New Search
EMERALD CHAPTER - NPSO MAY 1995 <br /> Methodology <br /> _. <br /> Project Design. The goals of the project were to: 1) sample flowering plants at a sufficient <br /> level to provide a reasonable estimate of population size, and 2) map the outer boundary of <br /> the population. A statistician supplied options regarding various levels of precision and <br /> confidence which could be used to achieve the first goal. <br /> Original project design included more complete demographic sampling which would have <br /> provided data for future analysis of reproductive trends. Because of the surprisingly high <br /> number of plants encountered when field work commenced, this portion of the sampling had <br /> to be dropped so as to be able to complete the project within budget limits. Demographic <br /> sampling undertaken in future surveys could provide data for trend analysis. <br /> Timing. Field setup and data collection occurred in late March through early April 1995, <br /> during the period of peak flowering when plants were most visible. Future sampling may <br /> need to occur slightly earlier or later to accommodate peak flowering time, which may vary <br /> depending on weather conditions and soil temperature. <br /> Personnel. Field work was conducted by John Koenig and Ethen Perkins (consultants) under <br /> a contract with the City of Eugene. Ed Alverson (City of Eugene and The Nature <br /> Conservancy), provided direction on field counting technique and other aspects of <br /> methodology. Manuela Huso provided statistical design and calculations, with input from Ed <br /> Alverson. Bruce Newhouse (NPSO) served as project coordinator. <br /> Field Data Collection. Two permanent baselines were established in the study area: one in <br /> the south portion, and one in the north portion (see Attachment B). The south baseline <br /> begins near the southeast corner of the community gardens and runs directly east just north <br /> of the treeline for 145 meters. The north baseline aligns with the center line stripe of 27th <br /> Street (to the west), beginning at the curb and running east for 155 meters. <br /> Ten meter intervals on the south baseline, and twenty meter intervals on the north baseline <br /> were permanently marked with pieces of rebar (each 1/2" diameter by 18" long) so as to <br /> allow for precise relocation in the future. The head of each rebar is ensheathed in yellow <br /> plastic tubing for 1 to 2 inches to facilitate visual relocation. Aluminum tags with transect <br /> identifications are wired to the head of each rebar for the same purpose. The rebar was <br /> pounded into the ground at the end of the project, with only 1" or less left above ground. <br /> On the south baseline, 93 randomly- located 1/2 meter wide transects were located <br /> perpendicular to, and running north from the baseline (see Attachment C for distances from <br /> the beginning of the baseline to the head of each transect). Along the longer north baseline, <br /> 105 such transects were sited. The transects vary in length to accommodate the irregularly - <br /> shaped survey area. All flowering plants were counted within each transect (Attachment C). <br /> Lomatium plants are difficult to count because some plants which appear to be separate <br /> actually originate from a common taproot. The field crew counted flowering stems growing <br /> 2 cm (a finger width) or closer as one plant, and stems growing farther apart as separate <br /> plants. Plants were counted in three categories: plants with one flowering stem, two <br /> flowering stems, or three or more flowering stems. <br /> SURVEY OF LOMAT7UM BRADSHAW!! AT AMAZON PARK P. 2 <br />