Ecological Highlights Tour Preview

Welcome to the Ecological Highlights Tour, which will walk you through some of the ways that native plants support a rich, biodiverse ecosystem. There is no accompanying voiceover for this tour; it is intended as a supplement to the main audio tour with synchronized stops.

The entry garden and woodland are full of spring ephemerals, so named for their fleeting visibility (just a few weeks from mid-April to early May). Plants like Bloodroot (Sanguinaria canadensis), Spring Beauty (Claytonia virginica), and Dutchman’s Breeches (Dicentra cucullaria) take advantage of the sun that reaches woodland floors before tree canopies send out their leaves.

Queen bumblebees (Bombus spp.) are some of the season’s earliest pollinators, emerging in concert with the spring ephemerals. Queens hibernate underground during the winter, meaning that their energy stores are greatly depleted once they surface. Ephemerals provide a vital first source of pollen and nectar to the awakening bees, allowing them to build their nests and rear their young.

Climate change is causing plants’ flowering time to shift earlier and earlier as winters shorten. Researchers are still working to understand how severely this will impact pollinator populations, but earlier snow melts have already resulted in a measurable mismatch between bee emergence and flower availability. This means that the plants will have a harder time getting pollinated and bees will have a harder time provisioning their broods. To help support local hibernating bee populations, make sure to include both early and late blooming native plants in your garden!

The Idea Garden displays several examples of native groundcovers. Podophyllum peltatum, the Mayapple, is a fascinating plant with umbrella-like leaves. They can form dense colonies once established and stay about 1-2 feet tall. The spring flowers are showy but open under the leaves; crouching is necessary to view them. The plant produces highly poisonous podophyllotoxins that make them largely unappetizing to most herbivores. However, once the fruit softens and turns bright yellow in late summer, the jelly-like interior is edible to humans and other animals.

Since Mayapple fruits are heavy and stationary, they are totally dependent on animals to move them to new locations away from the original colony. One animal in particular—the Eastern Box Turtle (Terrapene carolina carolina)— appears to be a primary disperser of Mayapple seed. The fruits hang at the perfect height for a turtle to take a bite. This appears to be a doubly adaptive relationship for the Mayapple, as its seeds are much more likely to germinate post-turtle digestion.

Sedges (Cyperaceae) are an overlooked but crucial component of the New England flora, and you can find several species growing in the Curtis Woodland. Sedges are distinct from grasses, and they flower and fruit in the spring while grasses usually bloom in late summer or fall. This means that seed eating birds— ducks, turkeys, grouse, sparrows, etc— have a food source earlier in the growing season. Sedges are a highly popular host plant for caterpillars; Pennsylvania Sedge (Carex pensylvanica) alone can support 36 different species of butterflies and moths. Birds use them for nesting material, small animals live and hide in them, and they stabilize soils with no requirement for fertilizers or irrigation when planted in their ideal location. There’s a sedge for every moisture, lighting, and mowing condition, and they make a wonderful alternative lawn (see our Carex lawn in the Idea Garden).

Many people think of plants as stationary organisms. Individual trees definitely don’t walk from one place to another, but plant populations have evolved numerous mechanisms for getting their seeds from one place to another. Seeds can float on water, drift through the air, be digested and deposited by birds, or be buried and forgotten by squirrels. Some plants, like Jewelweed (Impatiens capensis) produce spring-loaded pods that launch seeds when touched. Others employ a strategy known as myrmecochory, a fancy term for ant-driven seed dispersal. 30-40% of understory plants in Northeastern forests are myrmecochorous.

Ant-dispersed plants produce elaiosomes— fleshy, nutrient-packed organs attached to their seeds. Ants are magnetically attracted to these lipid-dense morsels which they carry back to their colony. The seed is discarded or forgotten near the nest, giving it a chance to germinate and renew the cycle in a different location. The significance of elaiosomes ripples up the food chain: Aphaenogaster, an ant genus known for its seed dispersal, is a favored meal of the Eastern Red-backed Salamander (Plethodon cinereus).

Some of the many ant-dispersed plants at Garden in the Woods include Trillium spp., Bloodroot (Sanguinaria canadensis), Trout Lily (Erythronium spp.), Wood Poppy (Stylophorum diphyllum), Wild Ginger (Asarum canadense), and Violets (Viola spp.).

Freshwater ponds support an incredible assortment of aquatic plants and animals. Dragonflies and Damselflies (order Odonata) mate and lay their eggs in the stems of aquatic plants like Pickerelweed (Pontederia cordifolia) and White Water Lilies (Nymphaea odorata). Once hatched, the immature nymphs spend the first 1-3 years of their life underwater before metamorphosing into winged adults. Dragonflies are highly important for mosquito control and hunt them at both larval and adult stages. An increase in native aquatic plant species is tightly correlated with greater dragonfly abundance and diversity. Unfortunately, since stable aquatic ecosystems are the result of a delicate balance of nutrients, light, and species composition, aquatic habitats are regularly degraded.

Ponds and kettleholes frequently absorb runoff from surrounding areas. Lawn fertilizers and pesticides kill beneficial insects and encourage the rapid growth of algae and invasive plants. Too much algae in a pond causes dead zones by sucking the dissolved oxygen out of the water, decimating beneficial insect, amphibian, and fish populations. Removing fertilizers and pesticides from your home landscaping is a key way to preserve aquatic biodiversity in your watershed!

Most plants require some amount of sunlight, water, and basic nutrition, but many require a bit of extra assistance from soil fungi. Upper Ridge Trail is home to some notable examples of plants that rely on these fungal relationships— Blueberries (Vaccinium sp.) and Pink Lady Slipper Orchids (Cypripedium acaule). The whole Blueberry family (Ericaceae) has a special association with a fungus called ericoid mycorrhizae— the fungus provides minerals and water to the plant and receives sugar products from photosynthesis in return. This enables the plant to be more tolerant of nutrient-poor soils and droughts. Slipper orchids, like many other orchids, require fungal colonization for the seed to germinate at all. This is one reason why transplanting Cypripedium is almost impossible; they are highly reliant on the specific soil biochemistry and pH maintained by their fungal soil partners.

An abundance of soil mycorrhizae can be an indicator of ecosystem health. The presence of the Ghost Pipe (Monotropa uniflora) is one way to visualize robust mycorrhizal soils. This pale white flower may look like a fungus, but is actually a parasitic plant that no longer needs to make leaves or chlorophyll (plants’ green photosynthesizing pigment). Ghost pipes receive all of their nutrients and sugars from neighboring trees via their root mycorrhizae. See if you can spot them from June-September along the nature trails.

One of the first signs of wetland plant life in early spring is the bizarre, sculptural inflorescence of Skunk Cabbage (Symplocarpus foetidus), a title won by the pungent odor released after bruising the leaves. The red spathe housing the flower spike can even be seen poking out of a late snow, having forced its way through frozen ground using thermogenesis— the ability to create its own heat. This warm, sheltering flower produces a scent akin to rotting meat, attracting carrion flies and gnats as its primary pollinators. Spiders take up residence inside to prey on the visiting insects, and slugs, snails, and some moth larvae feed on the large leaves. As Skunk Cabbage grows, its contractile roots pull the plant deeper into the wetland soil, making them very challenging to pull or dig out. By late summer the plant withers and remains dormant until the following spring.

Lining the Calla Pool are Cinnamon Ferns (Osmundastrum cinnamomeum), named for their brown spore-producing fronds visible in spring and early summer. The ecological value of ferns is not immediately apparent— they are rarely eaten by insects and don’t produce flowers, fruits, or seeds for pollinators or wildlife. What, then, is the role of a plant like Cinnamon Fern in the landscape?

Since it thrives in moist settings, its matted roots filter water, keep wetland and stream banks from eroding, and are a perfect substrate for bog orchids to grow into. Birds collect the fuzz from the fertile fronds for nesting material, and dense colonies provide habitat for small mammals, amphibians, and reptiles. Ecosystem services like weather sheltering, hiding places from predators, mating ground, and shade for temperature regulation are just as necessary for wildlife survival— plants are much more than food!

Goldenrods (Solidago spp.) are frequently, though unjustly, maligned late season wildflowers. They are often blamed for fall pollen allergies instead of the actual culprit, ragweed (Ambrosia spp.)— Goldenrod pollen is sticky and not released into the air. Some gardeners complain about their tendency to crowd out other plants and act like weeds, but aggressiveness varies with the species in question and growing condition. With 25 species of Solidago (and more in closely related genera) found in New England, there are plenty of less intrusive options. Sweet Goldenrod (Solidago odora)—an attractively clumping, slow spreading species—has strongly anise-scented leaves that can be used for teas and flavorings.

The ecological value of Goldenrods cannot be overstated. They produce copious amounts of pollen and nectar; you can spot countless varieties of butterflies, bees, wasps, flies, and beetles visiting the flowers. Adult Monarch butterflies rely on Goldenrod nectar during their southward migration as a primary food source. The leaves of Goldenrods feed the caterpillars of dozens of butterfly and moth species. The seeds are harvested by meadow voles and birds, who also collect the abundant insects on Goldenrod colonies to feed their young. Consider growing a patch of Goldenrods somewhere in your yard— they’re resilient and low maintenance, and your local wildlife will thank you!

You might be surprised to see a cactus in a New England native plant garden, but the range of Eastern Prickly Pear (Opuntia humifusa) stretches from Florida to Ontario. It is considered endangered here, where it occurs primarily in sandy soils and dunes along Cape Cod and Nantucket coastlines. Unsurprisingly, Eastern Prickly Pears are New England’s only native cactus species. Adapting to frigid winter temperatures is no easy task! To survive the colder months, O. humifusa draws its water stores out of its pads and withers to the ground. Antifreeze-like compounds protect the remaining tissues until spring returns. The unharmed cactus sends out a plethora of large yellow flowers in June that are attractive to several types of bees and beetles. Its fruits and seeds are collected by rabbits, rodents, and birds. Both the carefully de-spined fruits and pads are edible to humans.

American beeches (Fagus grandifolia) have struggled in recent years. Beech bark disease, caused by invasive European scale insects which introduce fatal fungal infections, has greatly weakened populations from Quebec to West Virginia. A new leaf disease caused by Japanese nematodes has been exponentially spreading throughout New England after its 2012 discovery in Ohio. Researchers are still trying to understand how the nematode spreads and what actions can be taken to preserve these keystone trees—dozens of mammalian and avian species rely on beech nuts to accumulate fat for the winter.

Unfortunately, Garden in the Woods’ beeches have contracted both diseases and are being removed as the trees die. Though these losses are tragic, the dead trunks— called ‘snags’— can still support a wide array of wildlife. Look for the many small holes in the bark— these may be populated by carpenter bees, wasps, beetles, ants, or termites, which makes snags highly attractive to Pileated Woodpeckers (Dryocopus pileatus) as feeding and nesting sites. One striking stingless wasp, the Giant Black Ichneumon (Megarhyssa atrata), uses a five-inch-long ovipositor to parasitize other wood-boring larvae. Even if dead wood needs to be cut down for safety reasons, leaving it on the ground to naturally decompose over time as a “nurse log” helps restore soil nutrition and fungal networks while being a fertile place for new seedlings to take root.

The family activity area and surrounding trails are home to a variety of fungi. In addition to their symbiotic root mycorrhizal relationships, fungi are necessary to decompose dead organisms and transform nutrients into bioavailable (usable) building blocks taken up by surrounding plants— consider them the recyclers of the ecosystem. Mushrooms that grow by decomposing dead or dying material are called saprotrophic. Sometimes these saprobes can switch nutrient sources and become parasites on living trees. Terrestrial mushrooms are fleeting and may disappear a few days after emerging, while many stump and tree-based bracket or shelf fungi can last much longer. Visible mushrooms are just the reproductive structure of the often invisible mycelium, the stringy, rootlike network that lives underground, among decomposing leaves, inside logs, etc. Mushrooms are a favorite snack of chipmunks, who help with spore dispersal by stashing their feasts in hoards and burrows. Look for Turkey Tails, False Turkey Tails, and Coral Mushrooms around the family activity area.

As you walk along Hop Brook, keep an eye out for Spicebush (Lindera benzoin). This large fragrant shrub blooms early in the spring, the female plants produce lovely red berries, and the leaves turn a brilliant yellow come fall. In addition to being a lovely ornamental, spicebush is a valuable ecological host plant. Its foliage feeds the caterpillars of Spicebush Swallowtail butterflies and Promethea Silk Moths, and the berries attract more than 16 bird species. It can tolerate a wide range of lighting and moisture conditions but thrives in wet areas, making it useful for erosion mitigation. The aromatic berries, twigs, and leaves are edible and are used by Indigenous tribes for teas and spice rubs.

Near the entrance to the Lost Pond trail is a Striped Maple (Acer pensylvanicum), a smaller, shade-adapted tree. As new woodlands age, their understory first diminishes as growing trees limit sunlight to lower levels. But once a forest is sufficiently established, natural tree deaths open up pockets of light that allow for a reinvigoration of the forest floor and shrub layer. The relatively small stature of Striped Maples provides height variation in these mature forests. Having a heterogeneous habitat—a location with high species and height diversity— allows a greater number of organisms to live in a given space. Different animals prefer different food sources and nesting sites, so habitat heterogeneity ensures that there’s a bit of something for everyone! For instance, the Black-Throated Blue Warbler is an exclusive understory inhabitant that only nests and forages on short trees and shrubs. Striped Maples host 17 caterpillar species, a buffet for understory birds! Its seeds feed red squirrels and chipmunks, spring shoots are browsed by rabbits and porcupines, and winter buds are occasionally nibbled by grouse.

You may be familiar with Pachysandra (Pachysandra terminalis), an extremely common, quickly spreading plant used as a hardy groundcover all over the US. You may not know that this is a Japanese non-native that can become invasive under the right conditions. Allegheny Spurge (Pachysandra procumbens) is the native corollary to Japanese Pachysandra. It’s a shade loving, deer-, disease-, and pest-resistant, drought-tolerant plant with sweet smelling early spring flowers and mottled foliage. Though it spreads more slowly than its Japanese cousin, it fills the same horticultural niche without the danger of taking over neighboring habitats. Its normal range is the Southeastern US, though it performs perfectly well in a Northeastern garden. Filling a garden with plants native to New England should be the priority to best support wildlife and ecosystem health, but growing aesthetically similar, non-invasive alternatives to familiar landscaping staples is a good start! When shopping for plants to add to your garden, always be sure to consider the origin of the plant in question. Asking your local garden center to carry more pesticide-free natives will hopefully encourage commercial growers to meet the rising demand for ecologically friendly plants.

As you head back up the hill, make sure to stop by the Education Building patio to see the Silk Moths! We raise 2-4 species of moths each year, primarily Cecropia, Promethea, and Polyphemus moths, some of the largest on the continent. The silk cocoons on the bottom of the cages are spun by the fully-grown caterpillars during late summer in tree canopies, where they overwinter. From late May to mid July, the adult moths emerge, mate, and deposit eggs on their preferred host plants. You might have spotted the mesh bags protecting the growing caterpillars around the garden from predators. These moths will rarely cause visible damage to their host plants; their population density is low enough to escape notice.

These beautiful moths illustrate the ecological necessity of native plants— caterpillars have a specific, sometimes narrow range of plants they have evolved to digest. Due to pesticide use and habitat loss, many Lepidopterans (butterflies and moths) are in decline. While gardeners are starting to understand the importance of incorporating flowering plants attractive to bees, caterpillar host plants are frequently overlooked. Planting popular tree hosts like black cherry, maple, and hickory will increase visitation from declining moths and our native birds that rely on them for food.