Native bee habitat at TESC organic farm

Notated Google Maps image of The Evergreen State College Organic Farm

Completed form

I used a guide titled Native Bee Conservation Pollinator Habitat Assessment Form and Guide: Farms and Agricultural Landscapes from The Xerces Society to guide my studies of Pacific Northwest native bees and their habitat needs. I completed the form as if I was a decision-maker at the farm looking to improve it for native bee habitat specifically.

Additional notes

Section 1: Landscape features

The landscape within a 1/2 mile is mostly forest and residential buildings with some ornamental gardens. There is little open area. Evergreen trees dominate most of the forest; Western Red Cedar (Thuja plicata), Western Hemlock (Tsuga heterophylla) and Douglas Fir (Pseudotsuga menziesii). It is also rich with Bigleaf Maple (Acer macrophyllum), Red Alder (Alnus rubra) and occasionally other deciduous flowering trees like other maples, madrone, and dogwood. The understory is dominated by ferns as well as native flowering shrubs; mainly Red and Black Huckleberry (Vaccinium parvifolium and ovatum), Salmonberry (Rubus spectabilis), Salal (Gaultheria shallon), and Osoberry (Oemleria cerasiformis). You can also find Oregon Grape, Thimbleberry and native roses Nootka and Baldhip, among others. Near the campus there are large patches of noxious English Ivy (Hedera helix).

Summary: this area is mostly wooded. However, floral resources seem to be abundant in clearings and roadsides where shrubs and annual wildflowers get ample sunlight, as well as on Maple trees. Nesting habitat is plentiful but not always close to forage.

Section 2: farmscape features

When I first evaluated how much of the farm is natural or semi-natural habitat, I considered the farm to encompass Demeter’s and the community gardens. I now consider those to be irrelevant because they’re not being tended by the Practice of Organic Farming program, nor do they really qualify as “farm” operations. Given that, the percent of farm that is undisturbed is more than 10%. That 10% encompasses the various strips and “beetle banks” left purposely wild as beneficial insect habitat. These areas include quality woody nesting material and floral resources for native bees.

Other relevant features include a recently planted, very diverse perennial native shrub strip on the road side of the farm, bordering forest, blooming cover crops, and unmowed strips between crop rows.

Section 3: foraging habitat

This section specified the relevance of home gardens, so I included Demeter’s, the Herb Garden, and the Community Gardens. Non-invasive flowering plants make up about 40% of the non-crop area of the farm.

Nootka Rose, Salmonberry, Elderberry, and and Red and Yellow Currant, Osoberry, and Thimbleberry are all good forage shrubs for native bees. These are abundant in the insectary habitat zones. There is also very diverse and abundant floral resources in the community garden, although there is also a lot of invasive plants such as comfrey, Pentaglottis, Kale, and Buttercup which are competing with native wildflowers. Demeter’s garden has been completely overcome by Comfrey but still harbors an apple tree and some perennial shrubs including Vaccinium ovatum. I counted 16 species of spring-blooming non-invasive species within the farm (close to crops).

Cover crops are allowed to bloom in the summer, including Buckwheat, Vetch, and Clover.

Next steps: Count summer- and fall-blooming non-invasive species, to get a sense of what is present and which seasons may be lacking in nutritious resources for native bees.

Section 4: native bee nesting habitat

Ground nesting opportunities

This is a great farm for ground-nesting bees, because POF keeps tilling to a minimum. There is also a few areas on the western half (where soil drainage is good) which are mulched and not tilled for years, creating stable ground-nesting opportunities. This includes the lavender rows and the road-side native shrubs strip. The grassy pasture, when not grazed (which is most of the time), provides protection for ground-nesting bees who make shallow holes.

Photo credit to Steve Scheuerell

Wood nesting opportunities

Nootka Rose, Salmonberry, Elderberry, and and Red and Yellow Currant are hollow and/or pithy plants found on the farm. There are also artificial houses with stacked tubes that are old, but seem to be in use currently by some kind of insects, if not bees.

Surrounding the farm and not far from on-site flowering plants, in the woods is ample pithy shrubs, woody brush, logs, stumps, and snags.

Photo credit to Steve Scheuerell

Section 5: farm management practices

Pest management

They use organic insecticides, but this is kept to a minimum via other pest control methods. This entails using crop rotation, cover cropping, high diversity, resistant crop varieties, intercropping, sanitation, and other non-chemical interventions. Frequent mowing of potentially animal-pollinated pasture plants minimizes the impact of insecticides on pollinators.

Land management

Mowing is not limited, but there are distinct areas left undisturbed (shrubs and trees). Livestock grazing is occasional and limited to late summer after the peak floral season. The orchards are not mowed as intensively. Flowering plants are used in cover- and inter-cropping.

Recommended further action

  • In the fall or winter, remove bee cocoons and cells from all the mason bee houses on the farm, and clean or replace the tubes and holes. Cocoons should be stored in a fridge over winter and released when temperatures reach 55f. Releasing them means placing them outside in a sheltered place (the yellow wooden bee house near the herb garden).
  • Record the number of species of native wildflowers in summer and fall to determine if late-season pollinators have diverse resources available.

Contact me with questions!

Corinne

steemm07@evergreen.edu

e.corinne.s@gmail.com