Plant

Description
Plants are highly informative in archaeological research. The branch of archaeobotany (investigations of plant remains from archaeological contexts), for example, deals with the reconstruction of vegetation and agricultural history. Plant remains can shed light on cultivation methods and diet habits in the past as well as provide information on climate change. Archaeometric methods mainly refer to the dating of plant remains and thus their use by humans. Plant macro remains from peat bogs, for example, can — in addition to climatic conditions — provide information about the formation and temporal existence of bogs, to mention just one example from the geosciences. Here, macro remains (seeds, wood residues, roots etc.) or micro remains (pollen etc.) can be analyzed.
Both modern plants as well as ancient botanical remains are important sample materials for isotope analyses. Charred fruits and seeds from archaeological contexts, especially cereal grains, store information regarding the cultivation methods as well as possibly the location of arable lands to cultivate staple crops. Stable carbon isotope ratios depend on water availability. They mirror moisture or dryness of the cultivation sites and may provide information about artificial irrigation.
Stable nitrogen isotope values of cereal grains may increase noticeably due to the application of animal manure for fertilizing arable land and may provide information on agricultural management strategies in the past. Furthermore, cereal grains are important comparative samples for the interpretation of stable carbon and nitrogen isotope data of human collagen. They reflect the isotope ratios at the base of the food chain and contribute significantly to statements regarding human food habits.
Modern plant material is often used as comparative samples for strontium isotope analysis with regard to human and animal mobility. Tree leaves, leaves of shallow-rooted plants or wood document the isotope composition of the biologically available strontium. Their advantage is the possibility of a targeted selection of the sampling sites with regard to their geological conditions as well as an exact documentation of the location by means of GPS. However, there is uncertainty regarding the influence of strontium introduced by humans in the recent past with isotope ratios deviating from natural sources.
Sample properties
14C dating
The sample size should ideally be around 20-30 mg. The samples should be free of adhering sediment. Please contact the laboratory if the sample size is considerably smaller.
Carbon and nitrogen isotope analysis
In order to ensure appropriate preparation of material from archaeological contexts and the representativeness of the sample material, samples for stable carbon and nitrogen isotope analysis should consist of at least 10 cereal grains of the same plant species each.
Comparative samples for strontium isotope analysis
Comparative samples for strontium isotope analysis should comprise approximately the amount of an A5-sized bag per sampling location, washed with distilled water if necessary and dried. Plants shall be submitted along with species information (one species per sample), geographical coordinates recorded by means of GPS and information on the geological conditions at the sampling location, which may be selected specifically to represent a certain geological unit.