Forests and Pollinators

Here in western Oregon we are gifted with many habitats and a variety of native plants for most any growing conditions. Wet soil? Try plants that love the ditches like camas, showy milkweed, or goldenrod. Shade? No problem – forests are full of shade loving shrubs and perennial plants. Gaps in the tree canopy and edges along roads or meadows are sunnier and packed with resources that increase habitat resilience and biodiversity.

Marginal land like ditches, roadsides, and rights-of-way might sound useless, but they are anything but that. Just check them and see how mosses, plants and animals take advantage of them. “Marginal” can mean not the greatest, or alongside. Land alongside roads, tracks, fields and power lines make up a tremendous amount of acreage.

Pollinators require nectar and pollen resources, but equally important is the availability of protected overwintering sites like leaf litter, large ferns, and tree cavities. Undisturbed forests, and even timber farms provide these in abundance when managed properly by leaving or adding plants that are often classed as non-timber resources. You might not be able to sell them, but they will enrich your forest in many hidden ways.

Agriculture and development daily gobble up land that was previously uncultivated or unnoticed, and that reduces refugia for native plants and animals. An example: unsprayed roadsides are one of the places milkweed can flourish unmolested to give monarch butterflies a chance to lay eggs and fuel up on nectar. Milkweeds, in fact, are some of the most prolific producers of nectar for lots of other pollinators too.

Vine maple is a favorite nectar plant for insects and hummingbirds

Oregon grape, vine maple, cascara, Nootka rose, Pacific ninebark, salal, spiraea and ocean spray are all common forest shrubs that provide superior habitat for pollinators. If your forest is lacking in diversity, you can plant these species either in the understory or along forest edges. If you have open spaces, you may even want to consider planting “pollinator patches” of native flowers, such as lupine, meadowfoam, clarkia, selfheal, goldenrod and aster. Many of our common forest plants, and indeed our food supply, may depend on this kind of proactive conservation work!

Kirk Hanson, Forestry Director
Northwest Natural Resource Group

One advantage to growing forest-adapted shrubs, wildflowers and trees is early season nectar. The ethereal white flowers of Osoberry (Oemleria cerasiformis) appear against the green forest background as early as January. Tall Oregon grape (Mahonia aquifolium) may accompany red flowering currant (Ribes sanguineum) to dramatic effect. The dense creamy sprays of goatsbeard (Aruncus dioicus) on shady edges attract multiple species of native bees.

Late season nectar is often scarce because our hot, dry summers force most plants to get their reproducing done early. Summer dormancy is a survival strategy that produces yellow leaves on perfectly normal osoberry late in the season. However, goldenrod (Solidago spp. and Euthamia occidentalis), Aster spp, and rabbitbrush (Ericameria sp.) are used extensively by insects late in the season. With a little moisture, some perennials will even bloom a second time.

Pollinators aren’t the only beneficiaries of wise planting. Birds, mammals, and predators all use the fruits, structures, and protection that a diverse forest provides. Lower levels of pests and higher soil moisture and fertility are a few of the by-products for landowners and farmers.

Of course an equally powerful way to protect wildlife and pollinators is to reduce or eliminate agricultural chemicals on your property. Properly using those you need, in small quantities, and with great care with respect to timing of application is essential. If you live in Yamhill County, join the Yamhill Butterfly Gardeners, the Native Plant Society, or get in touch with Taylor Gardens for a consult to explore your options.

Serviceberry (Amelanchier alnifolia)
Tall Or grape + red flowering currant
Iris tenax
Can you see the flowers on the salmonberry? (Rubus spectabilis)
old growth Evergreen huckleberry (Vaccinium ovatum) with a ground cover of Maianthemum racemosum
Bleeding heart (Dicentra formosa)
Many native pollinators use western goldenrod, often at the same time
-Photo: Sonya Wilkerson
Good old showy milkweed (Asclepias speciosa) is making a comeback for feeding monarch butterflies
Goatsbeard (Aruncus dioicus)

Everybody Needs A Hedgerow

We can all appreciate the fact that bats and birds eat a lot of insects. They control populations of pests that would otherwise destroy a lot of vegetation.

That is one example of an ecosystem “service”. Clean water, clean air, pest control, are provided by complex food webs, involving untold numbers of producers (e.g. plants, nitrogen-fixing bacteria) and consumers (insects, fungi, microbes, mammals, etc).

Now think about what happens if something goes wrong: species die, we add more carbon than our decimated forests and grasslands can absorb. Gradually we lose services that we need to live. The system breaks down, and no longer supports our health and safety.

Habitat is the key to survival for plants and animals. Wilderness and managed reserves are the highest quality habitat, but the space in between – the “matrix” (no, not the movie one – the real one) that we humans take up with cities, towns and rural agricultural land is so vast, and stretches across so many boundaries, that it becomes essential to manage it properly to ensure the integrity of the safety net that keeps us alive.

This was the topic of a recent article in the New York Times about a research paper that documents the toll of habitat loss in the matrix:

Every fall the calliope hummingbird, which weighs about as much as a penny, braves high winds and bad weather to migrate from Canada and the northern United States to as far south as Mexico, then back again in the spring — a total of 4,000 to 5,000 miles.

The journey is one of several dozen “spectacular migrations” — in the air and on land — that are chronicled in a new report by the Wildlife Conservation Society…But the report warns that these migrations are in peril.

As migration routes are disrupted, other species can be affected too — including humans. Take the case of migratory songbirds, whose numbers are down across North America.

In the spring, these birds eat 3,000 to 10,000 tons of insects each day as they travel. “It’s a legitimate concern,” said Dr. Wilcove, of Princeton. “Presumably with the decline of songbirds, insect damage to crops and forests could be worse.

New York Times December 19, 2011

That last sentence is a profound understatement. Unfortunately, this is not news. The great conservationist, Aldo Leopold began writing about it over 80 years ago. In one of the essays published after his death he addresses the issue in a nutshell:

The shrinkage in the flora is due to a combination of clean-farming, woodlot grazing, and good roads. Each of these necessary changes of course requires a larger reduction in the acreage available for wild plants, but none of them requires, or benefits by, the erasure of species from whole farms, townships, or counties. There are idle spots on every farm, and every highway is bordered by an idle strip as long as it is; keep cow, plow, and mower out of these idle spots, and the full native flora, plus dozens of interesting stowaways from foreign parts, could be part of the normal environment of every citizen.

Leopold, Aldo 1948

A Sand County Almanac: And Sketches Here and There

As much as we’d like to have unspoiled wilderness to shelter all sorts of creatures, the time is long past when there is going to be enough, or enough in the right places, for many species. We have to take care of the matrix lands – the places where we live.

Nature is not “out there” it’s here where we live.

What’s needed? Well, the best case is that there will be some connected places that afford the essentials for wildlife:

  • food
  • water
  • shelter and resting places
  • places for homes

Here’s how Leopold explained why we have to conserve habitat patches within farmland:

A city consisting of endless restaurants and dining rooms, with no bedrooms or living-rooms nearby, would support about as many people as Iowa supports upland game birds. Birds cannot rest, breed, or dodge their enemies in one continuous soup-kitchen…Iowa’s problem is to induce the farmer to let some grass and brush grow.

Report of the Iowa Game Survey, Chapter One: The Fall of the Iowa Game Range (1932)

We all need hedgerows

Hedgerows are ideal habitat to give insects, birds, and other beneficial wildlife places to find food and shelter. They will create balance in the landscape and give you a chance to enjoy the diversity of life on earth. The great thing about hedgerows is, it is something we can all do to make a difference. If you link yours with your neighbor’s you have an even larger habitat that is more than the sum of its parts. And hedgerows can be any size – even a few shrubs will improve things.

• Hedgerows can be groomed or left to grow on their own.

• The best ones contain a diversity of plants native to your local area, of varying heights, and with different bloom times.

• Evergreens are exceptionally useful to wildlife and help prevent erosion and excess runoff year-round.

© Copyright Eileen Henderson and licensed for reuse under this Creative Commons License

• By choosing the right plants for the space, you will not need to “control” the growth of your hedgerow unless you want to. This one is wild – yours does not have to be.

Bare root plants and plugs from the Conservation District are small but inexpensive

I started a hedgerow along the access road from Gopher Valley Road this year. I’m looking forward to watching the plants grow and produce wildlife galore.

If you’d like help with planning, planting, grooming or pruning your hedgerow, I’d be happy to help you through my business, Taylor Gardens