Forests, mountains, rivers, and Tirthas, are considered as having no owners. No earth need be bought here for performing Shraddhas.
अटवीपर्वताश्चैव नद्यस्तीर्थानि यानि च॥ सर्वाण्यस्वामिकान्याहुन हि तत्र परिग्रहः।