Winter Trees and Shrubs: Northern Catalpa awkward botany In autumn, mature catalpa seed pods turn brown and often hang on the tree through late fall and into winter. Today's @marthastewartblog looks at some of the seeds, berries, and cones of Meet My Nature Neighbor: The Catalpa Tree Heartspoken The Northern Catalpa Tree Nebraskaland Magazine Franklin & Marshall Northern Catalpa (Catalpa speciosa)