Spring crops will welcome forecast rain
Mark Plunkett, Teagasc Soil and Plant Nutrition Specialist, takes a closer look at soil moisture deficits and offers advice on fungicide treatments for spring barley.
Soil moisture deficits (SMDs) have continued to increase due to lack of rainfall over the majority of the country over the last 3 to 4 weeks.
Currently in the southeast, SMDs are at 70mm on well drained soils (figure 1), which will be impacting on plant growth and development. Forecast rainfall amounts over the coming days will range from 5mm to 15mm depending on location as shown below in figure 1. This rain will be very welcome to ease the moisture stress, increase soil nutrient supply and keep crops moving at this stage.
Figure 1. Soil moisture deficits on Wednesday 7th June and predicted rainfall for June 7-13th (Met Eireann)
Spring barley
In 2023, due to spring weather conditions, there has been quite a spread on sowing dates of up to three months. This has resulted in crops with a large variation in plant development - from tillering for later-sown crops to flowering stage for earlier-sown crops.
Crops sown in mid-April have moved quite rapidly through plant growth stages over the last week and many of these crops are coming up to the ideal timing for the second fungicide application (T2). Research from Oak Park over the last decade shows that the ideal timing for the second fungicide application is at GS 49 – 'Awns Peeping' (pictured above). Fungicide timing trials show a grain yield response of 0.3-0.4t/ha compared to the later timings of ear fully emerged at GS 59.
The dry weather has resulted in lower levels of disease in spring barley compared to other years. Assess your crops and tailor fungicide programmes based on crop yield potential and disease levels present over the coming week. With the current dry conditions, ensure good water volumes (200L/ha) when spraying and ideally spray in the cooler part of the day to reduce the risk of crop stress.
Many of the late-sown spring barley crops are showing a range of major and trace element deficiencies, which is very much associated with the dry soil conditions. A combination of underlining magnesium and manganese deficiency are present in many of these crops; treat with a suitable foliar product to help alleviate the deficiencies. The forecast rain, which is required, will help with soil nutrient supply of both major and minor nutrients.
Crops open day
Teagasc and The Irish Farmers Journal have teamed up for the major tillage event of the year – Crops and Cover Crop Cultivations, which will be held at Oak Park on Wednesday, June 21st. Find out more about this event here.