Winter is upon us and, like many others, we here at the Land Trust have been overjoyed to see rain falling on our parched landscape!
In many areas, the onset of winter initiates a silent and still time on the land when plants and animals slow down, become inactive, or migrate to warmer areas.
In stark contrast, the arrival of winter in Napa County’s wildlands signals the end of the long, hot, dry season and a time to revive, grow and reproduce. Flowering plants, fruiting fungi, traveling amphibians, hydrating mosses and lichens, and overwintering birds all contribute to the flurry of activity that characterizes winter in Napa.
Beginning in November, manzanita (genus Arctostaphylos), a prominent component of chaparral habitats across the Land Trust’s preserve system, produce profusions of bell-shaped, pink and white flowers. Nectar and pollen produced by these flowers help to sustain hummingbirds, butterflies, moths, ants and native bees through the winter months.
Hovering Anna’s hummingbirds, with their brilliant green backs and scarlet throats, can be seen inserting their bills into the tiny opening of each flower with near-perfect precision. In licking the nectar off the inner petals of each flower, these hummingbirds also inadvertently pick up pollen grains left behind by bees. They then transfer this pollen to the stigma of the next flower visited, performing an important pollination service.
Toyon (Heteromeles arbutifolia) berries, which begin forming in midsummer, finally ripen around December, adorning native woodland and shrub habitats with patches of fiery red. These brightly colored, fleshy fruits provide an important winter food source for a host of overwintering and resident bird species including varied thrush, ruby-crowned kinglet, cedar waxwing, California thrasher, oak titmouse and northern flicker.
In addition to the many birds that rely on toyon berries, so do several mammals, including black bears, foxes and coyotes. In consuming the fruits, these animals then help disperse the toyon’s seeds, creating a mutually beneficial plant-animal relationship.
After long periods of dry-season dormancy, lichens and mosses come alive within minutes of winter rains. Hundreds of species of water-invigorated lichens and mosses create a flush of brilliant greens, oranges and yellows on tree trunks, boulders and even fence posts.
Lichens (actually symbiotic partnerships between two organisms, a fungus and an algae or cyanobacteria) lack roots and the ability to retain or circulate water. Amazingly, they are able to lose up to 98 percent of their water content and survive. Mosses, too, are able to weather long, hot, dry periods and extreme desiccation. This means that, when the winter rains come, lichens and mosses have to kick it into high gear, absorbing water, growing and reproducing while conditions are right.
As winter storms arrive, an impressive array of mushrooms emerge from rain-soaked soil and leaf litter below the canopy of oaks, redwoods, Douglas firs and other woodland species. In addition to being the objects of naturalist and culinary interest, mushrooms play an important ecological role.
Fungi are critically important in the decomposition process, breaking down organic matter and returning valuable nutrients to the soil. Mushroom species known as mycorrhizal fungi form mutually beneficial associations with the roots of native plants, enhancing the plant’s ability to acquire minerals and nutrients from the soil while utilizing the plant’s sugars for growth and reproduction.
Beginning in the fall, Napa County’s already-impressive suite of resident bird species is augmented by an influx of migratory, overwintering species. Arriving from breeding areas in the north and at higher elevations, these migrants rely heavily on intact native habitats within Land Trust preserves and other conservation lands to survive the winter in this temperate climate zone.
Our local Christmas Bird Count, one of hundreds that take place across North America each winter, reliably turns up over 130 species. Whether catching a glimpse of a sharp-shinned hawk as it flies silently through woodland understory on the hunt for songbirds, or gazing at the stunning plumage of cedar waxwings as they feast on toyon and Pacific madrone fruits, winter is a great time to get out and enjoy avian wildlife.
When winter rains return, coast range newts (Taricha tarosa tarosa) can be regularly encountered on the move in Napa’s natural areas. With their deep red backs and bright orange bellies, these traveling salamanders are en route from upland estivation (desiccation prevention) sites to breeding areas in streams and wetlands. No more than 4 inches long, their journey of up to 2 miles can take weeks.
Coast range newts exhibit incredible navigation skills on their trek, using stars and the Earth’s magnetic field to find their way back to the same natal breeding site year after year. These amphibians are protected from predators along the way by a highly potent neurotoxin emitted through skin glands.
To experience these blooming, fruiting, flying, growing and navigating natural wonders on the Land Trust’s preserves, consider joining us for an upcoming field trip, visitor orientation or stewardship workday. For information visit www.napalandtrust.org, or email us at email@example.com.
Mike Palladini is land stewardship manager for Land Trust of Napa County.