Trial Site: Fairview Research Farm
Research Coordinator: Dr. Akim Omokanye
From: Peace Country Beef & Forage Association 2017 Annual Report
Corn is good for extending the grazing season. Corn would normally meet the energy requirements of mature beef cattle, but occasionally the protein content of corn may fall short of what is needed by cows at the late-pregnancy stage. For producers wanting to use corn silage for backgrounding calves, the 12-14% protein required by these calves can hardly be met by a sole corn crop. To improve corn forage protein, we tested tillage radish, peas, faba bean, soybean, hairy vetch, crimson clover and a cocktail mixture as companion crops with corn.
Objective
To assess the effectiveness of a variety of crops for corn intercropping systems in improving corn forage quality for young and mature beef cattle.
Methods
Project Site: Fairview Research Farm (NW5-82-3W6) on RR #35, MD of Fairview.
Previous Crop: Oats for greenfeed in 2016 and 2015
Site soil information (0-6” depth): Soil tests done at Exova laboratory (Edmonton) prior to seeding showed pH = 5.6 and organic matter = 8.0%.
The field was cultivated (disked and harrowed) before seeding.
Experimental Design: Randomized complete block design in 3 replications.
Treatments: The following crops and cocktail mixture were seeded as companion crops with corn.
Tillage radish
Crimson clover
Hairy vetch
Soybean (variety TH 33003)
Peas (CDC Horizon peas)
Faba bean (variety Tabasco)
Cocktail mixture containing: - Barley 48 lbs - CDC Horizon peas 8 lbs - Hairy vetch 4 lbs - Crimson clover 1 lb - Winfred forage brassica 1 lb - GreenSpirit annual ryegrass 1 lb - Sunflower 1 lb
Monocrop corn (check)
Seeding date was June 1 for both corn and the companion crops; Plot size: 11.04 m2 (118.8 ft2 )
Seeding method: 6-row Fabro plot drill with 9” row spacing. Corn was seeded in rows 27 inches apart. The companion crops were seeded between 2 rows of corn. All companion crops were seeded at 50% of their recommended seeding rates. The cocktail mixture was seeded at 7 lbs/acre. Corn was seeded at 30,000 kernels per acre.
Fertility (actual lbs/acre): We applied half of the recommended rates for corn following soil tests- 50 lbs N /acre + 14 lbs P /acre + 15 lbs K /acre + 10 lbs S /acre.
Sprayings: Pre-emergent with Roundup Weathermax In-crop spraying was done with Basagran Forte on corn with crimson clover, soybeans, hairy vetch & peas.
Measurements: Corn plant height measurements and harvesting of the crops (corn & companion crops) were done on September 05. Forage yield and quality were determined.
Results and Interpretation
Corn Plant (Table 1)
The monocrop corn had the highest corn height value (189 cm) followed closely by the corn plant from the corn/faba bean intercrop (184 cm). Overall, the order of corn height in the intercrops only was: faba bean > crimson clover >hairy vetch > cocktail mixture > soybean > peas > tillage radish.
The slower growth of corn in both peas and tillage radish intercrops could be due to the early vigorous growth of peas and tillage radish following seeding, compared to the rate at which the corn was growing earlier in the spring. As a warm season crop, corn requires higher soil temperatures for germination in spring and it grows well under high temperatures.
Forage Dry Matter (DM) Yield (Table 1)
For the corn intercrops, the corn forage DM yield value was highest for corn/crimson clover intercrop (9627 lbs/acre), followed by corn/faba bean intercrop (8763 lbs/acre) and then corn/hairy vetch intercrop (7264 lbs/acre). Only the corn/crimson clover and corn/faba bean intercrops appeared to produce slightly higher forage DM yield than the corn monocrop. The corn/crimson clover and corn/faba bean intercrops had forage yield advantages of 134% and 122%, respectively, over the monocrop corn.
Looking at the forage DM yield of the individual companion crop, hairy vetch had the highest forage DM yield (5107 lbs/acre) as a companion crop with corn. The forage DM yield of the other companion crops did not vary much.
The combinations of corn & crimson clover, corn & hairy vetch and corn & faba bean produced higher total forage DM yield (11698 - 12944 lbs DM/acre) than the combinations of corn & other companion crops (9140-9749 lbs DM/acre). All corn intercrops produced far higher forage DM yield than the monocrop corn. The total forage DM yield of intercrops as % of monocrop corn in order from highest to lowest was: corn/crimson clover (180%) > corn/hairy vetch (172%) > corn/faba bean (163%) > corn/soybean (136%) > corn/tillage radish & corn cocktail mixture (132%) > peas (127%).
Forage Quality (Table 2)
Meeting the basic nutrient requirements of beef cows is a key component of meeting cow herd production and profitability goals for the beef cattle enterprise. Adequate nutrition is vital for adequate cow reproduction, cow and calf health, and growth of all classes of cattle. Nutrient requirements of cattle change throughout the year based upon stage of the production cycle, age, sex, breed, level of activity, pest load, and environment.
Forage Crude Protein (CP): The forage CP of the intercrops (corn + companion crops) was highest for the corn/hairy vetch intercrop (14.8% CP), followed closely by the corn/cocktail intercrop (14.2% CP). Generally, the forage CP for the intercrops and monocrop corn was >10% CP. Hairy vetch has an initial slow growth in this area, but growth quickens in later summer/early fall when it becomes very lush with excellent soil cover. The impressive growth of hairy vetch later in the season coupled with continual growth of corn before the killing frost was thought to be responsible for the higher forage CP (14.2-14.8% CP) of corn/hairy vetch and corn/cocktail mixture intercrops.
All intercrops tested had sufficient CP for mature beef cattle. For backgrounding and finishing calves, which require 12-14% CP, both corn/hairy vetch and corn/cocktail mixture appeared to be outstanding combinations for these categories of calves. On the other hand, monocrop corn and soybean/corn intercrop were only able to meet the 9% CP needed by a dry gestating beef cow.
Energy: Energy gives the ability to use the building blocks for growth and other productive purposes. The forage TDN of intercrops varied from about 63% TDN for corn/crimson clover and corn/peas intercrops to 67% TDN for both corn/hairy vetch and corn/soybean intercrops.
The beef cattle rule of thumb for TDN is 55-60-65. This rule says that for a mature beef cow to maintain her body condition score (BCS) through the winter, the ration must have a TDN energy reading of 55% in mid pregnancy, 60% in late pregnancy and 65% after calving. The TDN requirements of backgrounding and finishing calves is 65-70% TDN. Looking at Table 2 below, all intercrops and monocrop corn exceeded the TDN requirements of a dry gestating beef cow, but only corn/tillage radish, corn/hairy vetch and corn/soybean intercrops were able to meet the TDN requirements of lactating beef cows. The corn/tillage radish, corn/hairy vetch and corn/soybean intercrops were also within the 65-70% TDN needed by young calves.
Minerals: The forage macro and trace minerals measured here were higher for the following intercrops than other intercrops or corn monocrop:
Forage Ca: corn/peas and corn/cocktail mixture, each with 0.84% Ca
Forage P: corn/hairy vetch and corn/cocktail mixture, each with 0.18% P
Forage K: corn/hairy vetch (1.37% K)
Forage S: corn/tillage radish (0.40% S)
Forage Mg: corn/soybean (0.45% Mg)
Forage Na: corn/tillage radish (0.37% Na)
Forage Cu: corn/hairy vetch (6.18 ppm Cu)
Forage Zn: corn/hairy vetch (48.3 ppm Zn)
Forage Fe: corn/hairy vetch (216 ppm Fe)
Forage Mn: corn/hairy vetch (45 ppm Mn)
Generally, corn/hairy vetch intercrops seemed to fare better than other intercrops and monocrop corn for most of the minerals measured here. Surprisingly, monocrop corn had higher levels of some minerals than some of the intercrops.
Except for forage P and Cu, of the 7 intercrops and monocrop corn tested here, only corn/crimson clover and corn/cocktail mixture intercrops were able to meet most of the mineral requirements of young and mature beef cattle.
Conclusion
The corn/crimson clover and corn/faba bean intercrops had forage yield advantages of 134% and 122% respectively, over monocrop corn. The combinations of corn & crimson clover, corn & hairy vetch and corn & faba bean produced higher total forage DM yield (11698 - 12944 lbs DM/acre) than the combinations of corn & other companion crops (9140-9749 lbs DM/acre). All intercrops tested had sufficient CP for mature beef cattle. For backgrounding and finishing calves, which require 12-14% CP, both corn/hairy vetch and corn/cocktail mixture appeared to be outstanding combinations for these categories of calves. On the other hand, corn monocrop and soybean/corn intercrop were only able to meet the 9% CP needed by a dry gestating beef cow. All intercrops and monocrop corn exceeded the TDN requirements of a dry gestating beef cow, but only corn/tillage radish, corn/hairy vetch and corn/soybean intercrops were able to meet the TDN requirements of lactating beef cows as well as those of growing and finishing calves that require 65-70% TDN.