Arable Crop Report May 2014

Transcription

1 Arable Crop Report May 2014 Prepared for: Prepared by: AHDB HGCA and ADAS UK Ltd ADAS Boxworth Cambridge Date: 29 May

2 Summary Overview: May brought mixed weather with some settled spells interspersed with heavy rain, and more persistent and widespread rain at the end of the month. Air temperatures were around normal. Crops remain 7-10 days ahead of normal with typical wheat crops approaching ear emergence and oilseed rape at the end of pod set. Most crops are in good condition, but disease pressure is high in winter wheat with septoria and yellow rust the main problems, which are requiring robust rates of fungicide and timely applications. Black-grass is very visible, with an estimate of 30% of combinable crops having some black-grass at the end of May, some of which will have a yield impact. Most spring crops were drilled by end of April with the most forward March-drilled spring barley at GS31/32. Pest levels tend to be low, although aphids were becoming active towards the end of the month. Lodging remains a risk, although most high risk crops were treated with additional plant growth regulators. Wheat: The majority of wheat crops are at boots swollen (GS 47) to ear emergence (GS 55). The majority of crops are in good condition with high plant counts and good growth. However, there are visible patches of black-grass in many fields with an estimated 20% of the wheat area at risk of some yield impact from the weed. There is also high disease pressure from septoria and yellow rust. Most fungicides have been applied as planned, but where timings slipped or insufficiently robust rates were used, there are both septoria and yellow rust symptoms on upper leaves of susceptible varieties. T2 fungicides were applied during May, with the most forward crops due to receive T3 fungicides at the end of the month, weather permitting. Winter barley: Crop development progressed unchecked through May, with the majority of crops having completed ear emergence (GS 59) and starting to flower (GS 65). Black-grass is less of a problem in winter barley than in wheat, however, there are still a proportion of crops with high black-grass levels. Disease pressure is high particularly from rhynchosporium, but net blotch and ramularia are also present in some crops, although these have been controlled by standard fungicide programmes. Spring barley: The bulk of spring barley was drilled by the end of April, with just a small proportion drilled in May, often as a crop replacement for an unviable crop or after grass. The majority of crops established well and have grown rapidly in the mild and damp May. Some later drilled crops in the dry soils of the East struggled to get established until the rain in May. By the end of May typical crops were at first node detectable (GS 31). Flushes of broad-leaved weeds appeared during May, but these were effectively controlled with herbicide applications. Rhynchosporium is present in susceptible varieties. T1 fungicide applications were applied as crops reached one to two nodes (GS 31-32). Oats: The majority of winter crops had boots swollen (GS 45) at the end of May, whilst spring crops were at 1-2 nodes (GS 31-32). Herbicides have tended to give good levels of weed control. There were occasional crops with mildew or spots of crown rust, but these were largely controlled by standard fungicide applications. Winter oilseed rape: The majority of crops were nearing completion of pod development by the end of May, which is more advanced than most recent years. Black-grass control was good where autumn/winter herbicides were applied, but up to 30% of fields still have some present at the end of May, along with low levels of mayweed and thistles. Pest numbers remained low through May, with few crops requiring insecticide treatment. Sclerotinia levels were low at the end of May, but most crops were treated with fungicides as standard. i

3 Weather The weather in May was quite mixed, with periods of warm dry weather interspersed with periods of more unsettled, wetter weather. The month started with relatively settled conditions, with rainfall averaging 12mm in the first week (close to normal), with parts of the Eastern region and East Midlands even drier (Figure 1). Conditions became more unsettled in the week up to 13 May, with average rainfall of 29mm, ranging from 16mm in the South West to 40mm in the North West. Air temperatures were around normal for the time of year in the first two weeks of May, but rose during the 3 rd week of May, with temperatures climbing to an average of 14 C, which is 3 degrees warmer than normal for the time of year. Day temperatures reached the 20 s during this period and there was very little rain until the bank holiday weekend. Over the bank holiday (24-26 May) there was significant rain in the south and further bands of heavy rain moving in across the eastern side of the country during the week up to the end of May. The average rainfall for the week up to Tuesday 27 th, was 45mm and temperatures dropped back closer to normal at 12 C. Figure 1 Average rainfall and temperature from September 2013 to May 2014 Across England and Wales the average monthly rainfall for May was 88mm, which is 188% of normal. The wettest region was the East Midlands with 100mm of rain, and the driest region was the South West with 73mm of rain. Soil moisture deficits have remained within reasonable levels during May given the regular rainfall. Deficits were starting to increase in the drier eastern regions with SMDs on medium soils reaching 54mm before the recent rainfall. By the end of the month Yorkshire, the West Midlands, South East and Wales were near to field capacity and even the Eastern region was down to just a 30mm deficit. 2

4 Region Table 1 Comparison of SMD at the end of May 2009 to 2014 End May 2009 End May 2010 End May 2011 End May 2012 End May 2013 End May 2014 Average ( ) (mm) (mm) (mm) (mm) (mm) (mm) (mm) North East North West Yorks and Humber East Midlands West Midlands Eastern South East South West Wales Weather Effects Dry soils in the east In the eastern counties soils continued to dry out during May given higher crop demands and sporadic and relatively low rainfall in the early part of the month. This resulted in cracking of clay soils, and uneven emergence of late drilled spring cereals, peas, linseed and sugar beet. Heavy rainfall at the end of the month has reduced the problems, with deficits around normal. Spraying progress Dry periods in the first half of the month allowed most farmers to catch up on any spray operations, especially T2 flag leaf fungicide applications. Continued crop development Relatively mild temperatures and plentiful rainfall have allowed crop growth to be maintained with no checks to development. High disease pressure Disease pressure, especially in wheat, remains high as a result of favourable weather conditions for both rust and septoria development. 3

5 Black-grass an increasing challenge Black-grass is a serious issue for many farmers with winter combinable crop rotations on medium and heavy land, especially in the south and east of England. Black-grass is very competitive and has high seed return. Black-grass resistance to herbicides is an increasing problem due to heavy reliance on chemistry alone and reduced range of approved actives. In recent years there has been a move to more cultural control measures including appropriate cultivations, delaying sowing, using stale seedbeds and spring cropping, but herbicides are still an essential component of control. Black-grass control in 2013/14 was quite variable. Good autumn planning conditions allowed pre- and peri-emergence herbicides to be applied, and a higher than normal proportion of post-emergence Atlantis (mesosulfron-methyl + iodosulfuron- methyl) to be applied in the autumn. This is a more effective timing than in the spring, when black-grass plants can be too large for good control. However, despite broadly favourable conditions for control there are problem fields that are now visible as black-grass plants come into ear above the crop. An assessment of black-grass presence in crops at the end of May 2014 by the regional reporters shows estimates of the crop area affected at different levels of slight, moderate, severe and complete, for each of the main combinable crops. About 49% of wheat crops are estimated contain at least some black-grass, with about 20% of wheat crops expected to suffer some yield loss as a result. It is estimated that up to 1% of the crop area (often in patches of fields) is likely to be destroyed to prevent seed return. Black-grass tends to be less of a problem in barley crops, due to more being grown on lighter soils, with an estimated 26% of fields containing black-grass at the end of May and about 10% likely to have some yield impact. There is an increasing area of spring barley being grown on black-grass land to try and aid control and this is apparent in the assessment with 17% of fields affected to some degree but only 4% likely to have a yield impact. In oilseed rape about 37% of the area has black-grass present at the end of May with 11% likely to have some yield impact. Crop development Wheat Growth stages September mid-october drilled crops are very forward with the most advanced early varieties at ears fully emerged (GS 59) or starting anthesis (GS 62-3% of crop area), and the majority at boot swollen (GS 47-60% of crop area). November and December drilled crops are further behind with typical crops at flag leaf fully emerged (GS 39-29% crop area). Crop development is well ahead of average (Figure) and significantly ahead of development of crops in It is estimated that crop development is 7-10 days ahead of a normal year. 4

6 Figure 2 Comparison of wheat growth stages at the end of May, Weeds Overall the level of weed control this season has been good, excluding some problems with resistant black-grass (see black-grass an increasing challenge above). The general consensus amongst agronomists is that the highest levels of black-grass are present in the earliest drilled fields, especially where those followed poor rape crops the previous year. Later drilled crops have better control, with cultivations having helped reduce the early flushes. At this stage in the season there are limited options for managing black-grass. Farmers either have to accept the competition and hope yields are not significantly affected and worth harvesting, or take the decision to destroy the crop to reduce seed returns. Wild oats, tame oats, rye-grass, sterile brome and annual meadow grass have largely been controlled by planned herbicide applications. Broad-leaved weed control was good where pre-and post-emergence herbicides were used in the autumn. Follow up spring applications have also provided good levels of control. Late emerging cleavers remain a problem in a small proportion of more open crops. In areas where potatoes are included in the rotation volunteer potatoes are more common than usual, with a mild winter failing to kill off many tubers. This has resulted in more emergence than normal during May, requiring additional or higher rates of herbicides for their control. Pests Aphids are present in many crops, albeit below threshold levels. Concerns over autumn aphids and BYDV have not been realised, with few BYDV symptoms present in crops by the end of May. Wet conditions towards the end of May allowed slug populations to become more active once again, with a number of reports of slugs stripping leaves. This is not a significant problem at this stage of development, providing they don t damage the flag leaf. Despite this there were a minority of growers who felt the need to treat crops with slug pellets. 5

7 The most forward crops were reaching the vulnerable stages for orange wheat blossom midge at the end of May. However, monitoring data indicates that midge numbers are at their lowest levels in 10 years. Disease High disease pressure has been one of the main challenges facing farmers this season. In rust susceptible crops up to four fungicide applications have already been used (T0, T1, T1.5 and most recently T2), with crops needing treatments every days to maintain control. In crops with high yellow rust pressure, where fungicide timings have been compromised, there are symptoms appearing on upper leaves. Robust ear wash applications (T3) and possibly post ear wash will be required to keep these crops healthy through to harvest. In trial plots, untreated susceptible crops are already dead as a result of yellow rust infection. Septoria remains a threat in the majority of wheat crops. Its spread was reduced during the period of dry weather in April, but showers in May have started the spread of infection into the upper canopy. In the worst affected crops, many of the lower leaves are showing severe symptoms, although fungicide applications have protected upper leaves. The cleanest crops are those sown in late September through to early October, with a resistant variety and treated with at least three well timed fungicide applications. Mildew is not common, only present in occasional thick early drilled crops. Some has required targeting with a specific mildewicide at T2, but only in a minority of crops. Where fungicide applications were well timed, and robust application rates used the level of control for all diseases was good. T2 applications were made during May, with only a few of the more backwards crops left to treat. The high use of fungicides this spring will have increased the cost of inputs to most crops this season. Crop nutrition and other comments Planned fertiliser applications were all made on time this year. There were some areas where ammonium sulphate availability was limited earlier in the season, these crops started to show sulphur deficiency symptoms, but these have been resolved following delayed applications. Lodging is a real concern this season, with thick, forward, tall crops common. There are occasional reports of small areas of fields lodging following heavy rain over the bank holiday. Plant growth regulators were applied on time in most at risk crops, with high risk crops treated with additional products at the flag-leaf stage. Winter barley Growth stages Winter barley crops have typically completed ear emergence (GS 59) and are midway through flowering (GS 65). The most forward crops have completed flowering and are starting milk development (GS 71). The planting date of winter barley was fairly typical and as a result development is also in line with, or only slightly ahead of recent years (Figure 3), the exception being the backward crop of

8 Figure 3 Winter barley growth stage comparison 2014 with previous years and the average, showing proportion of crop at each growth stage. Weeds The overall level of weed control in barley was relatively good, other than crops affected by black-grass (see Black-grass an increasing challenge above). The only control option left for black-grass at this late stage in the season is to destroy badly affected parts of crops to reduce seed return. However, given that fewer crops of winter barley are grown on bad black-grass land this is less of a problem than in wheat. Pests Pest levels tend to be very low. There are occasional reports of aphids and the odd crop shows symptoms of BYDV, but it is not widespread or serious. Disease The main diseases of note remain rhynchosporium and net blotch and these are generally being controlled by planned fungicide applications. The varieties Cassia and Saffron in particular, have high levels of rhynchosporium. The disease is most commonly a problem where winter barley has followed spring barley as a consequence of last years enforced rotation changes due to the weather. Spring barley volunteers in the crop are often carrying high levels of rhynchosporium and are a source of infection. There is plenty of stem based browning including eyespot. Ramularia risk is also high in Scotland. Crop nutrition & other comments Lodging is a real concern this year, with a higher than normal proportion of crops that are thick and lush and therefore at high risk. Most farmers applied early growth regulators at the GS31/32 timing, but only the highest risk were treated with a second PRG treatment at GS37. However, recent rapid growth could put those untreated crops at increasing risk. 7

9 Spring barley Drilling progress and growth stages Drilling progress 99% drilled. Only 3% of the total area was drilled in May with most of the crop already drilled in March and April (Figure 4). The May drilled crops in England were often late decisions on replacing black-grass infested crops or following first cut grass silage. Some of the May drilled crops in the east went into dry seed beds and suffered poor emergence as a result, however most crops have germinated and emerged rapidly with few problems. Figure 4 Spring barley drilling progress comparison with previous years ( ) The majority of crops (46% of area) were at first node detectable (GS 31) by the end of May, with the most forward early drilled crops (5% of area) at boots swollen (GS 45). There were occasional late drilled crops still tillering (GS 21-28). Early sown crops on light land have grown well through the spring and have thick lush growth. Agronomy There were flushes of annual broad-leaved weeds during May, but herbicide applications were effective, controlling both grass and broadleaved weeds. Where spring barley has been used as part of a switch to spring cropping to manage blackgrass there are reports of some high populations of spring germinated black-grass that have proven difficult to control and some patches will require patch treatment with glyphosate to prevent seed return. Some late wild oats will be treated in early June. In Scotland, crops received pre-emergence herbicides to target annual meadow grass. There were few pest problems evident during May, except in regions where spring barley is following grass, where leatherjackets were a problem in some crops. 8

10 Winter oats T1 fungicides were applied as crops reached 1-2 nodes (GS 31-32), typically in the second half of May. These were targeting rhynchosporium which is present in susceptible varieties. Early planted crops with high plant populations on heavier land have been treated with PGRs to minimise the risk of lodging. Growth stages The majority (45%) of crops have reached or exceeded boots swollen (GS 45), with the most forwards crops midway through ear emergence (GS 55). More backwards crop have the second node detectable (GS 32). Weeds Annual broad leaved weeds such as cleavers, charlock and poppy were controlled earlier this month at GS With autumn herbicides working well, the spring germinating weeds have been relatively easy to control. Competitive crops and thick canopies have aided weed control, meaning most crops have low levels of broadleaved weeds present. However, grass weed control is more of a challenge with black-grass and wild oats starting to become visible in affected crops. The grass weeds are less widespread in oats due to site selection. Pests No issues. Disease Mildew levels are low and have generally been controlled by T1 fungicides. Occasional spots of crown rust were reported mid-month, but most were well controlled by T1 fungicides. Spring oats Drilling progress and growth stages Drilling of spring oats is now complete. Typical crops have 1-2 nodes visible (GS 31-32), with the most forward crops having the flag leaf fully emerged (GS 39) and some of the latest drilled crops still tillering (GS 25). Agronomy Post-emergence herbicide applications were made during May as required, mostly targeting broad-leaved weeds. Good crop canopies will aid control. Slugs have occasionally hampered establishment of late drilled crops, especially on heavier soils in the wetter regions (e.g. West Midlands). On thicker crops mildew is evident, and has required treatment as crops reach GS All nitrogen applications were completed during May. Winter oilseed rape Crop development Most crops are in good condition going into June with excellent pod set. At the end of May, oilseed rape crop development is more advanced than recent years (Figure 5), although similar to Typical crops are nearing the end of pod development, with 20% of crops having reached or exceeded 50% of pod set (GS 5,5) and 72% of crops having reached or exceeded 100% of pod set (GS 5,9). Very forward crops have full 9

11 size, green seeds (GS 6,3). Occasional backwards crops are at late flowering (GS 4,5). Figure 5 Comparison of oilseed rape growth stages at the end of May, Weeds Black-grass control has generally been good, with early (late October/November) propyzamide and carbetamide applications, although some later applications were missed due to wet conditions in December/January, leaving higher populations of black-grass. Where black-grass is a particular issue in fields some growers have decided to spray off the worst affected areas to try and reduce seed return the following season. Weeds such as thistle and mayweed are present in the base of crops, but large, thick canopies have helped to suppress weed growth. Lack of frosts and mild weather over the winter has meant that charlock has been poorly controlled and has been reported at high levels in some crops. Pests Low numbers of pollen beetles are present. There have been a few reports of seed weevil damage to pods, although overall numbers are low. Insecticide treatments have been applied to control seed weevil where necessary. Aphid numbers have remained at low levels. Disease Light leaf spot infection was widespread, but has generally been well controlled by the fungicides applied in the spring. 10

12 Sclerotinia levels are currently low, and most crops have received a single fungicide application. Where sclerotinia risk was deemed high crops have received a second fungicide treatment. Crop nutrition and other comments Nitrogen and sulphur applications have been completed. Nitrogen applications were carefully managed, particularly on large, thick canopies to reduce lodging risk. Where nitrogen applications were made early, some crops are very tall and at high risk of lodging in the case of bad weather. Spring oilseed rape Drilling progress- 99% of intended area of spring oilseed rape sown Crop Development Crop development of spring oilseed rape has been variable, depending on drilling date. Typical spring oilseed rape crops (36%) have two to four true leaves (GS 1,2 to GS 1,4). Very forward early drilled crops are at yellow bud (GS 3,7). Susan Twining Sarah Wynn Jack Watts ADAS Boxworth Business line: Mobile: susan.twining@adas.co.uk ADAS Boxworth Direct dial: sarah.wynn@adas.co.uk HGCA AHDB Office: Mobile : jack.watts@ahdb.org.uk 11