The Botanists at Crater Lake National Park by Elizabeth L. Horn

Research Natural Areas (RNAs) are designated to represent significant, undisturbed ecosystems, where natural processes can take place unhindered. These sites are valuable for scientific research and as a reservoir of native plants and animals. These sites are designated administratively by state or federal agencies and do not require congressional action. They are chosen to represent specific “cells” described in a statewide natural heritage plan. Four such areas have been designated in Crater Lake National Park (Mark 2000). The state’s Natural Heritage Plan can be found at http://oregonstate.edu/ornhic/publications.html.

The Pumice Desert RNA consists of 3,055 acres along the North Entrance road northwest of the Crater Lake rim. It represents a barren pumice and ash desert surrounded by lodgepole pine forests. Ecological succession and slowly encroaching lodgepole pine are being studied and monitored (Horn 2002).

The Desert Creek RNA includes 1,869 acres in a remote northeast portion of the park. It includes a remnant plant community of bitterbrush (Purshia tridentata) and old growth ponderosa pine. Outside the Park similar communities have been logged or grazed.

The Llao Rock RNA consists of 435 acres of thick pumice deposits and represents subalpine timberline typical of southern Cascade pumice fields. Two rare plants can also be found there: the Crater Lake rock cress (Arabis suffrutescens var. horizontalis) and the pumice grapefern (Botrychium pumicola). Llao Rock also contains a whitebark pine plot that is part of a larger program within the park to monitor whitebark pine communities.

Sphagnum Bog RNA along the Park’s western border includes 180 acres with plants that contrast sharply with the surrounding pumice dominated forest. The insectivorous sundews (Drosera anglica and D. rotundifolia) grow here as well as the rare Mazama collomia (Collomia mazama). Sphagnum Bog contains a diversity of plant communities that makes it an outstanding example of a Cascade bog or mire.