Alternative Forage Crops for Winter 2022

Kevin O’Hara, Education Officer, Teagasc Ballinrobe

Many farmers will question an article about next year’s winter fodder supply while they still possibly have stock in sheds.  But, given the exceptional rise in input costs, now is the time to put a plan in place to have adequate animal feed on hand for the coming winter. In this article, I will look at alternative crops such as Kale, Forage rape or a hybrid of the two (e.g. Redstart). These crops are useful in that they can grow large quantities of Dry Matter (DM) in a relatively short period of time and are also a useful tool if housing is in short supply for the winter period.

Fodder crops can also be an excellent way of incorporating a break crop into a reseeding programme.  The field can be grazed during the winter months thus breaking down the soil allowing ideal conditions for early reseeding the following year if weather is favourable.

So where do you start? Firstly you must pick a suitable field.  It will need to be relatively free draining and have adequate shelter for stock over the winter. Ideally pick a field which could do with being reseeded in grass the following spring.

Secondly, decide what crop you are going to grow? This will depend on the time of year. Kale must be sown in the months of May or June while forage rapes or hybrids of the two can be sown any time from May until August. Kale is the highest yielder of the crops at roughly 8-10 tonnes DM/Ha whereas forage rape will typically yield between 3-5 tonne DM/Ha. So now is the time to decide what is needed.  One hectare of kale sown in May should feed the same number of stock as 2 hectares of a forage rape or hybrid crop sown in July.

After selecting the field you will need to spray off the area with a glyphosate product. This can be done a week before a crop of silage is too be harvested or onto pasture 10 days before planned sowing date. The ground can then be ploughed, disced and sown. There are multiple methods of sowing whether it be by precision drill or via a fertiliser spreader but the principles remain the same.  A fine firm seedbed is a must and generally rolling is required after sowing to get good soil seed contact. You will generally need 2-4kgs of seed per acre depending on sowing method and crop type. As the seed is very small it is generally mixed with fertiliser when being applied via a fertilizer spreader.

These crops have a high nutrient requirement and generally some of these nutrients are incorporated at sowing time (see table below for seeding and fertiliser rates). Farmyard manures and slurry are very useful when sowing such crops and are a cheap alternative to surging fertiliser prices at present. Soil pH is also critical as nutrient uptake will be reduced if soil pH is below 6.3. As a general rule of thumb 2 bags of gran lime per acre will be required, if ground is only sprayed off and disced, as the rotting grass creates an acidic environment which will affect the tiny seedlings. 

How to feed a forage crop?

Generally these crops are fed in situ with strip wires which are moved daily and the crop is rationed out to stock.  As these crops are very high in energy and protein (20%), a roughage source must be provided, generally in the form of hay, silage or straw. These bales are typically left in the field at sowing or shortly afterward and a round feeder is moved every few days over the course of the winter. This can be labour intensive for some farmers so many farms now zero-graze these crops into cattle or sheep that are housed for the winter months. As these crops are low in certain minerals and trace elements a mineral bolus must be administered to stock prior to feeding. The crop can be grazed at any time but generally it needs to be eaten by mid to late march as it can become harmful to livestock if it goes to seed which generally happens after the last spring frost. As with all out-wintering excessive poaching is not allowed under GEAC.  Cattle should have access to a grass lie back area and soiled water runoff should be minimised.  A general rule of thumb is if feeding on a field with a slope, start feeding from the top of the hill down as the crop itself will stop much of the soiled water runoff. For any further information on forage crops contact your local Teagasc office.