Growing on the west side of Unterweirachhof farm is an approximately 250-year-old vine of the Weißer Heunischer grape variety, which has been placed under protection as a natural monument. Tradition has it that this vine was destroyed by the French during the pillaging of the courtyard during the Napoleonic Wars in 1809. When the farm was rebuilt in 1810, the vine began to sprout again. The base of the grapevine has a circumference of 106 cm.This formerly widespread grape varietal can now be found almost solely on old stock located on the viticultural fringes. Since it is a winter-hardy variety, it is also said: “From loden skirts and the Heunischer vine, Tyroleans shall never part.”The Fachschule für Obst-, Wein- und Gartenbau Laimburg (College for Fruit, Wine and Horticulture) used seedlings of this Heunischer to include them in the collection of old grape varieties.