada, Lethbridge

Trial Location: Fairview Research Farm NW-5-82-3-W6 on RR #35, MD of Fairview

Research Coordinator: Dr. Akim Omokanye

From: Peace Country Beef & Forage Association 2015 Annual Report

Sainfoin is a perennial forage legume that does not cause bloat and is immune to attack by the alfalfa weevil. Established sainfoin plants grow rapidly early in the season and appear to make good use of available moisture during this period. Sainfoin grows upright, making it easy to harvest as hay. It also has excellent leaf retention. Sainfoin is best suited to a rotational grazing system. It can be grazed mid-summer or stockpiled and grazed in the fall. However, old sainfoin cultivars do not persist in alfalfa stands for long and in new mixed stands do not regrow at the same rate as alfalfa after cutting or grazing. Recent studies conducted in Alberta and Saskatchewan by AAFC researchers have looked at the potential of including new sainfoin varieties in alfalfa pastures for grazing. They found that these new varieties are more competitive and have improved regrowth rates compared to some older varieties, and that including 20-30% sainfoin in an alfalfa pasture significantly lowers, and in certain cases eliminates, the risk of bloat. PCBFA seeded some experimental Sainfoin lines in mixtures with AC Grazeland alfalfa variety to evaluate their adaptation, growth, persistency, forage yield and quality in parts of Alberta. This will help us determine if these new sainfoin lines developed for their ability to survive with alfalfa can outperform the old cultivars in Western Canada.

Methods

The project was seeded in May 2013 at Fairview Research Farm (NW5-82-3W6) on RR #35. Soil tests prior to seeding showed a pH of 5.4 and 8.8% organic matter. Suggested seeding rate was: sainfoin 30 lb/ac, alfalfa 12 lb/ac. As these were seeded in the same row mixtures, we seeded at ½ rate; sainfoin at 15 lb/ac and alfalfa at 6 lb/ac. Seeding was 0.5-0.7” deep, and the seed was inoculated. Small plots measuring 1.4 m x 8.5 m were used. Fertility according to soil tests was 40 lb/acre of 11-52-0. Assure II and Basagran Forte were used to control volunteer oats and canola and other broad leaf weeds in 2013.

The forages were arranged in a randomized complete block design with four replications. Three experimental sainfoin lines designated LRC05-3900, LRC05-3901, LRC05-3902, and Nova (check) were seeded in the same row with AC Grazeland alfalfa. Cutting was supposed to be done twice, first cut when sainfoin is at 40-50 % bloom (alfalfa was at 20-30% bloom), and the second cut at 6 weeks after the first cut. This year, only one cut was possible because deer had selectively grazed down all sainfoin stands in the mixtures just before the second cut was to be taken. The regrowth was again grazed by deer.

Field measurements taken are dry matter yield (DM) and percent composition of sainfoin and alfalfa in the mixtures.

Results

Total Forage Dry Matter (Table 1)

The total DM of the first cut was statistically similar for all mixtures. The total DM for first cut varied from 3417 lb/acre for Nova sainfoin/alfalfa mixture to 4971 lb/acre for LRC05-3900 sainfoin/alfalfa mixture. 2015 was dry, but the spring moisture played a significant role in the forage DM obtained for first cut.

Proportion of Sainfoin and Alfalfa (Table 2)

The proportion of Sainfoin in the sainfoin/alfalfa mixtures for the first cut (the only cut) in 2015 was highest for LRC05-3902 Sainfoin (41.4%), followed by LRC05-3901 Sainfoin (37.5%), LRC05-3900 Sainfoin (26.4%) and then Nova sainfoin (18.1%). The proportion of AC Grazeland alfalfa in the sainfoin/alfalfa mixtures was consistently higher for Nova sainfoin/alfalfa mixture (81.9%). Other mixtures had 58.7 to 73.6% AC Grazeland alfalfa in the mixtures.

Summary - The results obtained so far here have shown that the old sainfoin variety used here known as Nova sainfoin may not be good competitor with alfalfa when seeded together in the same row mixture compared to new lines. As indicated earlier, studies in Alberta and Saskatchewan have shown that including 20-30% sainfoin in an alfalfa pasture significantly lowers, and in certain cases eliminates, the risk of bloat. So, in the present study here at the Fairview Research Farm, Nova sainfoin, which contained <20% in mixture with alfalfa may not have the potential to lower bloat when seeded with alfalfa in the same row mixture within a few year after seeding. One (LRC05-3902 Sainfoin) of the 3 experimental sainfoin lines used in this study has

recently been registered as Mountainview sainfoin.