Wholecrop silage offers an alternative to corn silage that can be harvested and ensiled across a wide dry matter range, providing the farm with a degree of flexibility not seen with other ‘starchy’ forages.
Forage and Sowing
Depending on the local climatic conditions, wholecrops can be winter or spring sown, either as a pure stand of wheat, barley or oats, or in combination with other leguminous crops (peas, beans, vetch, etc.) to provide a mixed stand with both energy and protein (photo of barley : peas mix).
Great consideration should be given to the ratio of the different forages planted in order to ensure the desired final feed. (Discuss requirements with your nutritionist.) Birds can dramatically reduce the amount of pea/beans immediately after sowing and … should be implemented to reduce seed removal by birds.
Wholecrop can be harvested over a wide range of dry matters (DM) depending on how the forage is to be treated. Additional treatment (urea and alkalage) exist but are not discussed due to inherent issues.
Harvesting of a pure stand of wheat/barley/oats is generally made 2 – 5 weeks before dry harvesting, therefore allowing re-seeding or a catch crop to be planted. The harvesting window is wide with the forage being able to be harvested either through conventional mowing and collection, or with the use of a kemper header.
Yield and nutritional value are dependent on climate, sowing rate and general arable conditions, but it is possible to achieve high starch levels (25%) with a yield of circa 15T DM/Ha under optimal conditions.
Wholecrops can be stored either as bales or ensiled in a bunker/pile. The stem of the wholecrop contains significant amount of air when baled/ensiled which means that the forage generally produces low density silage or low density bales, and that the silage is prone to aerobic instability (heating) during feedout, or yeast/mold growth if the storage system is not adequately sealed. Because of the low density and the high amount of ensiled air it is not recommended to put wholecrop into a bagging system.
If a mixed stand has been planted (bi-crop) the timing of harvesting of the standing forage is dependent on the dominant crop. Harvest time should be optimal to the dominant forage.
Optimal DM for fermented wholecrop is in the range of 35 – 45%, at which point the forage should be cut to approximately 25mm in length. As the DM of the forage rises the chop length should drop to afford better compaction. Wholecrop generally takes the following appearances at increasing DM:
- 30 – 35% DM … crop is green, stem is green, ear is green and grain has some milk
- 35 – 40% DM … crop is green, stem is starting to turn yellow, ear is green but starting to turn yellow and the grain is like soft cheese when squeezed (no milk)
- 40 – 45% DM … crop is green/yellow, stem and ear are yellow and the grain is like semi-hard cheese when squeezed
- 45 – 50% DM … crop is green/yellow, stem and ear are yellow and the grain is like hard cheese when squeezed
Wholecrop forages can be difficult to ferment, and, because of the air entrapped in the stem and the ‘stemmy’ nature of the forage. It is recommended that ensiled wholecrop be treated either with Sil-All or Sil-All Fireguard. Sil-All Fireguard may be used to treat the top area of the bunker/pile or the shoulder areas of the bunker/pile with the bacteria and salts working in combination to preserve the forage.
If Sil-All Fireguard (fermented and salts) is being used as a ‘top treatment’ it is recommended that the bunker be given a ‘final compaction’ after application prior to sheeting.
Wholecrop harvested at 55% DM or higher can be treated with acid and then ensiled. Harvesting is approximately 3 weeks prior to dry harvesting using a self-propelled forager with crimper. Acid should be applied at the manufacturers rate based on the forage DM and then ensiled as per fermented wholecrop.
It is recommended that a minimum 6 layers of wrap be used when baling wholecrop forages due to the likelihood of the wholecrop stems piercing the plastic, and it is strongly recommended that the bales are not stacked. Bales should be wrapped, moved, and stored within 2 days of being produced.