Grazing Ewes on Cover Crops

Ewes Grazing Cover Crops

Well the rams have really been doing their stuff in the last 4 weeks with almost all of the ewes now hopefully pregnant.  In the first week over 600 ewes were mated, as indicated by the chalk dye that the rams leave of the rumps of the ewes during mating.  The colour is changed every week so we have an idea of which ewes are likely to be lambing and when. The gestation period is about 5 months so we're on for a mid April lambing, which next year will be outside for the majority of the flock for the first time.

At the moment all of the ewes are out grazing the cover crops on the arable fields.  The cover crops are a mixture of forage rye and vetch or black oats and vetch with a few extra goodies thrown in for good measure.  These extras include phacelia, buckwheat and berseem clover.

The hard spell of weather recently, although it didn't last very long, has certainly knocked the cover crops down but it hasn't killed them and we are getting some regrowth on the rye fields.  This will hopefully continue over the winter and into the spring to enable another grazing before the ewes lamb and the fields are planted with spring cropping. The field below is due to be planted with Soya Beans in late April so we should get a second grazing before then.

Cover Crop After Ewe Grazing

The ewes are doing a great job of eating the majority of the green material. But it's not just the cover crops, volunteer wheat and some black grass as well, whilst trampling some of the material into the soil to feed the microbes and worms. This is a great news as the field/soil surface looks well protected from the heavy winter rainfall that we must surely get at some point.  We'll have to watch it on the heavy land fields so that we don't get too much surface compaction if it gets too wet, but we are not there yet.  The soil has restructured itself  beautifully on the clay soil part of the farm enough to carry stock, but it has taken 3-5 years of no till to reach this point. There is still a long way to go until the spring so we'll have to see how things progress.

Crimper Conundrum

There is so much public awareness of the perceived issues with Glyphostate at the moment even though 3300 studies have shown it to be a very benign chemical when used correctly in the field.  With any potential restriction on its use being enforced on us I wanted to have a look at an alternative method of killing a cover crop before we plant our harvestable, or cash crop, into the field.  To me a cover crop can only enhance the soil and the wider environment.  It shields the soil from rain, reducing runoff and erosion; it feeds the soil biology with carbohydrates and encourages the development of below ground microbial populations; provides winter feed for our sheep; increases soil organic matter to hold more nutrients and water-its a no brainier for the farm and the wider environment.

Black Oat and Vetch Covercrop

Without glyphosate the termination, or killing, of these crops could prove to be very tricky in our maritime climate.  The cover crop can grow rather large and I don't want to have endless passes with toppers or cultivators to kill the cover crops.  Doing this is expensive, uses fossil fuel and releases CO2, cultivations mean even more CO2 released from the organic matter held in the soil, as it is exposed to oxygen, it means more tractors on the land, causing compaction where they drive which can lead to poorer water infiltration and therefore soil erosion.  So what's an alternative?

With a loan of a crimper roller from Cotswold Grass Seeds (thank you) we had a little play in a large cover crop of black oats, vetch, phacelia and berceem clover.

The idea of the crimper roller is to lay the plants down and squash the stems with metal blades in the hope that this bends or cuts the stems stopping nutrients getting up the stem into the top of the plants, end result being the killing of the cover crop, and any nests or wildlife that gets in the way-but we'll gloss over that for now!

Crimper Roller

We tried the crimper roller on the back of a tractor at first and drove in reverse to make the chevrons point in the right direction but ended up going in round in circles!  So we unhitched the weights from the front linkage of another tractor and set off across the field at 10kph, with the crimper on the front with a bit more success!  The roller weighed in at 620Kg for a 2m machine so about 310kg/m.

Crimped Covercrop 7 Days Post Crimping

I came back to the plot 7 days later to see if it had actually worked and I am sorry to say that it didn't. The oats seems to still be alive and the vetch, which I though would have been totally animated, were still just about hanging on.  The concern for me is we need to find something that works consistently every year and as every season if different.  We need to grow significant levels amounts of green matter and these need killing-somehow.

Maybe we used the wrong machine, maybe at the wrong time  for the plants growth stage,or at the wrong speed or it wasn't heavy enough?  Maybe we need to graze some of the covers down first to weaken then plants?  Maybe it just doesn't work in our climate where we don't always have a frost to follow up and finish off the wounded crop?  Who knows and more work needs to be done, but for now I am not impressed.

Magnificent Margins

Early summer is one of my favourite times on the farm when the hard work of the year, on so many levels, starts to pay off.  The ears of wheat and barley, the pods on the oilseed rape are starting to fill up and the countryside springs into life with a fantastic display of colours and different species. There is no doubt that we live in a sculpted and managed environment.  People are quick to forget this point and since the first settlers began turning their back on nomadic life, our landscape has become man made.

We must not loose sight of the fact that we need to create space for wildlife and mother nature in our very groomed landscape.  We need to create space for our insects to breed and in turn become food for birds.  The space can be populated by flowers adding to our enjoyment of our surroundings and we should take time out to appreciate these wonders.

Our field margins, that we cultivated last autumn are a wonderful mix of poppies, cornflowers and are alive with insects.  There are so many skylarks that tripping over them is almost a certainty!  They are nesting the wheat and barley crops in the purposely sprayed out skylark plots as well as the rough grassland periodically grazed by our sheep.  The diversity of the landscape is what makes it so special.  This must all be done in addition to providing safe, healthy and profitable crops that are wanted by our customers.  Growing wheat that ends up in Kellogg's Cereals as part of the origins group really enables a connection between farmers and customers, a connection we are proud to support.

We have also planted specific pollinator mixes around some of the oilseed rape field margins which are delivering huge benefits in terms of food supply for insects.  Mixtures of crimson clover, phacelia, daisy's and other annual flowers have been a great addition to the work we are doing on the farm to improve diversity of beneficial species and create a better habitat for us all to live and work in.

Cover Up or Laid Bare?

One of the key messages I have learnt from my Nuffield travels this year has been the need to look after  and feed the soil whenever possible.  This is fundamental to the farming system here in the UK.  If we look back 10,000 years the country was covered in trees and grasses; fields weren't created and there was no bare land.  It had something growing on it all of the time and this is what I feel we have to recreate now.  The soil is alive, or at least it should be.  It should be alive with bacteria, fungi and worms constantly re-cycling dead and decaying matter to release nutrients that we can then recycle.  With this in mind, the area of land going into spring cropping that doesn't not have a cover crop on it is down to the bare minimum 30Ha that we have as part of our Stewardship Agreement.

The picture below shows a field that has been split with two scenarios.  Half is in cover crops and half has been left as over winter stubble; although we had to do a light cultivation to get anything to green up.  Modern combines do not leave much grain behind.  The field will be direct drilled with spring barley next year and I can't wait to see what difference the cover crop will have made to the soil health, friability and structure.  Will it warm and dry faster with a crop on it?

The mix contains mustard, to produce organic matter, peas to fix a little nitrogen; oats, forage rye and volunteer wheat to mop up residual nitrogen, fodder radish to push tap roots into the soil and reduce compaction and turnips, just in case we run some sheep over the field.  I have a few observations so far that I would like to share.  The crop needs to be established as soon as the combine leaves the field to maximise the moisture left in the soil.  Any soil surface exposure to sunlight and no crop cover and vital moisture is rapidly lost.  This was a lesson learnt in Oklahoma where a second crop of sesame was being planted directly into wheat stubble in 45 degree heat!  Where the soil is moved we are getting a nice germination of weed seeds as well, so there is a nice flush of black grass and brome, all adds to reducing the seed bank in the top few inches of soil.  The field also walks well, it's hard to describe but it appears to have a cushioned effect, that can only be the organic matter that later will be returned to the soil.  Did you know that a 1% increase in organic matter in the top 6" of top soil means an additional 27,000 gallons/acre can be stored?  Well it's true, meaning that periods of dry weather will have less impact on our potential yields, especially on lighter, thinner soils.  I'm not expecting a fix in a year but over a rotation we should start to see a difference.  A more volatile climate is something that we should expect more often and we need to make plans to have a more resilient farming system. Prof Sir Brian Hoskins only mentioned last night at the Sainsbury's and Grantham Imperial College Lecture that temperatures could rise between 2-4 degrees by the end of the century, this will only cause more volatility in the climate, causing more weather extremes.  Last year for example 3,200 of the 5,000 weather stations in the United States recorded a record weather event  e.g. highest temperature, lowest rainfall, highest rainfall etc.

Another key benefit is the stabilisation of the soil.  All of the roots actively growing through the periods of heavy rainfall and the canopy above, shielding the soil surface will reduce water run-off and increase filtration rates.  Reducing run-off keeps soil particles in the field where they belong but also keeps phosphate fertiliser and any residual pesticides in the field rather than in the local stream.  I haven't even mentioned the amount of carbon that is being sucked out of the atmosphere and stored in the soil,  hopefully helping to turn around the recent losses of organic matter levels in the soil. Which ever way you look at it there are many positives.  But what are the negatives?  Well I guess there is the cost of the seed and establishment which when added together could be in the region of £80/Ha.  There is also the requirement for extra labour, and potentially machinery, at an already busy time of year when everyone is focused on the harvest. Do the positives out way the negatives?  Well it's early days but I would have to say that so far they do.  Are we creating a longer period for slugs to breed and feed?  Are we continuing the 'green bridge' and providing habitat for aphids transmitting BYDV (Barley Yellow Dwarf Virus) or too many brassica's potentially increasing the risk of club root?  Time will tell but as always with farming it's a long term game and there are many obstacles in the way before the results will be shown.  What I am certain of is that building soil carbon and reducing the level of tillage (cultivation) will, overtime increase the crop yields and reduce the variability of production and that can only be beneficial.

Planting Time is Here Again

The start of the new farming year has begun.  It's a time of optimism when the seeds from last years harvest are planted again to multiply up for harvest in about 11 months time.  We usually start planting, or drilling, up on the hill as the soil temperature there cools down faster in the autumn so the crops need to get established before this happens to optimise their yield potential.  Then we move down the hill to the heavy land, lias clay, to get those fields planted before the weather breaks.  We have to delay drilling in some fields to get a weed called black grass to germinate so that we can spray them off with glyphosate before we plant the crop.  This is needed as these weeds are resistant to many of the herbicides we can use in the crop.  The more we can remove, before planting, the better.  One of the things we have been trailing this year is a Cross Slot drill.  The idea of this drill, developed in New Zealand, is to cut a slot in the soil and plant the seed just under the surface on a little ledge and then fold back down the little flap of soil sealing the seed just under the surface. The drill is shown above planting directly into a standing crop of mustard.  That's another part of the story.

Our soil is a living organism and using this planting technique helps to keep the soil in the best health that we can get it.  Think of it as a natural environment.  Our landscape was once covered in trees.  Seeds fell from the mother tree and were not really cultivated in but rather mulched in with falling leaves.  That is what the drill is trying to mimic.  Low disturbance, slotting the seed under the surface.  This should in time reduce the amount of herbicides needed because the soil surface is not being disturbed so weed seeds will not germinate.  It also helps feed the worms in the soil by not mineralising soil carbon.  It also saves a lot of diesel in establishing the crop, all good for the environment, and the bank balance! In the picture above a worm hole can definitely be seen.  These worms take the organic matter from the surface down into the soil profile redistributing the nutrients to the rooting zone.  These worm holes have been known to go down 6'.  I've been watching out for these much more recently. The small piles of give away crop residue, hide the entrance to the underground world of these 'night crawlers'.   These channels provide fantastic drainage for surface water, stopping runoff keeping nutrients and pesticides in the field, we just need more of them and that will come with less disturbance and more time.  Did you know that ploughing kills 50% of the worms in that plough zone and every cultivation afterwards can potentially kill off a further 25%.

This is our current drill direct drilling into another cover crop mixture.  This mix was of mustard, phacelia and fodder radish.  The soil structure is fantastic with fabulous roots creating a fine tilth that should hold moisture and encourage a very good establishment of the winter wheat we have just planted.  The experiment continues!

All Covered Up?

Well this year is certainly making me think long and hard about the long term benefits of cover cropping when there is no other crop planted in the ground.  It is also making me think about leaving ground bare and I'm coming to the conclusion that we should be having crops growing all the time.  The soil microbes, fungi and bacteria all need to be fed to keep them healthy, this would seem logical wouldn't it?  Keeping the soil microbes healthy recycles nutrients within the system, keeps the soil structure maintained reduces soil erosion and increases water quality. It can also dry the land out faster and more evenly.  It also provides a great habitat for  our wildlife, I see an abundance of brown hare; we have skylarks serenading me as I walk the fields and lapwing swooping down to ward of visitors from their nests and young fledglings.

The field above is a mixture of Phacelia, Fodder Radish and a mixture of winter and spring beans.  The beans can, with the help of nitrogen fixing bacteria, turn atmospheric nitrogen into a form that the plants can use later in the season or it should be available for the next crop.

This is a fodder radish plant that has a tap root very similar to a parsnip by the looks of things.  It is penetrating the soil with the equivalent force of 400lb/square inch.  The picture above shows the root development 5 weeks since the crop was planted in a very cold and difficult spring (aren't they all these days).  I am hopeful that where the crop has established well there will be no need to subsoil this year.

As the cover crop plants die; the following crop, in this case winter wheat, their roots will be able to follow these roots down to the moisture in tracks already provided.  This means the wheat will use less energy to produce their roots enabling more efficient use of energy.  All in all there is no immediate financial return for doing this but the long term benefits will pay back with better yields and we'll have a farming system that is more resilient to the challenges of climate change that are all to obvious.  There will also be opportunities for moving livestock around the farm, returning more organic manure, I just have to work out how!