2020 NPSO Annual Meeting Cancelled

Due to the COVID-19 pandemic, and in the best interests for the health and safety of our members, the Cheahmill Chapter has decided to cancel the Annual Meeting this year. While the number of new cases should decline over the next several weeks and months, subsequent waves of COVID-19 are likely to recur once social distancing is relaxed. We are exploring hosting the meeting next year (2021) at Spirit Mountain Lodge and offering much the same program.

If you have already sent in your registration form and payment, your checks will be shredded. Those whose checks were already deposited will receive a refund.

We look forward to seeing all of you in 2021, hopefully at Spirit Mountain. Please stay safe and healthy through this difficult time.

NPSO 2020 Annual Meeting

May 29 - 31     Spirit Mountain Lodge, Grand Ronde, Oregon

Field Trips

Saturday May 30, 2020    9 a.m. - 4 p.m.                    Field Trip # 23

Deer Creek Prairie Park and Yamhill Oaks Preserve


Kincaid's Lupine (Lupinus organus)


Difficulty:     Easy to moderate  (0.5 mile at Deer Creek Park; 1.5 miles at Yamhill Oaks Preserve) - Easy walk at Deer Creek Park. At Yamhill Oaks Preserve, moderate off-trail walk with minor elevation gain, uneven ground, and depressions hidden by grass.

Elevation:     Negligible

Group Size Limit:     20


Yamhill Oaks


Trip Description:     For both hikes, a special feature will be a butterfly tour and talk by lepidopterist Dr. Paul Hammond.

The 30-acre Deer Creek Prairie Park is Yamhill County's most biologically diverse park, with upland and wet prairies, beaver ponds, and riparian habitats. Learn about its unique history and its gradual recovery and restoration. It has the largest stand of tufted hairgrass (Deschampsia cespitosa) in the northern Willamette Valley and is a designated mitigation site for enhancement of the endangered Fender's blue butterfly and its host species, the threatened Kincaid's lupine (Lupinus oreganus). Other notable prairie plants include fernleaf biscuitroot (Lomatium dissectum), common camas (Camassia quamash), mariposa lily (Calochortus tolmiei), red columbine (Aquilegia canadensis), Oregon sunshine (Eriophyllum lanatum), narrow-leaved mule's ear (Wyethia augustifolia) and Nelson's checkermallow (Sidalcea nelsoniana).

After lunch beneath Deer Creek Park's grove of 100-year old Oregon ash, we will tour the Yamhill Oaks Preserve. This former ranchland is managed by the Yamhill Soil & Water Conservation District and is not generally open to the public.

The preserve is a 313-acre remnant of upland prairie and oak woodland with over 27 at-risk species that depend on habitats found at the preserve. It hosts a large population of Fender's blue butterfly and Kincaid's lupine (Lupinus oreganus), Oregon iris (Iris tenax), rose checkermallow (Sidalcea malviflora), and narrow-leaf onion (Allium amplectens). A Douglas-fir plantation is being converted to native upland prairie with slender cinquefoil (Potentilla gracilis), cat's ear (Calochortus tolmiei), golden paintbrush (Castilleja levisecta), blue-eyed grass (Sisyrinchium bellum), yarrow (Achillea millefolium), bare-stem desert parsley (Lomatium nudicaule), and bastard toadflax (Comandra umbellata) present. Deer Creek meanders through the property, and a variety of native trees and shrubs grow within the riparian zone. Undeveloped wet prairie with many native rushes and sedges border the creek. Since there is no official plant list for the site, participants are requested to help generate a list for future visitors.

Appropriate Clothing and Footwear:     Waterproof footwear and hiking poles advisable.

Special Considerations:     Restroom and picnic tables at Deer Creek Prairie Park. Poison oak present.


Meeting Place and Time:     Trip # 23 leaves at 9 a.m. from Spirit Mountain Lodge entrance. Plan to arrive 30 minutes before departure time to meet your group and arrange carpools.

Driving Miles and Time from Spirit Mountain Lodge:     18 miles, 23 minutes to Deer Creek Prairie Park, plus 0.5 mile from Park to Yamhill Oaks. Mostly paved roads; short driveways are gravel.

Driving Directions:     Trip leaders will provide detailed driving instructions.


Leaders:       Dave Hanson, Josh Togstad, Paul Hammond

For Deer Creek - Dave Hanson,steward of Deer Creek Prairie Park for more than 30 years, member of Yamhill County Parks Board, Cheahmill Chapter. Paul Hammond, Oregon State University lepidopterist, and the foremost authority on the Fender's blue butterfly.

For Yamhill Oaks - Josh Togstad, riparian specialist and stewardship technician, Yamhill Soil & Water Conservation District. Paul Hammond, Oregon State University lepidopterist.



Plant Lists and Other Information:    

(For Deer Creek species lists by scientific name and common name, see Field Trip #4.)



Common Camas (Camassia quamash) thrives in wet areas of the park.



A boardwalk eases the walking over wetlands at Deer Creek Prairie Park.



Tolmie's cat's ear (Calochortus tolmiei)


Photo: Amie Loop-Frison
A Fender's Blue Butterfly on Kincaid's Lupine (Lupinus oreganus)