During every township survey there are unexpected finds, identification problems, and discoveries of species with broader significance or interest. Following are some of these findings for New Garden Township. Note: “ENA” refers to Exceptional Natural. Area. (See next chapter.) “CC”, or Coefficient of Conservatism is categorized as follows:
- 0 to 3 represents plants with a high range of ecological tolerances, found in a variety of communities.
- 4 to 6 represents plants with an intermediate range of ecological tolerances, usually associated with a specific plant community.
- 7 to 8 represents plants with a narrow range of ecological tolerances or associated with an advanced stage of plant community succession.
- 9 to 10 represents plants with a high degree of fidelity to a narrow range of habitats.
Aplectrum hyemale Puttyroot – Rare – CC=7
Tipularia discolor Cranefly orchid – Rare – CC=6
These two orchids have an unusual life cycle in that they leaf out in late fall and then die back during the next growing season, flowering infrequently in mid-spring and mid-summer, respectively, after their leaves have withered away. Puttyroot occurs occasionally in the lower White Clay valley and Cranefly Orchid is becoming more common in southern Chester County. Due to weather and other circumstances little time was spent surveying when they would have been most visible. However is it likely both occur in the Township, as both grow in neighboring municipalities.
Carex pedunculata A sedge – CC=8
The small cluster of Carex pedunculata along White Clay Creek was not seen in flower, so the identification was not confirmed, but its habitat and vegetative characteristics matched those of populations upstream in Franklin and London Britain Townships. This sedge was not previously known from southern Chester County, and is considered extirpated in Delaware and rare in Maryland.
Decodon verticillatus Water-willow – CC=8 (ENA 14 – Broad Run pond)
Bolboschoenus fluviatilis River bulrush – CC=9 (ENA 12– Somerset Lake)
These two obligate wetland species are not listed in the Flora Atlas for Chester County (1993), although they are common nearby on the Coastal Plain. They might have been planted, but more likely were introduced by waterfowl.
Desmodium laevigatum Smooth tick-trefoil – Undetermined – CC=4 (ENA 9)
Two populations of this increasingly uncommon but showy-flowering member of the bean family were observed in 2007 at the airport; the first, a few small plants in the southeast along the edge of the woods, plus a larger population in the northwest below the runway. Runway expansion since then may have destroyed the larger population (due to safety issues during construction this area was not examined in the most recent survey), and the smaller population was not seen during the survey. There is suitable habitat still present, so the population should not be considered extirpated. Several other less-common species were in the path of the expansion.
Eurybia macrophylla Bigleaf aster – CC=5
Eurybia schreberi Schreber‘s aster – CC=5
These two asters are difficult to tell apart without flowers. A probable population of each was seen in the Township, but not in flower, so the identification was not positive.
Isoetes engelmanii Quillwort
A single plant of this unusual and often easily overlooked ally of the ferns was found in wet springy woods near the east edge of the Township. It has always been an uncommon plant in Chester County, and was specifically mentioned to occur “near New Garden” in Flora of Chester County.
Poa autumnalis Late bluegrass – Endangered – CC=7
A potential population of late bluegrass was found in the Egypt Run watershed too late in the season to positively identify. This grass occurs sporadically along the White Clay corridor, and would be expected to occur in the Township.