Since 2005, prescribed by law, the land offices and the Institute of Geodesy, Cartography and Remote Sensing (FÖMI) have been supporting the official prevention and monitoring of this rapidly spreading allergenic weed (ambrosia or ragweed). The land offices started to work on this new task with much energy. The agrarian experts of the land offices took over those GIS tools and programs for use that were applied earlier by land surveyors only.

Ambrosia vs. authority: tasks, methods and results of the land management in preventing and monitoring ragweed

 Attila Mezei
senior counsellor
Ministry of Agriculture and Rural Development,
Dept. of Land Administration and Geoinformation

Since 2005, prescribed by law, the land offices and the Institute of Geodesy, Cartography and Remote Sensing (FÖMI) have been supporting the official prevention and monitoring of this rapidly spreading allergenic weed (ambrosia or ragweed). The land offices started to work on this new task with much energy. The agrarian experts of the land offices took over those GIS tools and programs for use that were applied earlier by land surveyors only. 
As first in Hungary, but also in Europe, electronic data transfer was developed between the countrywide networks of two specialized authorities; this data transfer has probative force and resulted in official sanctions. The minutes taken by the land office staff during the onsite ragweed checks are forwarded for further action to the plant protection authority through the central server of the Ragweed Information System, developed and managed by FÖMI. Based on the developments of 2008, all sanction measures could be performed by using this information system. It is a significant achievement that the duration of the ragweed prevention procedure decreased to one fifth compared to the pervious one.  
According to the law, the cutting of ragweed is the duty of the farmers (owners or users). The new regulation does not mean of course that the staff participating in the prevention of common interest would cut down ragweed for the farmers; neither the land management, nor the plant protection authority has capacity for that job.
Seemingly, the collective thinking is to be changed basically; that would lead to the decrease of ragweed pollen concentration. The land owner/user is expected voluntarily to cut down the ragweed before flowering, obeying the law and out of responsibility for the health of other people too.
Ragweed has been spreading all over Europe and in many other countries of the world, conquering more and more territories. The significance of ragweed is shown by the fact that in 2008, two international conferences were dealing with it, mostly searching for the reason of its aggressive spreading.
The first ragweed conference was held in Hungary, in September 2008, hosted by the Hungarian Academy of Sciences. The ragweed researchers of four continents and eleven countries described and discussed their results considering the global warming, the growing carbon-dioxide content of the atmosphere and the herbicide resistance. Also the experts of health care, aerobiology and remote sensing added their experience. It became evident that at the moment no overall successful solution is in hand that would stop spreading of ragweed and its aggressive pollen production, though promising experiments are going on in some countries.
The second conference took place in Aix-les-Bains, France on 21 November. The spreading of ragweed has been causing ever growing problems in France too, in spite of the fact that strict legal regulation stepped into force in the past couple of years.

Let us see, what have land administration done for ragweed prevention in 2008, apart from the efforts by the population and the civilian organisations.
230 employees of the 19 country land offices plus the Budapest Land Office and the district land offices supervised by them spent altogether 3043 workdays from 1 July till 20 October 2008 performing on-the-spot inspections. During this period, they investigated and identified 11336 ragweed spots (total size of 19411 hectares) and forwarded the official records to the plant protection authority for further action.
Compared to the data of the previous year, the number of ragweed spots identified by the land offices increased by 73%, while the size of the infected area increased by 62%.
The land office staff have gathered significant experience of applying technical devices (PDA-GIPS configuration, allowing them to work quicker), and also in using electronic data recording and data transfer functions.
Though the identified ragweed spots mean some percents of the heavily endangered arable land areas of the country, but under the current personal and technical conditions, this result was close to the maximum amount of data to be processed in this procedure.  Considering that the ragweed inspectors of the land offices also have other tasks to perform, and the cars of the office are not available any time, there were altogether two days left for field work.
In 2008, a priority job was to check the stubble-fields producing extraordinary amount of pollen; land offices identified 4451 ragweed sports of an area of 9272 hectares. The more intensive checking in the coming years is justified by the fact as well that while 23% of all identified ragweed spots was on stubble-fields, this meant 72% of the whole area to be inspected. During the harvest period of grain crops there were heavy rains that favoured the growing of ragweed and also delayed the stubble-stripping. But following the warning by the land offices, the farmers took more care about the stubble-fields and put several questions: before which stage of development of ragweed could they complete the cutting to avoid the fine.
According to the reports by the land offices, the amount of ragweed was bigger in 2008 than before. Especially the sunflower-fields were heavily infected. The producers of field crops state that in many cases it is “cheaper” to pay the plant protection fine than apply efficient but expensive agricultural engineering methods or pesticides. This can be the reason of the increased pollen production. Therefore the land offices are expecting the introduction of the cross compliance system, in which the farmers will be made more interested in keeping the root crops and stubble-fields weedless.
The abandoned suburban areas and the jointly owned land parcels keep on creating problems. In general, it can be stated that the farmers and land users are taking more care of the parcels in those areas where the production is more profitable.
Due to the experience gathered in 2008 and the joint on-the-spot checks, the accuracy of the “danger maps” by FÖMI has increased: this was the feedback by land offices. At the meeting while evaluating the results of 2007, a proposal was born about joint field checks to be performed by the employees of the land office, the Ministry and FÖMI. A field check was performed in Bács-Kiskun County, within 10 days after the publication of the “danger map”. Using the map, during two on-the-spot inspections, an area of about 300 hectares was recorded by the competent land office.
The results of the joint checks confirmed that in the official procedure, the use of danger-maps is important, and also that the efficiency of the inspection can be increased by a field check performed as soon as possible after the publication of the map.
In 2008, FÖMI has produced the map of the regions most heavily endangered by ragweed. The maps have been updated 3-5 times from mid July in the most endangered areas (1878 spots of 9529 hectares altogether, concentrated mostly on the stubble-fields heavily infected after the grain crop harvest).
The data of these „danger-maps” of FÖMI prepared by remote sensing methods are available for the wide public too. The information is accessible on FÖMI’s official homepage offering countrywide overview on ragweed-infected areas and the involvement of physical blocks of the Agricultural Parcel Identification System too. The information has been produced on the basis of the land office field check data and of the danger maps produced by remote sensing methods.
Special thanks are due to dr. Gábor Mikus, Head of the Department of Remote Sensing Applications in Agriculture (FÖMI) who made the necessary data available for us.