With so many spring planting options having been eroded by time, many are now defaulting to spring barley, with a definite interest in a range of fodder crops. But is spring-sown oilseed rape an option at this point?

Growers who have already lost options like beans for rotation purposes ahead of wheat, or even seed crops, might still prefer to have a broad-leaved crop in the rotation.

Now that we are in May, different questions must be asked and answered. Spring rape does bring a break crop benefit to a rotation and it is also a crop that might not yet be regarded as late. But if you are not a regular rape grower, you will also bring a legacy of volunteer plants for quite a few years into the future.

These are incidentals. How important is a non-cereal break crop to you? Maize and fodder beet are also break crops, but they are less likely to provide a safe planting option next autumn, if that is a priority. Spring rape will be later maturing than cereals, but it should provide a safe autumn planting window.

Low-input crop

Spring rape is generally regarded as a low-input crop, with the possibility of no herbicide use and even no desiccation cost. Good early growing conditions are critical. It should also have no requirement for fungicide, with little or no insecticide cost. So, on balance, it is nearly €200/ha cheaper to grow than spring barley (Table 1).

There may also be a possibility of shaving some cost off of the spring barley costings in Table 1, but I did not do that in this example. The costings shown in Table 1 are adjusted from the Teagasc costings in its crop Crop Costs and Returns booklet.

The costings used for spring barley are those used by Teagasc and small savings might be made on fertiliser (nitrogen) and seed costs, but many growers might also add a growth regulator cost on later-sown crops if we get an intensive burst of growth during stem extension. In these costings, spring feeding barley inputs will cost €504/ha, whereas spring rape is put at €321/ha.

Importance of rotation

Cost is only one element of crop economics, which must now be considered across the rotation because of the impact of crop interactions. The challenge to make spring rape profitable is the sowing date implication for yield and the current price indication.

While spring rape has had some really good performances in recent years, the fact that we are sowing in May makes anything over 3t/ha (1.2t/ac) unlikely. And with a dry price indication of €350/t currently, I cannot value the crop at any more than €310/t green.

These costs and values put the gross margin for a 3t/ha crop at €170/ha. While this is better than kick in the teeth, it is essential to be aware that the sentiment on spring barley appears to have changed considerably from the numbers in the Teagasc booklet.

Assuming that the costs are the same, there is now a strong feeling at merchant level that prices at harvest will be much stronger than previous years and this changes the sums considerably.

As an indicator price, Teagasc rightly used €140/t for green barley. We know that has been drifting up in line with market pressures and now a number of merchants are quietly talking about prices up to and above €175/t for green barley for harvest. This changes the situation considerably.

The other big change is straw. Given the inevitable scarcity, unless spring barley area increases considerably, straw price is now being spoken of in terms of €20/4x4 bale out of the field.

Indeed, I hear that a number of farmers have been prepared to pay half this cost up front to secure supply. Allowing for a baling cost of €3.50 / bale, the straw value per hectare could be as high as 25 bales @€16 or €400/ha.

But straw yield is likely to be much lower and to prevent the figures from being skewed too much (and the possibility of some losses), I have used a straw value of less than half this at €160/ha.

Price is driving margin

Taking both of these cost/income scenarios in Table 1, the spring barley is costing €180/ha more than the rape to produce (€940/ha v €760/ha), but the economic outturn is quite different due to the higher value included for barley grain and straw.

Perhaps the value of rape will increase also, but there appears to be market factors at play which may help to subdue rape value relative to grain.

The flip side could also happen. Perhaps barley will not rise to these suggested levels, staying in the €165 to €170/t range instead.

At 6.5t/ha of barley, the gross margin (GM) is an estimated €358/ha versus €170/ha from a 3t/ha crop of spring rape. If barley price is €165/t, the margin from the same 6.5t/ha crop would be €293/ha. So, either way, barley wins out at this yield level and it is turning out to be somewhat attractive on owned land, even with the lateness of the season.

Many will ask about the realistic yield potential of spring barley sown in May – some of you have never experienced it. Well, there is no easy answer, but my experiences from even later sowing vary from 1.5t/ac to 3t/ac (3.7 to 7.4t/ha).

Good even establishment, combined with BYDV and lodging prevention, are critical.

The important thing to remember is that May is not necessarily equivalent to poor yields, but they can happen.