Giuseppe Penone: Thoughts in the Roots; José María Velasco: A View of Mexico – review

Serpentine South Gallery; National Gallery, LondonThe arte povera veteran’s passionate celebration of trees risks being eclipsed by the real ones that surround it. And a 19th-century Mexican polymath becomes the first Latin American artist to have a solo show at the National GalleryA tree towers upwards in Kensington Gardens, slender but unimaginably strong, grey boulders perched like vultures among its branches. Another gestures directly to the sky, twigs spreading in eloquent appeal. A t