The Dagshelgr Invocation was a custom practiced by the elves, in which they sang and performed planting spells. The influence of the Invocation was supposedly harmful to mortals. It apparently influences all living creatures to find a mating partner.
This was the reason why Du Weldenvarden was filled with trees two to four times the size of normal trees found in other forests. Eragon, Orik, Arya, and their companions heard the elves perform this ceremony near Sílthrim. Saphira expressed loneliness, as there was no other known male dragon to her at that time other than Shruikan. Arya cast a spell on Orik and Eragon to prevent them from being harmed by the magic of the ritual.