The Nature Conservancy (TNC) sponsored a volunteer day at Moxee Bog on 13 October and boy howdy did we get a lot done! It’s astonishing what 10 motivated and strong volunteers can do. We cut back vegetation, cleared a path along most of the western fence line to provide better access to the property, cleared brush along the southern fence line, and cut back tules in the immediate area where violets were found earlier this year.

The property is south of Yakima, just northeast of the gap where the Yakima River, railroad and I-82 have cut through the basaltic fold of Rattlesnake Ridge. It’s also not far from the landslide discovered a year ago that continues to be monitored using multiple instruments. The Moxee Bog property is an 8-acre parcel that was acquired by TNC in 1966 after the butterfly Boloria selene, also known as Silver-bordered Fritillary, was found in abundance on the property.

Although B. selene is not endangered in Washington state, it is found in small populations in only a few isolated locations. When the glaciers receded at the end of the Ice Age, the butterfly habitat became restricted to a few specific wet locations. Moxee Bog is special because it is a small wetland area in the midst of sage-steppe habitat where natural rainfall averages only 9 inches per year.

Once TNC had full ownership of the former pasture land, they fenced out the neighboring cattle, thinking to help preserve the host plant, Viola nephrophylla, or northern bog violet. Additionally, the hydrology of the area has changed as a result of regional water management changes. Re- grettably, these changes have proven to be the demise of the butterfly, and very nearly of the violet. Cattails, tules, rushes, and willows have grown up and shaded the understory so heavily that the few remaining violets are struggling.

A partnership of TNC and the Yakima Native Plant Society located a handful of remaining violet plants this spring at the base of dense tules in a damp area of the bog. Dr. David James led a WBA field trip over the summer to see the violets on the property and to look for violets on a nearby property owned by the Bureau of Reclamation. Over the summer ~550 acres were assessed for likely habitat on the BoR land, and promising areas searched intensively. Especial thanks go to Cathy Reed and Ed Lisowski from YNPS who participated in mul- tiple searches both at Moxee Bog and at the BoR lands. This search indicated that Moxee Bog and an adjacent private property are the only known sites of natural violet populations in the area.

The goal of the TNC volunteer day was to prevent further decline of the violet habitat as TNC examines the possibility of a potential restoration effort. TNC has hired a wetland restoration expert to identify outline courses of action that might be undertaken to restore the habitat to a condition which may once again be hospitable for the violet. That report will be provided to TNC later this year.

While waiting for this report TNC steward Nicholas Altadonna decided to organize an effort to give the remaining violets the best chance possible for the short run. We targeted a region of approximately 3300 square feet comprising the recent violet finds as well as regions where violets have historically been found. This encompassed a very wet area of dead tules growing through a mat of vegetation to the north and a dryer meadow area further south where violets were found in 2014 by Dr. David James and his colleague. The goal was to cut all vegetation to ~ 20″ height, providing sun for any sheltering violets, but also shading them from the blazing heat next summer. The vegetation in the targeted area is patchy and the newly cut areas provide a range of habitats, some of which may foster violet growth and regeneration.

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