Cross Slot And Cover Crops Farm Walk

Basking in the first real sunshine of the spring, and on what turned out to be the hottest day of the year so far; in conduction with Agrii we hosted a fan walk looking at direct drilling and the use of cover crops on the farm.  We had farmers from as far a field as Kent (Tom Sewell and Guy Eckley) and Lincolnshire (Jono Dixon) and Wiltshire (George Hosier) as well as many closer to home.  The interest shown and the discussions started really made for a very interesting and educational day. 

We talked about drilling techniques and could direct drilling have an effect on weed populations and what about slugs with more crop residue (not trash) on the crop surface?  Can we control these issues more effectively with better, longer crop rotations, direct drilling and with less reliance on pesticides?  We talked about subsoiling and should we be doing it or whether we could use cover crops, as demonstrated by Jono (below) to do the subsoiling for us?

The roots of the cover crops can easily go down to 1m over an autumn and winter if planted early enough; the ideal time is when the combine is still in the field, when moisture is usually available to get the crop off to the perfect start, or even spun into the crop pre-harvest.

We also talked about the blend, or the mix of the cover crops and what purpose they are being grown for.  Are they there to protect the soil surface, or to remove compaction or to increase organic matter or to provide a winter forage supply for the livestock?  We also talked about nitrogen fertiliser and should we be investing in fertiliser to maximise the benefits of the crop and the financial investment of the seed?  It really was a great morning of very thought provoking idea sharing.  We ended up in the Yew Tree pub for chips and sandwiches before everyone headed home.  Thanks to everyone who turned up and contributed, and to Agrii for supplying the bacon rolls and the lunch!

Core Sampling For Nitrogen

Well its that time of year again when we go and test the amount of nitrogen left in the soil after the winter.  The nitrogen is measured after the winter so that we can take account of any nitrate that has leached (washed) out from the soil.  The nitrogen left in the soil has come form a few places.  There might be some that we applied, left over that the plants were unable to absorb in the previous crop.  Some has come from the breakdown of the plant material by soil microbes in the autumn, before the temperatures got too cold and the stopped working, and some has come form mineralisation of the soil, during cultivations.  It is important to have an idea of what nitrogen is available for the crop because it will affect how much we are allowed to add artificially and how much the crop needs to produce an optimal yield.  Artificial nitrogen is very expensive, has a huge carbon footprint, is potentially damaging to the environment so we need to be absolutely sure what we apply is used by the crop.  

The probe on the quad bike, is a service offered by Soil Quest through Agrii (first time we have used it), also logs the sample location with a GPS point, so that we can come back year on year to assess the variability between years.  There is some discussion as to the accuracy of the sampling (to a point) but over time it will show a trend of how much nitrogen is available to the plant and at what depth.  The probe samples soil between 0-30cm and between 30-60 cm, then the driver has to sample by hand the 60-90cm depth (if you have enough soil!)  

The results are back now and they are showing a range of between 48Kg/Ha on the sandy soil up to 61Kg/Ha on some of the brash soil.  These two I can understand but then I also have a heavy clay soil with a reading of 50kg/ha which seems odd.  I guess though all of these values are low, due to the heavy rainfall we've had all winter, so we will have to apply a greater amount of purchased nitrogen fertiliser this season if we are to produce out optimum, and not maximum yield.  Imagine if we were in an organic system, there would be very little nitrogen left over from previous clover leys to feed this crop.

Agrii Agronomy Day

On the 1st May I had a really interesting agronomy meeting (day) with Agrii down near Marlborough.  It consisted of a morning session in a rather chilly grainstore and an afternoon session outside in the first bit of sunshine I had seen for nearly a month!.  I met up and had a good conversation with Stuart Alexander from Soilquest (part of Agrii ) all about using precision farming techniques to really target nutrient application.  The Soilquest system works in a slightly different way to that of SOYL who's technology we have been using since 2006 but ultimately using expensive nutrients targeted in the correct areas of the field has to worth while both from a financial and environmental aspect.

Stuart had some really great pictures demonstrating how soil changes with a field.  As farmers we have been joining fields together to get more efficiencies, to use bigger and bigger machinery.  Many of the old field divisions, such as hedges or walls, were put in place where different soil types naturally occurred and those different fields needed different applications and handling and here we are putting them all back into one area.  Now we can try and manage those smaller parcels of soil differently within the same field, which can only lead to better yields with targeted management.  However, and this is where precision farming can be a loose arrangement; if we have a fertiliser spreader or a sprayer at 24, 36 or even over 40m wide then that is currently as precise on these inputs as we can get.  When using narrower seed drills (ours is 6m) that I feel is the way to start the process off by trying to create a more even establishment of plants at the start of the year.

In addition to the Soilquest team Dr Peter Gladders was there talking about disease levels in this years Oilseed Rape crops, especially sclerotinia, which at the time were not very threatening, (cooler night-time temperatures stopping the sporilation). He also spoke about the long flowering period that we may have with  these lower temperatures that could expose the crop to risk for a longer period of time, if the weather warms up.  Therefore timings of fungicide are crucial this year as there is no 'kickback' control on sclerotinia.  Verticillium wilt was also mentioned where there is potential to build up the fungi in the soil, with close rotations of rape and certain varieties, (such as Excalibur) increasing it's occurrence from 6% of the UK's arable fields. I will be out spotting the disease later in the year, usually about symptoms start appearing as the crop is getting ready for dessication.

Finally I found listening to Phillip Marr very interesting, he spoke about the flowers being formed in the plant in mid winter (say dec on a conventionally timed crop).  at this point the crop turns from being vegetative to being reproductive and new main root development stops.  All that happens through the spring and summer is the root cells increase in size giving an appearance of growth, so root development shouldn't be hindered in the autumn with poor cultivations or poor fertility, everything is linked together and can therefore only be managed with Integrated Farm Management it's where autumn metconazole has a great role to play.