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Marsh ragwort (Senecio aquaticus) is as toxic plant not acceptable in managed grassland. Two trials show different options for the control. Selective timing of cutting, mechanical weed control, fallowness and herbicide treatment are effective management practices. The results also confirmed the essential need for a integrated management system for the sustainable control of marsh ragwort.

Loose silky-bent grass (Apera spica-venti) is one of the most important grass weeds in Bavaria. Effective chemical weed control is essential to prevent loss of yield and harvest quality in winter cereals. Crop rotations with more winter cereals and reduced soil cultivation caused a higher infestation of loose silky-bent in arable farming regions. Effects of herbicide resistance were observed since the last 15 years. Herbicide resistance of loose silky-bent is well observed by the official plant protection service of Bavaria. A wide experience of resistance tests shows the development of resistant loose silky-bent grass and provides an opportunity for future prospects in resistance dynamics.

Black-grass (Alopecurus myosuroides) is one of the most important grass weeds in Bavaria. Chemical weed control with high efficacy is very important in crops like winter cereals, oilseed rape and maize. Crop rotations with more winter cereals, reduced soil cultivation and e.g. contract harvesting enhanced distribution of blackgrass in arable farming regions. Effects of herbicide resistance were observed since the last 20 years. The blackgrass herbicide resistance is well observed by the official plant protection service of Bavaria. A wide experience of resistance tests shows the development of resistant black-grass and provides an opportunity for future prospects in resistance dynamics.

In 2011, a long-term field trial started in a winter wheat monoculture at Pettenbrunn, north of Freising, to examine the population and resistance dynamic of black-grass (Alopecurus myosuroides). Four different herbicide regimes and two different tillage methods were used as test factors. The two tillage methods were differentiated by a ploughing vs. non-ploughing primary soil tillage treatment. For the purpose of surveying of black-grass, the density of black-grass plants and seed heads in the treatment areas and in untreated control plots was assessed. In addition, a biotest to examine the herbicide resistance status was carried out using seed samples from untreated control areas. The results of the plant density survey and the resistance examinations are presented for the experiment period 2011 to 2015 and evaluated statistically on the basis of a ranking analysis. With regard to the development of the plant density of black-grass, the type of tillage had a significant influence. The herbicide regimes tested had a significant influence only on the number of seed heads in the treated area. In the factor combination, the method of tillage caused significant differences in plant density. In addition, there were also differences between the herbicide regimes within the non-ploughed plots. The resistance examinations showed a significant influence of the tillage method, while no differentiation emerged between the herbicide regimes. Specific differentiation occurred in the factor combination of tillage and herbicide regime. For the herbicides tested for resistance, significant differentiation occurred between the individual active ingredients and mode of action groups. The results show a development of the population dynamic and herbicide resistance in connection with the test factors, which are obviously not concluded and which must be further examined.

The natural phenomenon of run-off and erosion lead to unpreventable pesticide water pollution in case of extreme weather conditions. In this relationship the use of herbicides involves a higher risk than other pesticides because of the specific terms of application. Directive 2009/128/EC for the sustainable use of pesticides aspires to enhanced water protection. German national action plan contains quantitative objectives which require strong reduction of water pollution by run-off and erosion of pesticides and accordingly herbicides. The European TOPPS prowadis project developed a consolidated and basic diagnosis concept for the first time to determine the field specific run-off risk. Compatible mitigation measures were linked to specific risk scenarios. Risk diagnosis and suitable mitigation measures determine best management practices for the prevention of run-off and erosion. Different new diagnosis methods and the implementation are presented. Further documents and information are available on the web [http://www.topps-life.org/].

The efficacy of different ALS-inhibiting herbicides for the control of brome species (Bromus spp.) was tested in three field trials in the year 2010 – 2012 in the region of North-West-Bavaria Franken. As a result of the trials the standard herbicide Attribut (Propoxycarbazone) was confirmed for the control of brome. In case of infestation with brome and black grass the herbicide Broadway (Pyroxsulam) offers a certain control of both problematic grass weeds. This illustrates the high dependency of sufficient brome control in winter cereals on the effectiveness of specific ALS-Inhibitor herbicides. Because of the high risk of herbicide resistance to ACCaseand ALS-inhibiting herbicides in brome, integrated weed management is essential for the sustainable control of brome in winter cereals, respectively winter wheat.

Five field trials were carried out from 2010 – 2012 on three different locations. The trials conformed high requirement of effective weed control by planting poplar and willow short rotation coppice (SRC) on arable area. The selectivity of different pre-emergent and post-emergent herbicide treatments was tested. Further trials focused on sufficient and long-standing herbicide efficacy of tank mixture and sequence treatments. As results of these trials it is advisable to use proper soil active herbicides like Artist, Cadou SC, Sencor WG, Spectrum, Spectrum Plus or Stomp Aqua as pre-emergent tank mixture treatment after planting of poplar and willow SRC. Aramo and Lontrel 100 can be used as post-emergent treatment for control of specific weeds. We intend to register the successful tested herbicides for minor use in poplar and willow SRC under licensing referred to Art. 51 regulation (EC) no 1107/2009.

The plant protection service of Bavaria and Baden-Württemberg conducted from 2010 – 2013 a field trial program on different locations for the development and evaluation of chemical weed control methods in soybean. In this trails the use of herbicides enabled a yield of +4 dt*ha-1 respectively 118 % in comparison to untreated control. The selectivity of herbicide applications was uncomplicated except for treatments with inclusion of Pendimethalin. Cleavers (Galium aparine) and black bindweed (Polygonum convolvulus) were harder to control than other common weeds. Cockspur grass (Echinochloa crus-galli) was also insufficient controlled, but there was no addition use of specific grass weed herbicides in the application programs. The total weed control efficacy for all treatments was proved in a range of 84-97 %. Fat-hen (Chenopodium album) as the most important weed in soybean could be controlled by specific herbicide treatments in a range of 83-99 %. For integrated weed management it is necessary to consider the site specific weed spectrum, herbicide specific efficacy and the amount in respect to the local soil and weather conditions. As a result of the trials it was possible to authorize the minor use of three further herbicides in soybeans. In consequence there is a comfortable variety of different herbicides in soybean available.

Different herbicide treatments were tested in the year 2010 – 2013 at eight locations in the north-west of Bavaria in Franken to control herbicide resistant black grass (Alopecurus myosuroides, Huds.). Application of Atlantis (Mesosulfuron + Iodosulfuron + Mefenpyr) was essential for the control of black grass in winter wheat. Combination with other herbicides was also in focus of the trial program as different treatment methods, application timing, application sequences, herbicide rate and the use of adjuvants. As a result of the trials sequence applications were more effective than single applications. The use of soil active herbicides in autumn and spring application of Atlantis was one of the best solutions to control resistant black grass in winter wheat. Reduced rate of Atlantis have to be compensated by addition of appropriate adjuvants. Higher level of resistance depends on implementation of integrated weed management to serve economic wheat production.

Glyphosate is an important herbicide for the control of weeds and volunteer crops in production systems with conservation tillage or direct drilling. For a feasible timing of the glyphosate application it is essential that the following crops are not aggrieved by soil uptake of glyphosate. In field trials over several years it was confirmed that a usual application with 1800 g/ha glyphosate poses no risk for the growth of subsequent corn or winter wheat. Low yields could be caused by different soil management techniques such as conservation tillage or direct drilling and the preceding crops. Treatments with a dosage of 1800 – 7200 g/ha glyphosate with a time lag of 23 – 10 day before mulch-sowing, resp. 1 day after direct drilling had no influence on the growth and yield of following corn and winter wheat. Based on the results of these field trials it can be confirmed that glyphosate is a save herbicide for weed control in production systems with conservation tillage or direct drilling.

Cranesbill species achieved a strong expansion with high infestation rates in German arable farming systems in the last years. They evolved from rare to hard-to-control weeds. Crop rotations with a high percentage of winter oilseed rape and maize are mainly affected. Current herbicides show only a limited efficacy against cranesbill species in these crops. Data from field trials and laboratory tests show the potency of chemical control measures in cereals, winter oilseed rape and maize. The experimental results are summarized and recommendations for the chemical control of cranesbill in arable farming discussed.

Alopecurus myosuroides and Apera spica-venti are the most important grass weeds on arable land. For many years, these grass species have shown a development of herbicide resistant biotypes and populations. Appropriate field techniques and herbicide control are absolutely essential for the prevention and limitation of resistance development. The official plant protection service has an decisive task as a neutral and independent institution for suitable anti-resistance strategies based on herbicide management. Basic recommendations and principles are presented for appropriate cropping strategies and the implementation of suitable, specific herbicide management techniques for the avoidance of resistance. Specific aspects of the control of Alopecurus myosuroides and Apera spica-venti in different regions of Germany are discussed. The presented concepts are the basis for advice for the plant protection industry and the agricultural trade.

Black-grass (Alopecurus myosuroides) is one of the most important grass weeds in Bavaria. Chemical weed control with high efficacy is very important in different crops. Crop rotations with more winter cereals, reduced soil cultivation and e.g. harvesting by private contractors caused a higher distribution of black-grass in arable farming regions. Evolution of herbicide resistance was observed during the last 20 years. Black-grass herbicide resistance is well monitored by the official plant protection service of Bavaria. A wide range of resistance tests show the development of resistant black-grass and provide an opportunity for future prospects in resistance dynamics.