Tag Archives: oat

Resilience to the 2018 drought

The 2018 summer of low rainfall was one of the driest on record. Cereal grain harvest dipped but did not fail, loss of production caused more by conditions in the previous winter than the summer drought. A further example of grain harvest’s resilience to untypical weather in the north-east Atlantic. 

The long summer of unusually low rainfall in 2018 parched much of the grassland and stunted many of the cereal crops. The wheat and barley appeared to suffer in many places. A record low for grain output looked set to happen. Yet the yield figures suggest a remarkable resilience to what turned out to be unusual weather for the region. 

First the rainfall …. How low was it? 

Daily rainfall records for East Scotland

The Met Office provides a valuable series of historical rainfall data. The analysis here uses the daily series for regions of the UK from 1931 [1]. The Met region ‘East Scotland’ is the one where most of the wheat, barley and oats are grown.  The period in 2018 from April to the end of August joins that of several other years in being unusually dry – 1955, 1976, 1981, 1984, 1995, and 2003 all had rainfall below 200 mm (Fig. 1). 

Fig. 1 Total rainfall between 1 April and 31 August for the East Scotland region in all years since 1931. The line just below 200 mm is the value in 2018. Years of low summer rainfall are arrowed. Data source: Alexander & Jones, 2001 [1].

There is little sign of any major trend in either low or high rainfall over the main summer period. Many of the other years after 2000 were much wetter than 2003 and 2018. The highest point in recent times was the very wet 2012, which had more rainfall than all other years except two. What distinguishes 2018 is the pattern of rainfall.

Many of the years having low summer rainfall had a fairly wet May, as evident in the steep rise in cumulative rainfall in 1976 and 2003 in Fig. 2. The same sort of thing happened in 1955 (not shown). This rainfall in May probably fills the soil enough to allow the crops to last through a dry June and July at which point most of the season’s growth has occurred.

Fig. 2 Cumulative summer rainfall, East Scotland from April for four dry years including 2018 (symbols). Data source: Alexander & Jones, 2001 [1].

2018 had a wetter April then most other dry years but then low rainfall until late July. Although 1984 had the lowest rainfall overall, 2018 had the lowest from late April through to mid-July, which is when the solar income is large and when the crops are bulking. Summer rainfall in 2018 would have been less than in 2003 if it had not been for that rain in late July and early August.

So did this low rainfall during crop bulking have an effect?

Yield figures for 2018

Each year the Scottish Government provide absolute records of crop-areas (i.e. all fields counted) and estimates of yield per unit area based on data from a range of sources. The final estimates are published in December [2].

The wet year of 2012 provides a comparator: most crops but particularly wheat, oats and oilseed rape produced a low yield per unit area that year because of waterlogged soil and low solar income [3]. Total cereal output was lower than in any other year of the past two decades. 

The records show 2018 yields were no worse. Wheat yield per unit area (t/ha) was down to near the 2012 value but most of the other crops showed little fall in yield (Fig. 3). When expressed as a percentage of the average of recent years, the simultaneous dip among crops in 2012 was not repeated in 2018 (Fig. 4). 

Fig. 3 Grain yield of wheat (red), oats (black) and oilseed rape (blue) over the last 20 years.

Was anything different about 2018. Total cereal output (the sum of wheat, barley and oats) was low, in fact just above the 2012 value, but this was due to reduced land areas sown with cereals, mainly winter barley which was sown in the autumn of 2017 before the summer drought of 2018. Sources in [2] state ‘Winter barley area dropped by a fifth due to poor weather conditions. This, along with a four per cent drop in yield resulted in production decreasing by 24 per cent.’ The greater effect therefore occurred before the winter and ‘was a result of the difficult weather conditions in late 2017.’

Fig. 4 Grain yields in Fig. 3 as a percentage of the average over the period, wheat (red), oats (black), oilseed rape (blue).

It appears therefore that yields per unit area – the best guide to the effect of weather on the summer bulking conditions – were not strongly affected by the 2018 drought.  

Caution is needed because the yield figures are an estimate, i.e. not measured for all crops. Some crops were not harvested for grain at all, where the weather ‘resulted in a number of farmers choosing to whole-crop due to the low yield and quality [2].’ (Whole-crop means to take all the crop for feed without separating the grain.) Some of the poorest yielding fields might have been removed from the estimate of yield therefore. 

Could grain yields collapse in this region?

Drought leads to zero crop yield in many countries. Even in parts of Australia, where standards of agronomy and resource-use are high, recent droughts have led to total failure of cereal crops that are not irrigated. 

So could crop failure occur here? In principle yes. But it would have to be a much drier year than any since the records began in 1931. Given there is no discernible trend towards low summer rainfall and that most years between 2003 and 2018 were wet, and two of those years – 2014 and 2016 – produced among  the highest mean yields ever in this region, there are certainly no indications that summer droughts will become a feature of the Atlantic maritime cropland.

Then again, you can’t trust the weather …. [4].

Sources, links

[1] Daily rainfall series from 1931: Alexander, L.V. and Jones, P.D. (2001) Updated precipitation series for the U.K. and discussion of recent extremes, Atmospheric Science Letters doi:10.1006/asle.2001.0025. Further information at the Met Office’s Hadley Centre web site: https://www.metoffice.gov.uk/hadobs/hadukp/

[2] Cereal and oilseed rape harvest: 2018 final estimates:  https://www.gov.scot/publications/cereal-oilseed-rape-harvest-2018-final-estimates/ Published 12 December 2018. See also https://blogs.gov.scot/statistics/2018/10/04/2018-scottish-cereal-harvest/ 

[3] Links to Living Field articles on high rainfall: The late autumn floods of 2012, Winter flood,  Winter flood … continued and Effects on corn yields of the 2016 winter flood.

[4] A fuller version of this article will appear on the curvedflatlands web site: link to be available later.

Author/contact: geoff.squire@hutton.ac.uk or geoff.squire@outlook.com

SoScotchBonnet

Indigenous crops; Scotch Bonnet; wool, woad and indigo; Tam o’Shanter, Burns supper; staple food of the north Atlantic seaboard; tatties, neeps, oat and barley; the grey cat!

In its undying search for the truly indigenous crop, the Living Field investigated the ‘Scotch Bonnet’, to find it was nothing local at all, but a hot little capsicum, now grown in the West Indies and other tropical places and used to give some spicy heat to food.

Why then is it called the Scotch Bonnet? It seems because it looks like one. Unlike many varieties of the chillies, this one bulges and sometimes flops when it leaves the stem: to some, with imagination, it resembles a Scotch Bonnet, on a head.

The Scotch Bonnet

Now the Living Field is well disposed to the headgear named Scotch Bonnet, originally made of local fibre, usually wool, and dyed blue with woad Isatis tinctoria, which was once grown as a crop in these islands, or with the deeper indigo Indigofera tinctoria, which is imported and replaced woad. Such skill and craft go into making this one little hat: you have to rear the sheep and shear them, then wash, spin and weave the fibre, grow and harvest the woad or indigo, extract the dyestuff, dye the cloth, then form it into a shape that would fit on a head – and it was all done before electricity.

But we see the Scotch Bonnet (headgear) is also called the Tam o’Shanter, and this is, it seems, because Tam in the poem by Burns wears a blue bonnet – it’s mentioned only once, but there it is – ‘Tam’s blue bonnet’.

Sheep being sheared of its wool (top right), wool dyed with woad (bottom right) and indigo, and photograph of scene from Gourdie's Tam O'Shanter showing Tam's blue bonnet in hand (Living Field / details of book below)
Sheep being sheared of its wool (top right), wool dyed with woad (bottom right) and indigo, and photograph of scene from Gourdie’s Tam O’Shanter showing Tam’s blue bonnet in hand (Living Field / details of book below)

Tam o’Shanter

Now these three words do not define what sort of bonnet it is, yet those who have depicted the bonnet in drawings and paintings of the epic give it the character and shape of a Scotch Bonnet, and those such as Alexander Goudie (1933-2004) who have painted in colour give it the colour blue – woad-blue or indigo-blue.

In Goudie’s fabulous paintings, the blue bonnet is there in almost every picture. It grows in significance. Even when chased by Cutty Sark and the other infernals, the blue bonnet stays on. Even when, with diminishing sark, she grabs Maggie’s (Tam’s mare’s) tail, pulls it and leaves just a stump of hair … the bonnet stays on. Considering the state of Tam, and the number and aggression of the infernals .. you wonder how the man and mare escaped? Was there something in these blue-bearing plants that somehow made Tam and his mare go faster or the infernals slower. Doesn’t matter, because if they had caught him, there would be no recitations of the poem and much less fun at Burns Night.

Burns Night

The poem Tam o’Shanter is very much associated with the festivities of the Burns Supper, and through the medium of the Supper, visitors can sample some of the great staple food and drink of the north Atlantic seaboard – oat, swede, potato and barley. Together, and with offal, including lungs, and other fleshly stuff from sheep, they make the traditional meal of haggis, neeps and tatties, the barley going not so much into the haggis as into the dram for those who partake (though, on the Night, the dram can sometimes … well … go into the haggis).

Haggis, neeps and tatties (top), whole swede and sliced swede (Living Field)

Would Burns have known the main crops that now form his Supper – he was a farmer for a few years? Sheep of course he would have known. Of the three main vegetable constituents, only oat has been here for a long time and that for thousands of years. He would have known oat. The neeps, usually swede rather than the (white) turnip, and tatties (potato) are relative newcomers, arriving perhaps a few decades before Burns was born. Burns probably knew about swede and potato but might not have grown them. Barley is older than oat here and he would have known barley and certainly known its products.

So while Burns (1759-1796) is now celebrated around the world, the world reciprocated before he was born by offering the vegetable constituents of his commemorative supper – oat and barley from west Asia, swede from (probably, though it’s not certain) east Europe or west Asia and potato from Central America. What a generous world!

Sources at the bottom of the page give links to his poems and song and to the Scots Dictionary. The image of haggis, neeps and tatties (above) was taken at a Burns ‘lunch’ at the Hutton staff restaurant.  For those who want to know more about the crops, below is something more on swede, potato, oat and barley.

The crops

Tatties

The tatties’ tale is well told elsewhere. Briefly, potato Solanum tuberosum arrived in Britain from the other side of the Atlantic in the late 1500s, but gained little interest other than a garden curiosity until …..

“To Thomas Prentice, a common day-labourer, who lived near Kilsyth, is the honour due of bringing this useful esculent into general notice in Scotland [so wrote Lawson and Son in 1836 only 40 years after Burns’ death … and read on … ] He procured, in 1728, some “sets” from Lancashire, and bestowed considerable care in their propagation; and as their value became known, they were eagerly sought after by his immediate neighbours. By continuing the cultivation he, in a few years, saved upwards of £200, with which he purchased a small annuity, on which he lived independently to an old age, dying at Edinburgh in the year 1792.”

So Thomas got his tattie tubers from Lancashire well before Burns was born and he died only a few years before Burns did. Burns was probably familiar with the potato, but only just. His parents’ generation probably did not know it and his grandparents’ would not have known it. Yet what an explosion of genetic resources there was after that, because little over a hundred years later there were 175 recognised types of potato known to Lawson and Son (1836, 1850) and today there are great collections of genetic resources such as the one at the Hutton Institute.

Neeps

In their list of 1852, Lawson and Son, seedsmen from Edinburgh, write “in modern times the turnip seems to have been re-introduced to this country from Flanders about two-hundred years ago” which is the 1650s or thereabouts, but they also state that the time of introduction and the degree of cultivation of the swede or Swedish turnip is less certain though probably later (let’s approximate to around 1700). By Burns’ time the turnip had become a commercial farm crop in some areas of Scotland. Today the turnip has the botanical name Brassica rapa and the swede Brassica napus.

Both types of turnip were used to feed horses and cattle, but also people. The swede, the same species as oilseed rape, has leaf that is less coarse and hairy than the turnip, bluey-green rather than bright green and generally a yellow-orange flesh rather than white, which colour remains when cooked and mashed. So the neeps that are eaten these days with haggis and tatties are mostly swedes. An excellent vegetable, rich, smooth and distinctive to the taste, one of the very finest of the cabbages.

The corn

Oat Avena sativa and barley Hordeum vulgare had been the staple cereals of the north atlantic seaboard for a very long time. Charred grain of barley has been found in the earliest farming settlements. Their relative popularity has risen and fallen but in Burns’ time, oat was by far the most common, and it is the meal ground from oat grains that binds the animal constituents of the haggis. Today it’s the other way round, barley is the commoner crop, though oat is the one still used in haggis. More on oat and barley can be found on this site at Garden/Cereals and in the series of articles on landraces, e.g. The bere line – rhymes with hairline.

The grey cat?

She says “Arrived, invited, for a SoSCOtchBOnnet photoshoot posing in nothing but a Scotch Bonnet – and what a bonnet! Fine wool, indigo-dyed, cost me the earth … credit card maxed out … but the editor says ‘no nudity on the Living Field web site’ and I had to keep my fur on … no fun in that. Name’s Meggie by the way, like Tam’s horse Maggie but with an ‘e’. I do photoshoots. Call me.”

The grey cat, enigmatic with natural dye strips (from top) hazel catkins, indigo, dock, rhubarb and (vertical) madder (Living Field)

Sources

Burns poetry. Best get a book of it – there are several – and read it by a fireside on a winter’s night or in a field of corn and poppies in midsummer.

Burns is accessible online, e.g. http://www.robertburns.org and http://www.bbc.co.uk/arts/robertburns/biography.shtml

Tam o’Shanter, a tale by Robert Burns, illustrated by Alexander Goudie. 2011. Berlinn, Edinburgh. More on the artist at http://www.alexandergoudie.org.uk at which – check under ‘paintings’ and ‘Tam o’Shanter’. 

A Scot’s dictionary is handy if you are not familiar, e.g. The Concise Scots Dictionary (The Scots language in one volume from the first records to the present day). Editor in Chief: Mairi Robinson, 1985. Aberdeen University Press. 

Online Scots http://www.scots-online.org and http://www.dsl.ac.uk.

Lawson and Son’s exhibitions and lists of 1836 and 1852 are described on this site at Bere in Lawsons’ Synopsis 1852.

What are landraces?

Before modern genetics and breeding, before the world’s great stores of genetic resources were built and before the purity of crop varieties could be certified using DNA tests, most crops were kept as landraces.

Seed of wheat, oat, barley, beans and all the other crops was usually highly variable, the individuals genetically different. When sown in a field in a year, those individuals that survived and yielded the most were those best fitted to the conditions. These fitter plants contributed more to the harvested seed than their less fit neighbours. Samples of seed were kept and then sown the next season. Again, plants that were most fitted survived and reproduced.

Gradually the nature of the seed changed by this repeated selection to track the local environment and growing conditions. This would have happened as the early cereals, legumes, fibres and oils were carried westwards and northwards from their Asian centres of origin to the margins of the Atlantic. Landraces evolved to cope with low soil fertility, a cold wet winter and the local pests, and would have split into recognisable types, known to belong to an area of land or method of farming.

But with little warning, a crop could be wiped out by extreme events, the farmers left with just a fragment, or none, of the seed they had nurtured for years, decades even. Maintaining a landrace was no easy matter. Many would have disappeared, others changed to adapt to new conditions.

Landraces are not a thing of the past. They are common in Africa and large parts of Asia today. Under-used  and under-researched crops such as bambara Vigna subterranea exist mostly as landraces, each typical of a region and maintained by seed saved from one year to the next.

Not so long ago in our Islands, crops were maintained as landraces, and the practice persists (see below), though most crops are now sown from bags of named varieties, each bought from a seed supplier, certified and uniform and generally high yielding.

More on this web site: Landrace 1 – bere

The Lawson list of 1852

The Synopsis of Vegetable Products of Scotland, prepared by the Edinburgh seedsmen Peter Lawson and Son in 1852 consists largely of named ‘types’ of cereals, legumes, fibres, fruit and all the other crops, but the types are not what would be considered true varieties today. Among the wheats, there were 142 types recorded, the barleys 42 and the oats 53 – each named with usually some note on their origin.

Some of the types on the list were recently imported, for instance, from the Baltic, from France, from the low countries, from England. But many of the notes suggest types were found and maintained by individual farmers in specific regions.

So there  is the Hopetoun wheat “the produce of  single ear of an unusual size … discovered in 1832, on Mr Reid’s farm of Drem, East Lothian … [which was passed through several farming hands and] … is now pretty widely distributed amongst growers ….”.

Or the St Madoes barley “discovered, in 1838, by the Rev. Mr. Noble of St Madoes, in a field of the Dunlop [another type of barley]; and is evidently of a very different kind … a recommendation in damp climates …” .

And then Dyock’s Early oat ” originally raised by a Mr Dyock, near Aberdeen, and has been grown in the vicinity of Brechin …. it is hardy, early, very prolific, and exceedingly well adapted for the higher corn lands”.

Most of those old cereal types are no longer with us, lost in the march  towards modern varietal uniformity, but what the Lawson list shows clearly is the vigour and intent of farmers working 100-200 years ago in their search for better crop seed, better for their region and purposes, better adapted to their conditions; and then the bulking and trialling of a new type over a few seasons, and the passing on of the good material to others.

Are there landraces still?

A few farmers save seed – it avoids buying it every year. (Possibly many more save it than would admit!) Yet not many landraces remain here – the traditional barley, bere, was recorded in the Lawson list as a four-row type, “chiefly grown in the Highlands of Scotland and in the lowlands on exposed inferior light soils”. Bere remains with us in a few places, notably Orkney.

There are also landraces of wheat and rye in certain collections and black oat must still persist mainly as a landrace.

The Living Field grows bere, and landraces of wheat, rye and black oat every year to compare them with modern varieties.  We save seed at the end of the year, keep it safe over the winter and sow it as a new crop next spring. All four types germinate well and grow fast.  They are different from their modern relatives, often taller, rangier, weedier.

Articles on the cereal landraces will appear on the Living Field web site in the coming weeks.

References

Lawson P and Son. 1982. Synopsis of the Vegetable Products of Scotland. Edinburgh: private press of Peter Lawson and Son.

Author/contact: geoff.squire@hutton.ac.uk