Cosmos

on graded rubble of old roadside pullout in white volcanic tuff. This species is largely distinguished with difficulty from C. pringlei by a 2 cm difference in maximum width of the flowering heads which make photo determination impossible and pressed specimen difficult, without careful in-field measurements of live mature heads. In most cases I have placed these similar plants under C. palmer, the slightly smaller and more common of the two species.

on graded rubble of old roadside pullout in white volcanic tuff. This species is largely distinguished with difficulty from C. pringlei by a 2 cm difference in maximum width of the flowering heads which make photo determination impossible and pressed specimen difficult, without careful in-field measurements of live mature heads. In most cases I have placed these similar plants under C. palmer, the slightly smaller and more common of the two species.

partly shaded pine understory on volcanic tuff substrate. This species is largely distinguished with difficulty from C. pringlei by a 2 cm difference in maximum width of the flowering heads which make photo determination impossible and pressed specimen difficult, without careful in-field measurements of live mature heads. In most cases I have placed these similar plants under C. palmer, the slightly smaller and more common of the two species.

in sunny shallow swales, cracks and pot holes on flat portions of the ridge top of exposed rhyolitic tuff forming the Continental Divide This species is largely distinguished with difficulty from C. pringlei by a 2 cm difference in maximum width of the flowering heads which make photo determination impossible and pressed specimen difficult, without careful in-field measurements of live mature heads. In most cases I have placed these similar plants under C. palmer, the slightly smaller and more common of the two species

in sunny shallow swales, cracks and pot holes on flat portions of the ridge top of exposed rhyolitic tuff forming the Continental Divide This species is largely distinguished with difficulty from C. pringlei by a 2 cm difference in maximum width of the flowering heads which make photo determination impossible and pressed specimen difficult, without careful in-field measurements of live mature heads. In most cases I have placed these similar plants under C. palmer, the slightly smaller and more common of the two species

Photo taken in Las Cruces, NM, on 30 Jan 2016. Longest fruit body from base of pappus to base of fruit = 12 mm

on open, grassy, undulating plain in basin along & below eastern Madrean escarpment, among diverse grasses and forbs on coarse volcanic alluvium.

narrow canyon bottom on coarse gravels and sands of volcanic rhyolitic tuff in open area above creek

roadside openings on volcanic soil and gravels

roadside openings on volcanic soil and gravels

roadside openings on volcanic soil and gravels

Cosmos caudatus . Foto: Alexander Rodríguez.

Semillas de Cosmos caudatus . Foto: Alexander Rodríguez.