Forage Performance of Cereal Cover Crops in Maryland

Nicole Fiorellino, Extension Agronomist
University of Maryland, College Park

Dairy farmers are constantly looking for sources of forage to meet their feed needs. One source that many of our region’s dairy farmers utilize is the fall planting of cereal grains that are green-chop harvested the following spring. Among the cereal species used for this purpose are rye, triticale, barley, and wheat. Per the Maryland Cover Crop Program guidelines, cereal grains planted as a cover crop prior to November 5 and suppressed via green-chop in the spring are eligible for the grant payment for participation in the Cover Crop Program.  In addition, per the Nutrient Management Regulations, a fall application of dairy manure is allowed to a field planted to a cereal cover crop.

Planting a cereal cover crop that will be green chop harvested fits well into the crop rotation used by many dairy farmers. The scenario that many follow is to plant the cereal cover crop following harvest of corn silage. Prior to planting the cover crop, an application of manure is made to the field. The subsequent planting of the cover crop provides incorporation of the manure into the soil. The fall and spring growth of the cover crop is supplied nutrients from the manure. At the same time, the cover crop provides protection to the soil from loss of nutrients via leaching and/or erosion. The objective of this study was to evaluate select varieties of cereal species for cover crop performance and forage production and quality.

Cereal varieties (21) representing four species (rye, triticale, wheat, barley) were evaluated at Central Maryland Research and Education Center – Clarksville Facility. Three replications for each entry were planted using a randomized complete block experimental design.  Planting date was October 11, 2019. The 3’ X 18’ plots were planted with a small plot planter with 6-inch spacing between each of the 7 rows. The germination percentage for each entry was used to calculate the seeding rate needed to establish 1.5 million seedlings. Good stands were established in most plots by late fall.

Our goal each year is to time spring biomass harvest with when entries reach late boot to early heading stage of development. With the cool spring this year, plant growth and development slowed, with heading delayed until mid-May for most entries (Table 2) and harvest dates varying among the entries (listed in Table 1). Each harvest sample was collected by cutting the plants just above ground-level from three center rows of each plot from an area 2.5 feet in length and from two areas within the plot. The samples were placed into cloth bags and dried using a forced air dryer set at 60o C where they remained until sample water content was zero. Each sample was weighed and is reported as pounds of dry matter production per acre (Table 1). Each of the dried samples was ground through a 20-mesh screen using a large plant grinder and the ground biomass samples were sent to Cumberland Valley Analytical Laboratory for standard forage quality analysis.

Cover crop performance is measured by amount of biomass produced and the concentration of nitrogen (N) in the biomass. These two factors were used to estimate N uptake (Table 2). The cool weather this spring delayed harvest of this study, likely contributing to the higher biomass and N uptake observed this year compared to last year’s trials. There was no significant difference in nitrogen uptake among the varieties tested. A number of forage quality characteristics for these cereals was measured (Table 2). The descriptions of the various quality characteristic are described here and in the footnotes at the bottom of Table 2. Crude protein (CP) is the N content of the forage, with higher protein representing better feed quality. This value was used to calculate nitrogen uptake of each variety (Nitrogen content = % CP/6.25). Both rye varieties and the barley check variety had significantly greater CP than the overall mean, with a number of triticale varieties having significantly less CP content than the overall mean. One rye and the barley variety also had rumen degradable protein (RDP) content significantly greater than the overall mean.

Neutral and acid detergent fiber (NDF, ADF) are measures of feed value and represent the less digestible components of the plant, with NDF representing total fiber and ADF representing the least digestible plant components. Low NDF and ADF values representing increased digestibility; ideally NDF values should be <50% and ADF values should be <35%. Values of both traits were above the ideal this year, as the late harvest resulted in more mature plants. Despite this, four triticale varieties (TriCal EXP 20T02, BCT 15509, BCT 18001, bCT 19005) had significantly lower NDF and ADF values than the overall mean, representing a digestible triticale varieties. This same variety also had significantly higher total digestible nutrients (TDN), net energy for lactation (NEL), relative feed value (RFV), and non-fiber carbohydrates (NFC), indicating good performing varieties.

The characteristic that best captures the overall forage quality performance is Relative Feed Value (RFV). A RFV of 100 is defined as the forage value that full bloom alfalfa would have. In addition to the triticale varieties mentioned previously, one additional triticale variety (TriCal Gainer 154) and the barley and wheat check varieties had RFV values significantly greater than the overall mean.

Though, none of these green-chop cereal forages are considered to be adequate as a stand-alone feed for a dairy operation, they can supply a source of forage used in a total mixed ration at the time of year when feed supply may be running short. When this forage benefit is added to the environmental benefit that is gained, planting winter cereal cover crops on a dairy farm can be a win-win decision.

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Acknowledgements

This work could not be accomplished without the assistance and oversight of all field operations by Mr. Louis Thorne and Mr. Joseph Crank. We acknowledge the assistance of the undergraduate students who work with Dr. Jason Wight (Shana Burke and Deonna Cousins) for their assistance with seed packaging.

 

Table 1. Average harvest date for cereal species evaluated in Clarksville, MD in 2019-2020.

    Variety Species Average harvest date
TriCal Exp 19R01 Rye May 11
Rye VNS (check) Rye May 4
Mercer Brand Tri-Cow 814 Triticale May 4
TriCal Gainer 154 Triticale May 4
TriCal Flex 719 Triticale May 13
TriCal Surge Triticale May 11
TriCal Merlin Max Triticale May 13
TriCal Thor Triticale May 13
TriCal Exp 20T02 Triticale May 13
TriCal Exp 20T03 Triticale May 13
TriCal Exp 20T04 Triticale May 27
BCT 15509 Triticale May 11
BCT 15513 Triticale May 27
BCT 18001 Triticale May 13
BCT 18002 Triticale May 13
BCT 19003 Triticale May 27
BCT 19004 Triticale May 13
BCT 19005 Triticale May 13
BCT 19006 Triticale May 13
Nomini (check) Barley April 14
P25R25 (check) Wheat May 27

Table 2. Forage and cover crop performance of cereal species evaluated in Clarksville, MD during 2019-2020 growing season.

Variety Species Biomass Yield

lb DM/a

Head

Date

1Nitrogen

Uptake

lb N/a

2Crude

Protein %

3Soluble Protein

% DM

4RDP

% DM

5ADF

% DM

6NDF

% DM

7Ash

% DM

8Total

Digestible

Nutrients

% DM

9Net

Energy

Lactation

(Mcal/lb)

10RFV 11Non Fiber

Carb.

% DM

TriCal Exp 19R01 Rye 20655 April 17 395 11.9* 6.7* 9.3 41.8 64.0 7.4 56.5# 0.57# 82.0 15.2#
Rye VNS (check) Rye 20490 May 3 351 10.7* 4.4 7.6* 42.5 65.6 7.4 57.2 0.58 79.2# 14.4#
Rye Mean 20573 April 25 373 11.3* 5.6 8.4 42.2 64.8 7.4 56.9 0.58 80.6 14.8
Mercer Brand Tri-Cow 814 Triticale 23096 April 23 344 9.4 3.9 6.6 39.3 62.4 7.0 59.1 0.60 87.0 19.5
TriCal Gainer 154 Triticale 22925 May 4 260 9.5 3.9 6.7 37.4 59.5 6.6 60.3 0.61 96.5* 22.7
TriCal Flex 719 Triticale 24363 May 13 296 7.6# 2.8# 5.2# 42.7* 64.6 7.2 57.3 0.58 80.0# 19.2
TriCal Surge Triticale 22601 May 13 312 8.5 3.0 5.8 40.8 62.0 7.7 58.2 0.59 85.5 20.1
TriCal Merlin Max Triticale 22618 May 13 295 8.1 3.1# 5.6# 41.1 63.4 8.0 57.3 0.58 83.5 19.0
TriCal Thor Triticale 27172 May 14 357 8.2 3.6 5.9 44.7* 65.3 7.8 55.7# 0.56# 78.0# 17.4
TriCal Exp 20T02 Triticale 23820 May 12 290 7.6# 2.5# 5.1# 34.5# 54.5# 7.0 62.9* 0.64* 106.0* 29.0*
TriCal Exp 20T03 Triticale 24867 May 13 341 8.6 3.0# 5.8 41.6 61.5 8.5* 57.9 0.59 85.3 19.8
TriCal Exp 20T04 Triticale 28459* May 15 343 7.6# 4.0 5.8 48.7* 72.6* 7.4 52.7# 0.53# 65.3# 11.3#
BCT 15509 Triticale 22927 May 14 318 8.6 3.8 6.2 35.3# 56.9# 6.9 62.1* 0.63* 100.5* 25.7*
BCT 15513 Triticale 28316* May 16 358 7.8# 5.0* 6.3 42.6 64.7 6.4 57.1 0.58 80.5# 19.8
BCT 18001 Triticale 25363 May 11 347 8.6 3.4 6.0 37.1# 56.7# 7.7 61.4* 0.63* 98.3* 25.1*
BCT 18002 Triticale 25654 May 12 318 7.8# 3.1# 5.4# 41.6 63.2 6.5 58.4 0.60 84.0 21.1
BCT 19003 Triticale 28526* May 16 329 7.2# 3.8 5.5# 47.4* 70.2* 5.7# 64.2* 0.55# 69.0 15.9#
BCT 19004 Triticale 28740* May 13 366 7.9# 2.8# 5.4# 41.3 62.2 7.0 58.2 0.59 85.0 21.3
BCT 19005 Triticale 24173 May 13 332 8.6 3.0# 5.8 36.6# 57.7# 7.1 61.4* 0.63* 97.5* 24.7*
BCT 19006 Triticale 27915 May 12 330 8.5 3.1# 5.8 36.7# 58.6 7.2 60.7 0.62 95.5 23.9
Triticale Mean 25358 May 12 329 8.3 3.4 5.8 40.3 61.8 7.2 58.7 0.60 87.5 21.1
Nomini (check) Barley 15044# April 23 341 14.2* 6.6* 10.5* 34.4# 55.6 9.0* 61.7* 0.63* 104.2* 19.2
P25R25 (check) Wheat 25376 May 16 189 7.3# 3.7 5.5# 34. 4# 53.7 5.3# 62.7* 0.64* 107.7* 32.4*
Overall Mean 24269 May 10 329 8.9 3.8 6.4 39.9 61.5 7.2 58.8 0.60 88.5 20.8
LSD0.1 3816 2 days 0.9 0.6 0.7 2.7 3.4 0.8 2.1 0.02 7.5 3.4
*,# Indicates the entry was either significantly greater (*) or significantly (#)less than the overall mean for that feed characteristic.
1Nitrogen uptake (lb N/acre) for each entry was estimated by multiplying the lb DM/ac X % nitrogen contained in the DM. The percent nitrogen for each entry was calculated by dividing crude protein by the conversion factor 6.25 which is the average amount of nitrogen (%) contained in protein.
2Crude Protein %: represents total nitrogen content of the forage; higher protein is usually associated with better feed quality.
3Soluble Protein %: non-protein N and portion of true proteins that are readily degraded to ammonia in the rumen.
4RDP (Rumen Degradable Protein): portion of crude protein that microbes can either digest or degrade to ammonia and amino acids in the rumen.
5ADF (Acid Detergent Fiber): represents the least digestible fiber portion of forage; the lower the ADF value the greater the digestibility.
6NDF (Neutral Detergent Fiber): insoluble fraction of forage used to estimate the total fiber constituents of a feedstock.
7Ash: mineral elements of the forage.
8TDN (Total Digestible Nutrients): measure of the energy value of the forage.
9Net Energy Lactation: estimate of the energy in a feed used for maintenance plus lactation during milk production.
10RFV (Relative Feed Value): indicates how well an animal will eat and digest a forage if it is fed as the only source of energy.
11Non Fiber Carbohydrates: represents all forms of digestible carbohydrates (starch, sugar, pectin, and fermentation acids) in the forage.

Table 3. Brands and companies in the 2019-2020 Maryland cereal forage trials.

Brand Address
Eddie Mercer Agri-Services, Inc. 6900 Linganore Road

Frederick, Maryland 21701

www.eddiemerceragri-services.com

Seed-Link Inc. 208 St. David Street

Lindsay, Ontario (Canada) K9V-4Z4

www.seed-link.ca

TriCal Superior Forage 12167 Highway 70S

Vernon, Texas 76384

tricalforage.com

Management Tips to Harvest High Quality Winter Forage

Jeff Semler, Principal Agriculture Agent
University of Maryland Extension, Washington County

Article adapted with permission from information provided by Tom Kilcer, certified crop adviser in Kinderhook, N.Y.

In most of our region, the warm temperatures have kick started the winter forage. This crop can give you the earliest and the highest quality forage for your livestock. Now is the time to add nitrogen and sulfur, which can save you on protein supplements by allowing you to harvest high-protein forage.

Yield potential was set last fall, depending on planting date and available nitrogen. These two factors generate the number of fall tillers that help set the yield potential for the following spring.

While planting date is the most important factor, there is still potential for economical yields so long as the stand came through winter.

1. Provide sulfur for more protein. Sulfur has long been an overlooked plant nutrient. Prior to the clean air act, our sulfur came in our rain. Sulfur is critical for protein formation and should be included with any nitrogen application to winter forage. For example, adding extra nitrogen — 115 pounds — without sulfur only provided 12% crude protein. Adding a lesser amount of nitrogen with sulfur provided 17% crude protein. For a field that did not get manure last fall (a major on-farm sulfur source) an effective ratio is roughly 1 pound of sulfur for every 10 pounds of nitrogen. This is good for all cool-season grasses in addition to winter forage grains, such as triticale.Sulfur is also critical for corn and especially sorghum, which can produce much higher protein in the forage.

2. Increase N application. Research has shown that even if you immediately incorporated manure the previous fall before planting, an application of spring nitrogen is still needed.

In one study, spring fertilizer application didn’t increase the spring yield of triticale on manured ground but it did raise the crude protein from 9% to over 19%, which can potentially save money on purchased protein.

Many farms apply between 75 and 100 pounds of nitrogen an acre in spring. Even if you applied manure prior to planting in the fall, it is suggested increase this to 125 pounds an acre to boost forage protein and save on purchased protein. Remember, a 3-ton dry matter yield at flag leaf stage will remove 192 pounds of nitrogen at 20% crude protein. What is not used by the winter forage will still be used by the following crop.

One caution, don’t try this higher rate on rye. Rye has limited tillering and produces a tall but thinner stand. It is very prone to lodging when more than 50 pounds of nitrogen an acre are applied.

Triticale is only two-thirds the height of rye and is resistant to lodging. Several university trials have found that triticale yields 35% higher than rye because of the higher tiller density.

3. Add an antivolatilization agent. It is highly recommended to add an antivolatilization agent in the spring. This will inhibit the urease enzyme from splitting the urea into ammonia that could be lost. Trials have found that urea loss in fields treated with an antivolatilization agent were 63% less than in fields that were untreated. The antivolatilization compound increases the chance of full return on your fertilizer investment.

4. Know when to harvest. For those new to growing winter forage, it is ideal to harvest at the flag leaf stage (stage 9) for optimum quality. Stage 8 does not have higher quality than stage 9, and you can get a substantial yield drag from harvesting too soon.

If temperatures are warmer than normal, push to harvest the forage at the flag leaf stage. Conversely, if it is at stage 8 and there is a week of rain forecasted, get it cut so you have quality forage.