Eurasian Watermilfoil Survey Guide (Draft)

1.       Use the GPS unit to locate your first point.  

2.       Once you are on your point secure the boat with front anchor.

3.       At this time fill in Point #, Initials of Surveyors, Date, Time, UTM Coordinates and Accuracy on the Eurasian Watermilfoil Data Sheet.

4.       Next, using the calibrated rake, measure the water depth.  Record the depth (in feet) in the box labeled Water Depth.

5.      Substrate Sampling

·         With the rake still in the water “feel” the substrate. 

·         Select one of the following substrate types: muck, peat, sand, gravel, or cobble/rubble.

·         Record the Substrate type on the Data Sheet.

·         Note:  If possible you may visually inspect the substrate to help with identification. 

6.      Plant sampling

·         After the depth is recorded take the macrophyte rake to the starboard (right) side of the boat and extend it out so that the rake head is approximately 3.0 feet away from the gunwale of the boat.

·         Pull the rake head toward the boat until the rake handle is roughly perpendicular to the waters surface.  (The rake head should travel approximately 2.5 feet along the substrate.)

·         Slowly pull rake to the surface and into the boat.

·         Take Abundance Ratings:

                                                                                       i.      Using Appendix I (Abundance Rating Guide) rate and record the overall aquatic plant abundance (Overall Abundance) on the rake head.

                                                                                     ii.      Also, using Appendix I, rate and record the eurasian watermilfoil abundance (EWM Abundance) on the rake head.

·         Next, take the plant samples from the rake and rake head and put them into the small plastic tub. 

·         Take one plant sample at a time and identify it.  Then put the correct plant letter code in the boxes under the Species Present column. 

·         If the plant is an exotic species take a voucher sample of the plant for future use. (Plant sampling continued below.)

7.      Plant Voucher

·         Only take voucher samples when there are enough structures available for identification.

·         All vouchers have a Voucher #.  (Voucher #’s go in order; 1,2,3…9,10,11…).  Write the voucher number on the data sheet.

·         Next, take the plant and insert it into a moist Ziploc bag.  On the Ziploc bag write the Date, Voucher #, Initials of Surveyor, and the Point #. 

·         Write the same information in the Plant Voucher Record Book (A write-in-the-rain field notebook).

·         Check the Plant Voucher Record Book to make sure the Voucher # is correct.

8.      Plant Sampling Continued

·         Go through the plastic bin until all plants that can be identified are, and return all native plants you have recorded.  Any native plants you can not identify take a voucher sample (see Plant Voucher above).

·         If the plant is an exotic, and you have already taken a voucher sample, put it in the bucket to be composted on shore later.

·         Once you have finished with the R, or starboard, side of the boat move the rake to the L, or port, side of the boat and repeat steps 5-7

9.       Enter any useful management information in the Notes section.

·         If eurasian watermilfoil is present indicate whether or not it is at the water’s surface. 

·         If there is an aquatic plant at the surface, but it is not eurasian watermilfoil, identify and record it.   

10.  Water Clarity

·         Water clarity tests will only be done at selected locations.  Most points will not have water clarity tests and therefore the Water Clarity box will be left blank. 

·         Using the Secchi Disk go to the starboard side of the boat.

·         Lower the Secchi Disk (while keeping track of depth reading) until you can not see it any more.  Then bring it back towards the surface until it is visible again. 

·         Record the depth in the Water Clarity box.

11.   Double check all the data on the Eurasian Watermilfoil Data Sheet.

12.   Pull up anchors and travel to the next Point # using the GPS.

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