Tillage Update 5th August 2021
In this weeks crops update, tillage specialist Michael Hennessy gives an update on harvesting. Planting of oil seed rape can also commence and there is further information on this. Cover crops will also be highlighted with a useful video outlining the pros and cons.
Harvest Progress
Harvest is continuing, all be it slower than previous weeks. All of the winter barley is harvested with a good proportion of winter oilseed rape and winter oats are also harvested. Yields are good in winter barley with the average yields predicted to be close to 9.5t/ha. Winter oats are more variable with average yields predicted to be around 8.9 t/ha. The variability in oat yield is due to the effects of the cold spring combined with a growth regulators interaction. Reports of oilseed rape yields are thin on the ground so far but initial indications are that yields are at or above average (4.3t/ha). Good progress has been made in baling straw with most fields either baled or the straw fully cleared. This was helped by the excellent weather during the winter barley harvest but also the fact many farmers are chopping straw (as part of the DAFM SIM measure) which frees up time for baling straw.
Oilseed rape
Planting oilseed rape can commence shortly and an ideal target date for planting of August 15th. Planting in September is not recommended except for early sites and if a really growthy September and November can be guaranteed. Crops sown in August will germinate and establish quickly and get to the four true leaves quickly thereby helping to reduced risks from pests like slugs and flea beetles. Other advantages of a strong plant coming into the autumn are; the plant will utilise free nitrogen from the soils (which if not utilised will be largely lost by leaching), more competitive against weed competition, require less nitrogen in the spring (providing the crop has a good canopy in early spring), the crop will be more resilient to withstand pigeon grazing, and has a much stronger chance of achieving a consistently high yield across the field.
Planting into a good seedbed is essential to ensure the crop gets away quickly. The main varieties available are hybrids. Growers should look for a variety with excellent Light Leaf Spot resistance with other attributes such as pod shatter resistance and standing ability are all important. There are only three varieties on the DAFM recommended list this year but there are possibly another 10-12 varieties available. Carefully study variety information from other sources (non-Irish data) as many of the results are from trials in UK and further afield. This information can be a useful comparison but may not hold true when the variety is grown on your farm. A target plant population of 30-40 plants per meter squared in spring therefore plant for 45-50 seeds per meter squared. Check pack sizes (many are 1.5 million seed packs) and TGW to calculate the correct seeding rate.
Consider a pre-emerge herbicide as this can offer the best control of broad leaved weeds. However there is a broader range of post emergence options now so having a good knowledge of your fields weed history is the best guide to selecting the most appropriate option.
Ciaran Collins joined the Tillage Edge Podcast this week to chat through planting oilseed rape in 2021. Listen to podcast below:
Cover Crops
Cover crops or catch crops are useful in rotations to help keeping a living cover on the soil, trap free nitrogen which otherwise would be lost to water through leaching, help supress weeds and grow organic matter to return to the soil, which will improve soil organic matter and soil health. Richie Hackett, a researcher in Oak Park, has put together an excellent video, which outlined the pros and cons of planting cover crops, and goes into detail of results from Oak Park centring on cover crops planting dates.
It is very clear from Richie work that earlier sown crops (July 30) can produce up to 4.5 t/DM per hectare compared to late sown crops (Sept 8) which only produced 0.5 t/DM per hectare. When farmers are spending money on seed and establishment of these crops its important to get value for money from this spend and this lies in planting as early as possible. Click below to watch video: