Plant Biodiversity is Essential for Ecosystems

According to the Vermont Fish and Wildlife Department, Vermont has “over 2,800 plant species. Most of these are flowering plants, but this also includes conifers, ferns, grapeferns, clubmosses, horsetails, quillworts, spikemosses, and bryophytes — mosses, liverworts, and hornworts.” Of these, 1448 are native, and 137 are natives to other regions of the US and have been introduced here. We have over 600 rare and uncommon native plants including 163 on the threatened and endangered list.
Recent research has shown that biodiversity is vital to ecosystem functioning and stability. Ecosystems with higher biodiversity are more resilient to weather and climactic extremes, as well as other major disturbances. Decreases in biodiversity, therefore, raise alarm about the future functioning of our ecosystems and their capacity to recover from extreme events.

Evening Primrose

Plants are foundational to all ecosystems. They shape hydrological systems, put oxygen in the air, recycle nutrients, form and conserve soil, regulate the climate, and provide habitat for animals. As a primary energy base through photosynthesis, they are the base of food chains for all animals.
The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) reported that declining biodiversity is a global problem, occurring at an unprecedented rate. Significant declines in plant biodiversity are being documented in Vermont’s forests, fields, and wetlands, as well. Recent forest health reports from the Vermont Department of Forests, Parks and Recreation show increasing stress from drought, invasive pests, and poor regeneration — clear signs that the state’s ecosystems are under mounting pressure. The drivers of the biodiversity decline in Vermont include climate change, habitat loss, non-native invasive species, deer overbrowse, declining insect populations, and simplified forest structure (even-aged stands).

Green-fringed Bog Orchid

Climate change, by virtue of rising temperatures, changing rain patterns, and more intense weather events, imposes serious threats to plants. According to the Vermont Climate Assessment, (2021) the state is already experiencing warmer winters, heavier downpours, and longer summer dry spells — conditions expected to accelerate ecological change. Warmer winter temperatures decrease winter snowpack, and may eventually eliminate it altogether. Vermont is forecast to have the climate of North Carolina by 2070. Winter snowpack insulates plant roots from ice and heaving. Warmer nighttime temperatures during the growing season prevent plants from recovering from daytime heat stress. Warmer temperatures allow pests and diseases to flourish. Vermont is predicted to lose many plant species due to climate change, especially Sugar Maple.
Recent US Forest Service research indicates invasive species are now a primary driver in biodiversity loss; they interact with climate change to accelerate ecosystem disruption. In Vermont, for example, invasive worms are changing soil composition and reducing leaf litter, pests like Emerald Ash Borer and Hemlock Wolly Adelgid are killing trees, and plants like Japanese Knotweed are creating vast monocultures.

Yellow Lady’s Slipper

According to the University of Vermont, the state loses about 5000 acres per year from development, fragmenting forest blocks. Even where total forest acreage remains relatively stable, recent mapping shows increasing fragmentation and parcelization, which reduces habitat connectivity and biodiversity. The Native Plant Trust estimated that “on average, rare plant species have lost 67% of their known range in the region.”
Deer populations have been allowed to grow to the point where they are eating forest understory, and posing a serious threat to forest regeneration.
Research from the Xerces Society and the University of Vermont confirms that pollinators themselves are declining across the Northeast, with disruptions in timing between flowering plants and pollinator activity, as a result of climate change, further threatening reproduction.

What can you do?

1.  Plant native plants. Replace non native plants, and remove invasives like Japanese knotweed, burning bush, butterfly bush, garlic mustard, buckthorn, Oriental Bittersweet, etc.
2.  Convert as much of your lawn as possible to native plants.
3.  Support policies and actions to tackle climate change ASAP.
4.  In the fall, do not cut down plants. Leave them standing until June to protect pollinators.
5.  Allow hunters to take deer on your property. Support efforts to reduce Vermont’s deer numbers.
6.  When fishing, do not release live worms.
7.  When gardening, do not dump horticultural products in or near the woods.
8.  As much as possible, buy bare root plants.
9.  Do not move firewood from elsewhere.
10.  Keep your lights off at night. Install motion sensing outdoor lighting.
11.  Do not use pesticides. There is no such thing as a pesticide that does not kill beneficial insects.