Baccharis species

Yesterday was the first foray of the new year out into the Cottonwood Gallery.  With construction at the Garden focused on the Heritage Farm railroad and the new Lebanese Garden, we've been able to return more or less to our path through the farm to get to our Nature's Notebook plots.  

We were greeted by the new critters on the farm and some of the old.  Bugsy the horse and the Churro sheep were in their paddocks.  Then, out past the new demonstration garden beds, the Highland cows (coos) and miniature donkeys were grazing.  

We made our observations in good time and, while we were at it, collected material for determining which Baccharis species we have.  I spent a fair piece of time with 3x, 10x and 40x optics once back at my desk.  

• Leaves:  Distally serrate with 3 nerves 
• Involucres:  Obconic to campanulate (upside-down cone or bell-shaped), not hemispheric (half of a sphere, very rounded); staminate ~4 mm, pistillate ~7 mm
• Pistillate florets:  <30
• Staminate florets:  ~20
• Phyllaries:  4-6 mm
• Heads:  Leafy paniculiform (branching on an elongated axis), not corymbiform (somewhat flattened)

All those characteristics align with B. salicina, not B. salicifolia.  

Leaf with 3 nerves and distal teeth

Obconic involucre