The changing natural world at our doorsteps | Illustration and text by Patterson Clark
March 8, 2011
March of the nest traps
| The first plants to leaf out may not be the best for birds to lay eggs in.
Even though winter isn't quite finished with us yet, two invasive plants have been getting a head start on spring, responding to brief warm spells by erupting with shoots of new leaves.
Japanese honeysuckle, which still bears some of last year's leaves,
and multiflora rose are well ahead of native plants in sprouting. They will soak up as much direct sunlight as they can before overhanging trees leaf out and pull down the shades.
When spring arrives, the thick and early growth will attract robins and
cardinals -- but the birds make a poor choice if they build their nests in these nonnative weeds. In urban areas, predators are twice as likely to disturb nests built in multiflora rose and Japanese honeysuckle as they are to attack nests built in native vegetation.
That may be because the two invasive plants tend to grow lower to the ground and are in some way structurally easier for predators to access. Also, predators may have learned to check honeysuckle and rose more often for hapless nesters.