One file, one import
Babylon.js loads glTF natively. Import a FoliMesh GLB with SceneLoader.ImportMeshAsync and you get the meshes, materials and textures, with each LOD as its own mesh.
LOD with addLODLevel
Use LOD0 as the main mesh and attach LOD1–LOD3 with addLODLevel at the distances you need. Triangle budgets per LOD keep large scenes smooth.
Instances for forests
The meshes work with Babylon.js instances and thin instances, so you can place thousands of trees cheaply. Export several seeds of a species to avoid repetition.
Realistic or low-poly
Realistic trees come with bark and leaf textures for PBR materials; low-poly assets use vertex colour and need no textures at all.