Erechtites hieraciifolius (L.) Raf. ex DC.

• Region

  North America

• Country

  United States of America

• State/Province

  New York

• County/Municipio

  Bronx Co.

• City/Township

  New York City

• Locality

  The New York Botanical Garden, at edge of Lower Twin Lake

• Elevation

  Alt. 18 m. (59 ft.)

• Coordinates

  40.8672, -73.8765

• Distribution

  Map all specimens of this taxon

The New York Botanical Garden
Plants of U.S.A.

Asteraceae Erechtites hieraciifolius (L.) DC.

det. M. Nee, 2012

New York State, Bronx Co., Bronx, The New York Botanical
Garden, at edge of lower Twin Lake.

40°52’02”N, 73°52’35.5”W alt. 18 m.

Area cleared last year of brush and some trees, grown up to
mostly native weedy species such as Phytolacca americana,
lmpatiens capensis, Solarium ptycanthum, Cyperus, Polygonum
punctatum, Eupatorium rugosum, also with Persicaria
extremiorientalis.

Common, erect, single-stemmed annual herbs, a few shaded and
only 0.4 m tall, unbranched and with only a few heads. This plant
one of the largest ones, 2.2 m tall and branched above stems to 2.5
cm in diameter. Leaves all sessile, variable in shape and size, the
ones on the lower stem shallowly dentate, the middle ones where
branching beginning are the largest and most deeply lobed, the
upper ones again smaller and only dentate. A large plant like this
has heads in various stages, always inconspicuous and appearing
yellow-green from a distance except when with mature white
pappus; phyllaries yellow-green. Florets inconspicuous, appearing
yellow-green except when examined closely; outer (pistillate)
florets usually pale yellow-green, but sometimes the upper corolla
tube pale pink; inner (perfect) florets with the anthers pink or
reddish at some stages, and the corolla lobes definitely pink;
flowers visited by Apis mellifera and a large and a small
bumbelbee, but only probing the florets at certain stages, alighting
on the head and probing the florets, “walking” around the head
once or twice during the process before moving on to another
head. After finishing with one plant, they usually examine a few
more heads on that plant, then fly to another and repeat the
process. The bees must be using visual clues as all heads seem to
be odorless. Mature heads always looking disheveled, even after a
week with no rain, the old central florets clotted and matted and
keeping the pappus together (unlike symmetrical heads of free
fruits of, e.g., Lactuca or Tragopogon), seemingly an inefficient
way of dispersal.

Coll.: M. Nee 59446

15 Sept. 2012

02075160