Graber (1980) found that heavy foot traffic on the Appalachian 

 Trail represented a major threat to the survival of Robbins 

 cinquefoil. An unknowing hiker may step on and crush a plant, but 

 more important, in the long term, is the shifting and dislodging of 

 the stony surface layer, which occurs when hikers trespass on the 

 cinquefoil habitat. The abrasion and churning caused by hikers' 

 footsteps can eliminate the protected spaces between the individual 

 stones, which often hold fine soil and organic matter. These minute 

 sheltered spots are the nurseries for newly germinated Robbins 

 cinquefoil, and it is here that they grow and survive. When the stony 

 surface is disturbed by hikers, the soil between the stones loosens 

 and is soon blown or washed away in severe mountain storms. Once 

 this bit of soil is lost, there is little chance of nurturing a seedling. 

 The trail-side zone disturbed by the hikers has widened in recent 

 decades. The cinquefoil has died out completely on one side of the 

 trail and is largely absent on habitat within 26 feet of the trail on the 

 other side. 



As a first step in reducing the human impact on the Robbins 

 cinquefoil, we observed the hiker population to determine their 

 numbers, characteristics, time of travel, and motives. 



METHODS 



Hiker activity was observed during the summer of 1980. A 

 student assistant, who was out of sight, noted time, group size, 

 direction of travel, hiker pack size, age, and especially hiker 

 behavior on and adjacent to the cinquefoil colony. When hikers left 

 the trail and walked on the Robbins cinquefoil habitat (trespassed), 

 the observer determined the purpose of the visit by watching what 

 the individual did. 



To supplement these observations, three electronic pressure 

 plate counters were placed in the trail. The counters were carefully 

 calibrated initially and checked for accuracy frequently during the 

 summer. They provided a total count of all foot traffic on the 

 Appalachian Trail during the study period. The chi-square test of 

 independence was used to evaluate the hourly, pack-class, direc- 

 tional, and age-class data. 



RESULTS 



From 15 June to 31 August, we made counts during parts of 40 

 days and observed 1,936 hikers. Of those observed, 194 hikers 

 (10.02%) walked past the posted signs and trespassed on the Robbins 

 cinquefoil habitat. 



