Written by: Buthaina Al-Maqtari & Akim Omokanye,
Location: Bill Fevang's Farm - High Prairie
From: Peace Country Beef & Forage Association 2019 Annual Report
Intercropping refers to the growing of at least two crop species in close proximity at the same time, leading to enhanced interspecific interactions and crop diversity. Intercropping systems involving cereals with legumes, have been observed to provide several major advantages such as higher total forage yield, yield stability and improved forage quality. Peas are usually included in mixes to improve quality of the feed. In the Peace Country region of Alberta, barley and oat are the major cereal crops grown for forages, although some triticale is also harvested as forages. Triticale is a dual-purpose cereal crop and it therefore has the potential to provide economic benefits for both grain and forage based production systems.
Objective
To compare the intercrops of several fall rye, spring cereals (oat, barley and triticale), subterranean clover and forage peas to monocrops for forage quality evaluation for livestock production in High Prairie.
Methods
The study site was at Bill Fevang’s farm in High Prairie. The site had canola the year before and it was sprayed with a pre-seed burnoff before seeding in 2019.
Experimental Design: 21 intercropping treatments in Randomized Complete Block Design with 4 replications.
The treatments tested and their seeding rates are:
1. Stettler Wheat - seeded at 34.3 plants/ft2 (control)
2. Brevis Triticale - seeded at 34.3 plants/ft2 (control)
3. Oravena Oats - seeded at 27.8 plants/ft2 (control)
4. Cattlelac Barley - seeded at 27.8 plants/ft2 (control)
5. 40-10 Peas/Cattlelac Barley - seeded at 75% of 40-10 peas+ 50% of Cattlelac Barley
6. 40-10 Peas/Brevis Triticale - seeded at 75% of 40-10 peas+ 50% of Brevis Triticale
7. 40-10 Peas/Oravena Oats - seeded at 75% of 40-10 peas+ 50% of Oravena oats
8. Jasper Peas/Oravena Oats - seeded at 75% of Jasper pea + 50% of Oravena oats
9. Jasper Peas/Cattlelac Barley - seeded at 75% of Jasper pea + 50% of Cattlelac Barley
10. Jasper Peas/Brevis Triticale - seeded at 75% of Jasper pea + 50% of Brevis Triticale
11. CDC Horizon Peas/Brevis Triticale - seeded at 75% of CDC Horizon pea + 50% of Brevis Triticale
12. CDC Horizon Peas/Cattlelac Barley - seeded at 75% of CDC Horizon pea + 50% of Cattlelac Barley
13. CDC Horizon Peas/Oravena Oats - seeded at 75% of CDC Horizon pea + 50% of Oravena oats
14. Oravena Oats/Stettler Wheat - seeded at 75% each
15. Oravena Oats/Fall Rye - seeded at 75% each
16. Cattlelac Barley/Subterranean clover - seeded at 100% Cattlelac Barley/40% of Subterranean clover
17. Cattlelac Barley/Fall Rye - seeded at 75% each
18. Brevis Triticale/Subterranean clover - seeded at 100% Brevis triticale/40% of Subterranean clover
19. Brevis Triticale/Fall Rye - seeded at 75% each
20. Corn/Fall Rye - seeded at 75% each
21. Oravena Oats /Subterranean clover - seeded at 100% Oravena oats/40% of Subterranean clover
Seeding date was on June 7.
The seeds were sown using a Fabro plot drill equipped with disc-type openers on 9” row spacing. Six rows that were 8 m long were sown per plot. Seeding depth was 0.75”.
Fertility (actual lbs/acre): 60 lbs/acre of 11-52-0 was applied to all treatments.
In-crop herbicide application was with Basagran Forte for both monocrops and intercrops.
Harvesting for forage dry matter (DM) yield determination and quality analysis was done on August 28. Forage samples were sent to A & L Laboratory in Ontario for quality determination.
Results
Forage quality parameters measured here are shown in Table 1.
Forage crude protein (CP)
The forage CP for intercrops was significantly highest in 40-10 Peas/Cattlelac Barley intercrop with 16.99% CP, followed closely by Jasper peas/Oravena Oats intercrop with 16.61% CP and then Horizon Peas/Brevis Triticale intercrop with 16.34% CP. All intercrops with peas produced 12% or more CP, except for CDC Horizon Peas/Oravens Oats, which had 9.64% CP. Intercrops with Fall rye seemed to produce lower forage CP than other intercrops as well as cereal monocrops.
Overall, in terms of forage CP, all peas/cereal intercrops were particularly impressive. All peas/cereal intercrops had higher forage CP than other intercrops involving 2 cereals (cereal/cereal intercrops). Also, all peas/cereal intercrops had higher forage CP than all cereal monocrops.
Backgrounding and finishing calves require 12 - 14% CP. In this study, only all peas/cereal intercrops met the CP requirements of these calves.
Energy
Energy for beef cattle is referred to as total digestible nutrients (TDN), Net energy for maintenance (NEM), Net energy for gain (NEG) and Net Energy for Lactation (NEL).
Oravena oats/Fall rye intercrop produced a significantly higher TDN% than any other intercrop in this study (78.5%).
The beef cattle rule-of-thumb for TDN is 55-60-65. In other words, mature beef cows require 55% TDN in mid pregnancy, 60% in late pregnancy, and 65% after calving to maintain body condition score. The TDN% required for backgrounding and finishing calves is 65-70% TDN. Generally, in this study all intercrops and monocrops, excluding Jasper peas/ Oravena Oats and CDC Horizon peas/Brevis Triticale intercrop, met the required TDN% for beef cows in mid pregnancy and late pregnancy. Generally, the majority of the intercrops and monocrops in this study produced the required 65% TDN for Lactating cows and young calves.
Oravena Oats/Fall Rye intercrop, and 40-10 peas/Cattlelac Barley produced a significantly higher NEM and NEG levels than all other intercrops, except for Cattlelac Barley/Fall Rye intercrop and Horizon Peas/ Cattlelac Barley. All intercrops and mono-crops tested here had adequate NEM and NEG levels for both young and mature cows.
Detergent Fibers
Acid Detergent Fiber (ADF) and Neutral Detergent Fiber (NDF) levels in forage are critical as they affect animal productivity and digestion, and provide a good prediction of animal forage intake. The increase in ADF levels is correlated to a decrease in digestibility, and an increase in NDF concentration is an indication of a lower forage energy.
Among the intercrops and mono-crops tested in this study, Oravena/Fall Rye intercrop had the lowest ADF concentration of 28% followed by 40-10 peas/Cattlelac Barley intercrop with 29% ADF. Looking at the NDF concentrations, CDC Horizon Peas/Cattlelac Barley intercrop, followed by 40-10 Peas/Cattlelac Barley had the lowest NDF concentrations of 42% and 45%, respectively.
Generally, apart from Jasper Peas/Oravena Oats, Horizon Peas/Brevis Triticale and 40-10 Peas/Cattlelac Barley intercrops, no intercrops and cereal monocrops (controls) provided sufficient Ca, P, Mg, K, Na, S for young and mature beef cattle.
Conclusion
In most cases, intercrops tested in this study produced a better forage quality in terms of CP%, TDN%, digestibility and nutrients than cereal monocrops (controls). When comparing intercrops in this study, intercrops involving CDC Horizon Peas/Brevis Triticale, CDC Horizon Peas/Cattlelac Barley, Oravena Oats/ Fall Rye and Brevis Triticale/ Fall Rye exceeded the TDN% and CP% requirements for both young and mature beef cattle. In addition, they produced sufficient levels of Ca, P, Mg, K, Na, S for a dry gestating beef cow. For the cereal monocrops, Brevis Triticale had the most forage CP and Cattlelac Barley had the most forage TDN.