Quercus oblongifolia | New Mexico
Within its habitat, this is the growth habit you will often see with Mexican Blue Oak (Q. oblongifolia). The rounded canopy is quite striking, and is one of several drought adaptations that Mexican Blue Oak displays, including the blue tint to the foliage, the thick waxy cuticle on the leaf, and a growth habit that maximizes shading to the root system immediately beneath the tree. The height of the canopy above the ground is a function of the type of browsing animal that has eaten the tree historically. In this case, as in many, domesticated cattle were likely the primary determinants of canopy height, and the cattle lose to congregate in the dense shade beneath the tree, a preference which can have disastrous long term effects, as soils beneath the canopy become compacted, and also become toxic from the intense concentration of bovine waste.