This paper investigates the tree motif as a visually recurrent and ideologically charged element in nineteenth-century Northern European landscape painting.

Taking the beech tree in Danish Golden Age art as a point of departure, the study situates arboreal imagery within broader processes of national identity formation. While motifs such as the Danish beech, the German oak, or Mediterranean cypress have long been discussed in symbolic terms, their large-scale visual distribution has not been systematically quantified.

To address this gap, we assemble a corpus of 4,727 nineteenth-century landscape paintings from Denmark, Norway, Sweden, Finland, Germany, and England and apply a prompt-based segmentation pipeline using the Segment Anything Model (Sam3).

With this, 63% of the corpus is identified as containing tree imagery, yielding approximately 27,000 detected instances. From these segmentations, we derive quantitative metrics capturing motif presence, spatial occupancy, compositional distribution, and low-level color and texture features.

The results demonstrate the feasibility of segmentation-based motif analysis for art history and reveal diachronic and regional patterns in tree representation.

The ongoing work explores fine-grained classification of tree species through CLIP-based model adaptation, enabling closer analysis of regional specificity and painter mobility. The study therefore contributes to a computationally grounded account of how ostensibly generic natural elements functioned as national symbols in nineteenth-century visual culture.