The Status of Native Plant Species in Maryland

Maryland Department of Natural Resources
Releases Report on the Status of Native Plant Species

The MD DNR just released an 80-page document entitled Maryland Botanical Heritage Work Group Report (January 15, 2014). The report details the richness of Maryland’s native flora and explains how a small State is home to such a diverse range of plant species. The report explores why certain native plants and their associated habitats have become scarce, and recommends solutions.


The document is a quick read and very interesting. The sources of complexity in Maryland flora have to do with disjunct and peripheral plant species, singular plant and regionally endemic plant communities and then continuing discovery. The report goes into detail regarding the devastation from the overabundance of whitetail deer and biological invasion of non-native invasive plants.

Maryland has 2,500 plant species, with 710 (28%) considered rare, threatened and/or endangered (RTE).

  • Maryland is the fifth-most densely populated state in the nation.
  • It took three centuries to develop the first 650,000-acres of land in Maryland and the last 40-years to develop the next one-million acres.
  • Of the 710 RTE species, 100 are considered historic or extripated, having not been seen in over 20-years.
  • Many wildflower species are becoming uncommon, such as the pink lady’s slipper.
  • A large number of RTE species require frequent disturbance (early successional habitat such as power line clearing).
  • Deer populations are higher than at any other time in history.
  • We have a marked decline of wildflowers, songbirds and tree seedlings due to deer.
  • Once freed from competition by native plants, invasive non-native plants become established.
  • On a typical day in Montgomery County, five motorists strike deer.
  • One in every 141 Maryland motorists will have a deer collision in the next 12-months.
  • The average deer density in Maryland is 30 per square mile and 95 in suburban areas.
  • Portions of Howard County have up to 200 deer per square mile.
  • If healthy forest regeneration is your goal, you can only have 8 to 20 deer per square mile.
  • Deer density greater than 15 per square mile have deleterious effects on the forest ecosystem.
  • Increased hunter access is necessary.
  • 40% of Maryland RTE species are threatened by one or more non-native invasive plants.

I particularly enjoyed the chapter entitled Maryland’s Unique Biodiversity on pages 13 through 21.