A COUPLE of months ago, I reported on all but two of the 2009 maize trial results, the omissions being due to an enormous amount of information which had to be condensed into a small but logical way of reporting – the two being a maize under plastic trial in North Devon and four sites for Pearce Seeds.

Maize Under Plastic
Jointly sponsored by J Picard of Burrington and Limagrain, the objective of this trial was to evaluate the performance of Limagrain material under plastic against the control variety Justina, which we believe to be the most widely grown variety in this particular sector of the market. Every variety was scored on the percentage of plants emerging through the plastic, maturity (dry matter percentage), dry matter yield, starch percentage and starch yield. A total of 52 varieties were tested, with 14 sown in two row plots and 38 sown in four row plots, with 15 varieties including the control being trialled both under plastic and in the open (conventional). The plastic used was 12 micron perforated plastic.

A soil analysis was taken prior to drilling with appropriate levels of N, P and K broadcast and harrowed in. Two tonnes of lime per acre were also applied. It should also be noted that it is impossible to apply any fertiliser ‘’down the spout’’ with the plastic applying drill.

Plant germination was greatly improved by the plastic with varieties averaging over 99 per cent compared to conventional drilling averaging 85 per cent – consequently overall sowing rates can be adjusted accordingly. The maximum number of plants that did not or could not emerge through the plastic was 2.5 per cent (two varieties), three varieties boasted every plant through, with an overall average of 0.75 per cent. The speed of emergence through the plastic was quite variable but did not have any direct relationship with either maturity or yields.

Plastic improved the maturity of every variety by an average of two weeks or four per cent DM. Initial observations suggest that plastic does not effect bulk but does influence dry matter and cob maturity which ultimately contributes toward a higher level of dry matter and starch yield – the improvement in dry matter percentage appearing to be gained during the first month after planting.

Ten days after drilling, plants under plastic were two inches tall whereas in the open sown trial, the seeds had a mere three quarters of an inch shoot underground – it being at least another two weeks before they reached two inches – this two week difference being carried through to harvest.

Virtually every variety under plastic performed within it’s original maturity classification, with one notable exception – Aurelia – a maturity class five under conventional circumstances but performed more akin to a maturity class eight under plastic.

All varieties, with the exception of Troubadour and Piazza achieved dry matter percentages in excess of the control, the differences ranging from 0.5 per cent to 8.0 per cent. All varieties, with the exception of Piazza achieved starch percentages in excess of the control with differences ranging between five per cent and 23 per cent.

Although many varieties could be described as being ‘’successful’’ in the trial, the one variety that really did stand out was Aurelia and it is this variety whose results I will quote against the control.

I must emphasise that these are one set of trials on one farm in one year, but the figures do tend to be supported by six years of trials work by the Department of Agriculture, Fisheries and Food in Ireland. A further J Picard/Limagrain “under plastic” sponsored trial will be carried out on a marginal site in North Devon this year.

As previously stated, the objective of this trial was to evaluate material from Limagrain’s breeding stable as to its suitability for growing under plastic – the results of which appear to be positive and although yields of over 6 tonnes per acre of dry matter were recorded, I am resisting the temptation of making a blanket recommendation for sowing maize under plastic. I will, however, go so far as to say that if you really are on a marginal site and that conventional sowings have been somewhat unsuccessful so far, maize under plastic has to be a serious consideration. You will need to cost out – accurately – what it will take to get the crop in the ground and then weigh up your budgeted dry matter and starch yields. Predicted harvest date will also be extremely important as you may wish to plant a following crop e.g. winter wheat or grass. Another factor that could be influenced by plastic is the drilling date – and depending on soil type (and that’s very important) you could, quite realistically, be drilling two or three weeks earlier than the “norm”. You then have to make the decision – is the extra yield of dry matter and starch worth it. Indeed, plastic may be the difference between growing maize or not at all.

Pearce Seeds Sites
Once again, I am indebted to Robert Baker, maize trials officer with Pearce Seeds who has kindly provided me with all the following information. I would add that during 2009, they undertook four trials – two on marginal sites with two on more favourable sites – the latter being independently sponsored with the request that the results are not published but are available from their Rosedown offices should anyone be particularly interested.

West Bourton (courtesy of Mr Alan Miller). A marginal site that had 18 varieties drilled on April 25 and harvested on October 7. The mean dry matter percentage was 26.85 with Artist and Destiny achieving 29.7 per cent and 30.3 per cent respectively. Mean dry matter yield was 4.38 tonnes per acre with Artist and Destiny yielding 4.22 tonnes and 4.95 tonnes per acre. Mean starch percentage was 25.62 per cent with Artist and Destiny recording 28.6 per cent and 24.8 per cent respectively.

Chard (courtesy of Mr Martin Burrough). Another marginal site that had 13 varieties drilled on April 30 and harvested on October 30. Mean dry matter percentage was 31.0 with Crescendo, Artist and Destiny achieving 33.6 per cent, 34.3 per cent and 34.8 per cent respectively. Mean dry matter yield was 4.49 tonnes per acre with Crescendo, Artist and Destiny yielding 4.35 tonnes, 4.58 tonnes and 4.25 tonnes per acre. Mean starch percentage was 26.2 with Crescendo, Artist and Destiny recording 32.1 per cent, 36.5 per cent and 36.3 per cent respectively.

And finally
With the visions of snow covered fields still firmly implanted in our minds, what better time to start planning for next winters feeding or, to be more precise, outdoor feeding. Like me, you have probably read recent press reports about farmers out wintering stock, successfully, on a number of crops and I am of the opinion that this is something that I could give a more in depth report on and, all being well, this is intended for April 1 publication.

As I understand it, this particular sector seems to be dominated by beef and sheep and not that many dairy cows – thus far. The ultimate objective is to reduce feeding costs and improve profits and the more obvious savings that would be achieved by ‘’in situ’’ grazings would much reduced costs on labour, machinery and winter housing costs. Grazing season would also be greatly extended. Realistically, your choice of crops would be restricted to probably just three – fodder beet, kale and Swedes and should you be considering fodder beet as the crop to grow, you will soon need to get some sort of action plan formed as April – the main drilling time for fodder beet – is not that far away – and is the main reason why I have chosen the February issue as the most appropriate time to (and please forgive the pun) ‘’sow the seeds’’.