This week we answer following key questions: when is the optimum time to apply topdressing fertiliser to canola crops? Should we be rolling seedbeds to improve Fall Armyworm control? And a reminder of herbicide pro’s and con’s for maize crops…
Initially we set out to look at the optimum Nitrogen and Sulphur dose rates for canola crops; lots of work has been done in other countries but I have always felt that not only do our crops grow extremely quickly which can influence the efficiency with which Nitrogen is taken up by the plant, and behaviour of Sulphur in some soils can be difficult to predict and has an important interaction with Nitrogen.
We have collected valuable information on fertiliser responses on soils in both Nakuru and Timau from 9 different combinations of Nitrogen and Sulphur, but we also applied one of the applications several weeks later to look at the effect of timing.
As I have pointed out before, the European approach is to apply early in the crops life with the bulk of fertiliser applied by the 3 leaf stage. Here we applied the treatments at 4-5 leaves, except the late comparison which was applied at mid stem extension.
It is important to understand the practical implications of this research;
We can confidently apply topdressing (Urea especially) late on for optimum yields.
With a late planted crop or when the rains have finished early, we might still want to apply early so that we have fertiliser in the crop – the penalty for getting this wrong is far greater than the penalty for applying the fertiliser too early!
For large scale farmers during busy workload periods, we can confidently spread applications of fertiliser from rosette stage to green bud stage without concern.
Read the spreader manufacturers handbook when spreading in tall crops to ensure the spread pattern is correct. Some smaller Kuhn spreaders require the toplink to be shortened to throw the fertiliser above the crop, older Amazone spreaders (below) have vane-tips that need to be pointed upwards.
Maize Herbicide Options – Some General Pointers
A reminder of the strengths and weaknesses of the different herbicides and how they fit into your own weed spectrum. Other products are available, and remember to always consult a professional agronomist before using any of the products below. Applied incorrectly or to inbreed male line of seed crops, some chemicals can cause serious crop damage.
Improved seed to soil contact means more even and quicker germination
Seals in moisture and firms the ground which can draw up moisture from depth by capillary action.
Allows higher planting speeds and less coulter bounce
A level seedbed is kinder on the sprayer during the growing season – important when lots of passes for Fall Armyworm are required. Less boom bounce equals better, more even application and control which for me is the most important aspect of good spraying.
Finally, a big thank you to the Agventure Center of Excellence for Crop Rotation and their assistance with our trials:
Farming for the future requires a change of approach. Monoculture, soil degradation and climate change and soil degradation are threats to the future of how we feed the planet.
Agventure Ltd set up the Center of Excellence for Crop Rotation to help farmers diversify cropping systems and introduce techniques which have a long-term outlook to improve soil health.
The Center of Excellence for Crop Rotation works extensively in partnership with Crop Nutrition Laboratory Services Ltd. (CropNuts), for trials and research.
Till next time,
David Jones is the Broad Acre Specialist at Crop Nutrition Laboratory Services Ltd. (CROPNUTS). David has a keen interest in soils and no till farming systems where he has undertaken work looking into weed levels and changes in soil structure, and has extensive experience in field trials and in the development of precision farming techniques. In his spare time he enjoys playing rugby.
http://cropnuts.com/wp-content/uploads/2018/04/TA1.jpg560741Cropnutshttp://cropnuts.com/wp-content/uploads/2017/07/logo497x156-2.pngCropnuts2018-04-03 15:08:442018-04-04 10:24:42Setting Up For Top Yields In 2018 (Part 3): Top Dressing