Activity 10: Field Navigation Using Orienteering Methods

Introduction

The activity this week made use of navigation maps the class made earlier in the year in Activity 3 The maps were used to navigate a course set out by Dr. Hupy at the University Wisconsin Eau Claire Priory. 5 points through out the wooded area of the property were found by using orienteering techniques which were learned when we constructed our navigation maps about a month and a half ago. Each group was assigned a different order of the 5 points so group wouldn't just follow each other around.

We were split up into groups of three which is the ideal number when doing orienteering exercises. Each person in the group has a different task which included the bearing finder holding the compass, a pace counter and a runner. Before heading into the woods we were given the UTM and lat/long positions of each point which we then placed on our navigation maps. All the groups started from the same location and took pictures of each stop to prove they had been there. The points were marked with pink tape around birch trees. 

Study Area 

The Priory (Figures 1,2) is a large piece of property owned by UW-Eau Claire about ten minutes away from the main campus and 3 miles south of Eau Claire. At the current time it is serving as a children s daycare center and dormitories for UWEC students. The majority of the property is heavily wooded and rather hilly which made navigation rather difficult. There is lots of buck thorn and brambles as well as downed trees and other obstacles to navigate around. While navigating between points we tripped and stumbled on logs and stumps and slid down steep embankments which made collecting an accurate pace count difficult. Although the terrain is somewhat challenging the other field conditions were perfect. It was a sunny spring day with hardly any clouds and a air temperature in the mid 70s. There was a slight breeze which kept us cool while trudging through the woods and the navigation area was dry with no mud to slip on. We heard horror stories of past years when this activity was done with snow on the ground so I am thankful that was not the case for our activity. The nice weather made this activity easier and more enjoyable.

Figure 2 This sign at the Priory entrance.

Figure 1 is a view of the front of the main
building on the Priory property where the child's
daycare and college  dormitories are located.

Methods

Upon arrival at the Priory Dr. Hupy gave each group of three people as set of 5 coordinates,each set being in a different order. Each group was then told to plot these points on the previously created navigation maps. The groups used UTM grids and meter increments given them to plot the points (Figures 3, 4). Our group right away recognized that the scale on the UTM grid was incorrect. The scale was too large and did not include enough decimal points to differentiate between each grid line. This significantly decreased the plotting locations accuracy which made the navigation to each point more difficult as well. We knew general ballpark of the points but we were off by roughly 10 to 15 meters on each point. Thankfully the trees did not have leaves on them and the pink tape stood out and was easy to see.

     

Figure 3 This is the 5 points we were given to plot. Text boxes and the bad scale on our map made it difficult to accurately plot the points, which did create problems for us later on in the exercise.  

Figure 4 is a map showing the Priory property. The red box is  where the navigation exercise was supposed to take place but as you can see the course ended up being slightly outside that area.

After each group had the points plotted Zach Hilgendorf, a classmate with knowledge on orienteering went over the a review of materials and basic procedure we had read about previous to coming in the field. He did a demonstration of how to properly use distance-bearing navigation to navigate from one point to the next.The first thing to do is assign each group member a job. Again the three roles are the bearing locator, pace counter and runner. In order to find a bearing you use a compass(Figure 5). You align the edge with the point where you are currently located and the next location. The direction of travel arrow on the compass always needs to be pointed at the point you want to go to next. Then spinning the dial on the compass and pointing it to true north on the map the bearing line will show you the direction of travel (Figure 6,7). Then remove the compass from the map and line the red north arrow up with the red arrow outline in the bezel of the compass. This is referred to as putting red in the shed. As long as you keep the red in the shed the direction of travel arrow will always point you to your next location failure to do so will lead to incorrect navigation headings and a lot of wasted time.

Figure 5 is an orienteering compass similar to the ones we used for this exercise. You can see all the different parts labeled above. Knowing how to use this device properly is the key to this exercise. 

Figure 6 shows a student setting
up the bearing on the compass. Setting north
 on the compass to true north on the map 
to get the bearing direction.

Figure 7 is Dr. Hupy giving instructions
on how to plot points to the groups of 3 and
giving final instructions before we headed into 
the woods.

Next the runner the is sent out to a set landmark or recognizable point in the exact bearing of the next location. Once the runner reaches this point the pace counter walks in a straight line to the runner recording how many paces he/she takes to get a rough estimate of distance traveled. Comparing this pace count to measured lengths on the map tells you approximately how far it is between the points. This process is repeated for each location.

Once this demonstration was over we were given the OK to start navigating to the first point. We started at a light pole just off of the parking lot (Figure 8) and set our bearing based on our map towards the first point. The runner was sent to the edge of the woods to a large tree in the bearing direction followed by the pace counter recording the distance. This was repeated again and in a short time the first point (Figure 9) was found on the edge of an open area. The location of this point was very visible so navigation right to the point was not necessary because it could be seen from a ways away. This navigation only took 5 minutes or so.

Figure 8 is the light pole from which each group
 began  their navigation to the other 5 points.

Figure 9 is a picture of point 1 proving that
we were there.

The next point was more difficult and the error of locations on our navigation map came into play. We followed the bearing and estimated the distance but overshot the point. We actually ended up finding point number three instead (Figure 10) about 20 minutes later. We then back tracked from point 3 to 2 which were fairly close together. We had missed point two the first time by a good 20 meters again because of the bad scale on our map. Point 3 to 2 (Figure 11) took about 10 minutes to navigate.

Figure 10 is a picture of point 3 proving that 
we were there.

Figure 11 is a picture of point 2 proving that 
we were there.

We then navigated from 2 to 4. Point 4 (Figure 12) was pretty easy to find. We had a good bearing and had a pretty accurate idea of distance but simply went too far. It was hidden over the side of a bank which we walked right past and failed to look down the embankment.  We only had to backtrack about 4 meters to find the point so we were very close with our calculations. Had we not overshot the point it wouldn't have taken as long to find but it took about 15 minutes because of that mistake.

Figure 12 is a picture of point 4 proving that we were there.

The final point (Figure 13) was rather difficult. Our bearing for this point was not spot on again caused by the map scale and this sent us into some very thick brush where our pace count got very skewed. For most of the navigation we figured that 85 paces would be close to 100 meters in distance but in this area it was more like 100 paces equaled 100 meter because of the small steps through thick brush. For this point we got our bearing and then split up and moved in a line in that bearing direction. This helped us to covered a wider area and increase our chances of finding the final point. This strategy worked. I crested a hill and down on the other side was the final point. The bad bearing and thick brush made this the longest navigation of about 25 minutes.

Figure 13 is a picture of point 5 proving that we were there.

Discussion

This excise had components that worked well and others that did not. It was quite difficult to use this technique in the heavily wooded and brush areas of the Priory. I did not expect it to be that difficult but all those obstacles really add up. It was hard for the runner to find a good distinguished position in line with the bearing because of all the brush and branches in the way. The pace count is what was effected the most by the terrain and study area features. Some places you could walk easily using the 65 paces per 100 meter measure but other places struggling through brush is almost 100 paces for 100 meters. Changes in elevation also greatly effected the accuracy of the pace count. Our map scale also made this exercise more difficult than it had to be. If we had had a better map scale we would have been more spot on with our bearings, cutting down on the time it took to find the points.

Even with these difficulties we were still able to find all 5 of our points in a relatively short time finishing before the other teams and finding points from previous years exercises that were still in the woods which Dr. Hupy was searching for using a GPS unit. 

Conclusion

This activity went quite well overall. The weather and lack of leaves on the trees were huge contributors to this result. The preparation in class for this exercise in previous weeks was also very helpful in the execution. All the groups found all of their points in order for the most part. This coming week we will be creating our own orienteering course at the priory using GPS units and Arcmap to plot the points on a map and then go into the woods find the locations and mark the trees for future classes to navigate. It will interesting to see how well the GPS units do in the woods with leaf cover and large elevation changes throughout the property.