Bur oak typically grows in the open, away from forest canopy.
For this reason, it is an important tree on the eastern prairies, often found near waterways in otherwise more forested areas, where there is a break in the canopy.
It is drought resistant, possibly because of its long taproot.
At the end of the growing season, a one-year sapling may have a taproot 1.37 m (4 ft 6 in) deep and a lateral root spread of 76 cm (2 ft 6 in).
The West Virginia state champion bur oak has a trunk diameter of almost 3 m (10 ft).

Large bur oaks, older than 12 years, are fire-tolerant because of their thick bark.
One of the bur oak's most common habitats, especially in Midwestern United States, is the oak savanna, where fires often occurred in early spring or late fall, especially in hill country.
Without fires, bur oak is often succeeded by other tree and shrub species that are more shade-tolerant.
Older bur oaks may survive in dense woodlands for 80 years, until they are weakened by wood-rot fungi in the lower branches killed by shade, and by 100 to 110 years, they are often snapped by wind storms.
Bur oak typically grows in the open, away from forest canopy. For this reason, it is an important tree on the eastern prairies, often found near waterways in otherwise more forested areas, where there is a break in the canopy. It is drought resistant, possibly because of its long taproot. At the end of the growing season, a one-year sapling may have a taproot 1.37 m (4 ft 6 in) deep and a lateral root spread of 76 cm (2 ft 6 in). The West Virginia state champion bur oak has a trunk diameter of almost 3 m (10 ft). 
Large bur oaks, older than 12 years, are fire-tolerant because of their thick bark. One of the bur oak's most common habitats, especially in Midwestern United States, is the oak savanna, where fires often occurred in early spring or late fall, especially in hill country. Without fires, bur oak is often succeeded by other tree and shrub species that are more shade-tolerant. Older bur oaks may survive in dense woodlands for 80 years, until they are weakened by wood-rot fungi in the lower branches killed by shade, and by 100 to 110 years, they are often snapped by wind storms.
Quercus macrocarpa