In the study, the following questions were explored: Which plants did humans gather in prehistoric times? When did the first cultivated plants make their initial appearance, and where did they come from? How did farming develop after its adoption?
To find answers to these questions, ancient plant remains, such as nutshells, seeds and grains found at archaeological digs were analysed.
Finland was settled roughly 11,000 years ago after the ice cover receded. Today, Finland is covered mostly by coniferous forest, including pine and spruce.
Prior research has focused on the animals that Stone Age people hunted. Based on the recently completed study, a number of plants were also utilised in Stone Age Finland. For example, hazelnuts and water chestnuts were gathered for food, and they in fact grew further north than today. At that time, the average temperature was a couple of degrees higher, and deciduous trees grew in larger numbers in the forests of the region. These days, the northernmost regions where water chestnut grows are approximately 1,000 kilometres further south.
Agriculture was introduced to Europe by populations migrating from the Middle East. During their journeys, farming cultures underwent change. Hunter-gatherers had an impact on the human DNA, while material culture was transformed and the number of cultivated plants decreased the further north humans travelled.
Earliest grains found on Åland
In the study, the oldest barley and wheat grains in Finland were found on the Åland Islands, located in the Baltic Sea between Finland and Sweden. Based on radiocarbon dating, these grains proved to be roughly 5,000 years old, making them a thousand years younger than those found in the area surrounding Stockholm and 2,500 years younger than those found in Central Europe. At the time, hunter-gatherers specialised in hunting seals and representing the Pitted Ware culture moved to the islands from the area of today's Stockholm. They appear to have adopted agriculture from farmers who had spread to Scandinavia 6,000 years ago. The finding was a surprise, as hunter-gatherers have very rarely been demonstrated to have adopted the art of cultivating land.
After the first farming wave, there is roughly a thousand-year break in the incidence of crops in Finland, even though the Corded Ware culture, spread through Estonia, did practise animal husbandry.
The cereal grain discoveries indicate that farming became an established practice in the south-west coastal area of Finland only from the beginning of the Bronze Age, approximately 3,500 years ago. Based on the shape of burial sites and material culture, this farming culture arrived from Sweden.
Barley as the key cereal crop
Due to its adaptation to colder climates, barley was the most important cereal crop throughout prehistory. In the early Common Era, the plants cultivated in fields also included emmer wheat, rye and common wheat, as well as flux and hemp. Slash-and-burn cultivation has been considered the oldest cultivation method employed in Finland, but on the basis of the weeds found in this study and previously analysed discoveries in ancient fields, it appears that field cultivation was adopted no later than approximately 1,500 years ago.
In addition, plant gathering continued even after the adoption of farming. However, cereal crops seem to have replaced carbohydrate-rich wild plants, such as yellow water lily, the seeds of which contain approximately 80 grams of carbohydrates per 100 grams. The use of wild strawberry, raspberry and juniper, among others, continued, potentially for their taste as well as for their medicinal effects.
The ancient hunter-gatherers of northern Europe adapted to their changing surroundings and took advantage of the plants available to them in many different ways. The introduction and establishment of farming, which took place later, constituted a development of thousands of years affected alternately by migrant waves and local developments.