Vegetation Survey of the Cranberry Pool lmpoundment of the

Missisquoi National Wildlife Refuge Swanton, Vermont

September 7, 2000

Submitted to: Missisquoi National Wildlife Refuge

U.S. Fish and Wildlife Service 371 North River Street

Swanton, Vermont, 05488

Avery Beyor Jr. P.O. Box206

Highgate, VT 05459

Methods This survey was conducted using the U.S. Fish and Wildlife Service (USFWS) moist soil

survey protocol (Internal Document). It utilizes a centric systematic area sampling method. This was used for several reasons, 1) it meets USFWS requirements for vegetation surveys, 2) simplicity of application in the field, and 3) assurance that vegetation is sampled evenly across the entire area.

Each impoundment is divided into square blocks of equal dimension and a sampling station is established at the center of each block (Figure 1). The dimensions for the sides of the each sample block were obtained through the use of the following formulas.

1. unit size (acres) I number of samples desired = block size (acres) 2. block size (acres) *43,560 ft2 =block size (ft2)

3. block size (ft2)112 = length of 1 side of block.

Figure 1 . Diagrammatic representation of centric systematic area sampling method

• • • • • • • • • • • • • • • •

• Sample Station Osample Block

• • • • • • • • • • • •

Since we desired one sample point for every 2 acres and the impoundment size is approximately 300 acres of actual marsh then we determined that 150 sample points would be necessary. Therefore by plugging these numbers into the formula above we came up with a side length of295 feet. Due to map scale constraints though, we modified this length to 310 feet. This increased our block sample sizes by 0.2 acres. Therefore our actual block sizes were 2.2 acres, but due to the size of the area to be surveyed we felt that this would not effect the outcome or accuracy of our sampling.

In order to establish a grid within the Cranberry Pool area we established a base line along the longest section of straight dike. This section of dike ran North by Northwest. Using field station operation maps we established the base line then ran transects that represented the center lines of the sampling blocks (Figure 2). Each of these transects was 310 ft. from the adjacent transect. They were run perpendicular to the base line on a bearing of 248 ° magnetic

SITES

1' North

EAOOUART

'\

(Southwest). The sample stations were then located by pacing along the transect for 155 feet for the first sample station on each transect and then 310 feet for each station thereafter. Each transect start point is permanently marked with a 6 foot long metal stake and a metal tag is attached to it that indicated the transect number.

According to the USFWS protocol sampling should take place twice annually. Once in mid to late summer with the peak occurrence of plants that flower or senesce. The second period should coincide with the peak period of above ground vegetation biomass. Only one sampling period occurred this year due to time and funding constraints.

Plant occurrence data was collected in a 1 meter square area that was located in the middle of each sampling block. A sampling square was constructed out of Y2 inch PVC piping and 4 90° PVC elbows. Each plant species was identified using Tiner's Field Guide to Nontidal Wetland Identification (1988) or Newcomb's Wildflower Guide (1977). The 6 dominant plant species within each sample were then recorded. Water was included only if there were not six plants within the sample area. For each plant species its density was recorded on a standardized data sheet according to the following scale:

A= 00 - 05 % Coverage B = 06 - 25 % Coverage C = 26 - 50 % Coverage D = 51 - 75 % Coverage E = 76 - 95 % Coverage F = 96 - 100% Coverage

Once all data was collected it was then analyzed in order to determine the percent cover of each species that was detected during the survey. This was done by taking the letter value for each of the species and converting it into a percentage value. The median value was used for each of the letter values. A= 2.5%, B = 15.5%, C = 38%, D = 63%, E = 85.5%, and F = 97.5%. Then the values for each species were summed and then divided the by the total number of sample stations in the survey unit, in this case 146.

Results 19 different species of plant were identified in this survey (Appendix A). They are as

follows, wild rice (Zizania aquatica), Sedges (Carex species.), Big-leaved Arrowhead (Sagittaria latifolia), Pennsylvania Smartweed (Polygonum pennsylvanicum), Great Bur-reed (Sparganium eurycarpum), Buttonbush (CepJuilanthus occidentalis), White Water Lily (Nymphaea odorata), Yellow Pond Lily (Nuphar luteum), Red Maple (Acer rubrum) Sensitive Fem (Onoc/ea sensibi/is), White Oak (Quercus alba), Coontail (Ceratophyllum demersum), Soft-stemmed Bulrush (Scirpus validus), Duck weed (Lemna species), Pickerel Weed (Pontederia cordata), Water Smartweed (Polygonum punctatum), Common Ragweed (Ambrosia artemisiifolia), Grass species (Gramineae), and Purple-leaved Willow-herb (Epi/obium coloratum). The average percent covers are shown in Table 1.

\

Table 1. Average percent covers for plant species identified during the Fall of 2000, in Cranbeny Pool Mi · · NWR, S V

' SS1SQU01 wanton, ermont.

Species Average Species Average Percent Percent Cover Cover

Water 66.41 Duckweed 1.39

Wild Rice 29.45 Red Maple 1.36

Buttonbush 16.81 Yellow Pond Lily 1.35

Arrowhead 9.61 Pickerel Weed 1.18

Carex Species 9.61 White Oak 0.52

Pennsylvania 9.02 Grass Species 0.43 Smartweed

White Water Lily 8.39 Water Smartweed 0.26

Coontail 7.07 Great Bur-reed 0.14

Purple-leaved 3.26 Sensitive Fem 0.12 Willow-herb

Soft-stemmed 3.14 Ragweed 0.11 Bulrush

Discussion Cranberry Pool is a flooded impoundment and it would therefore be reasonable to assume

that more than 66% would be covered with water. More than 66% is covered in water but some of it is in the form of saturated soil and other areas are covered by floating mats of vegetation and detritus. This makes it appear to be vegetated until it is disturbed. For purposes oftrus survey these area where considered as having no water.

As can be seen from Table 1, Wild Rice had the greatest percent cover of all plant species observed in the pool. Its distribution tended to be very even, with equal amounts in the North and South ends of the pool. It occurred heavily in areas with floating mats of vegetation as well as in inundated areas.

Buttonbush was the second greatest percent cover of all species in the pool and its distribution was very scattered. It tended to occur more in the western side of the pool but also occurred with some regularity in the eastern side, especially in the northern end of the pool.

Arrowhead and Sedges were both tied for third in percent cover. They were very evenly distributed and occurred in every area of the pool, although not in very abundant numbers. This may be misleading in the case of Arrowhead due to the fact that it was starting to senesce. In some cases all of the leaves were missing and only the flower head was available for identification purposes. Its actual distribution may be greater than measured.

Pennsylvania Smartweed had the fifth most percent coverage in the pool. Its distribution tended to be towards the Northern end of the pool, especially along the open water channel that ran North by Northwest along the dike used for our baseline.

White Water Lily had the sixth most percent coverage and was located mostly in the deeper water areas of the pool such as in the open water channel that ran along our base line dike and in the numerous open water pools found throughout the impoundment.

Coontail was found in the open water pool areas, it also occurred in areas where there were substantial numbers of White Water Lily. It had the seventh most percent coverage in the pool and tended to be distributed more towards the middle and North end of the pool.

Purple-leaved Willow-herb had the eighth most percent coverage and was concentrated n the Southern end of the pool. It seemed to prefer growing on the floating mats of dead and decaying vegetation. It was only found in 3 locations that were North of transect 10.

Soft-stemmed Bulrush had the ninth most percent coverage. Its distribution was almost solely in the Northern end of the pool along the channel that ran adjacent to the base line dike.

Duckweed had the lOlb most percent coverage and was concentrated in the Northern end of the pool. It was scattered variously among the open water pools and the areas with heavy growth ofButtonbush and Wild Rice.

Red Maple was 11 lb in coverage due to the fact that when it was present in a sample plot it tended, due to its size, to cover the entire point. It was only found in three plots. Two of these were in the Southeastern end of the pool on an exposed ground area that supported lots of trees and fems. The other was in the Northwestern end of the pool where an isolated tree was present.

Yell ow Pond Lily was found in scattered areas of the pool, but almost never mixed in with White Water Lily. It had the 12th most percent coverage of species recorded. It was distributed along the channels within the pool that tended to have slightly deeper water that the rest of the pool.

Pickerel Weed had the 13th most percent coverage and was found primarily in the Northern end of the pool along the channel that ran next to the base line dike. I believe that this species is actually more abundant in the pool than is shown by this survey due to its tendency to grow at the toe of the dike. This almost always made it fall outside of the sample area because the first sample was taken 155 feet away from the dike. Numerous areas of Pickerel weed were observed but only a few made it into the survey areas.

White Oak, Grasses, Water Smartweed, Great Bur-reed, Sensitive Fern, and Ragweed were all observed in at least one sample plot, but were not a significant source of plant material in the pool. Their percent covers ranged from 0.52% for White Oak to 0.11 % for Ragweed. These species appear to be isolated from other plants of the same species. The two notable exceptions are White Oak and Sensitive Fern. Both of these species are found with other White Oaks and Sensitive Ferns within a stand of trees in the Southeastern corner of the pool.

Literature Cited)

Newcomb, L. 1977. Newcomb's Wildflower Guide, Little, Brown and Company, Boston, MA. 490 pp.

Tiner, R. W., Jr. 1988. Field Guide to Nontidal Wetland Identification. Maryland Department of Natural Resources, Annapolis, MD and U.S. Fish and Wildlife Service, Newton Comer, MA. Cooperative Publication. 283 pp. + plates.

U.S. Fish and Wildlife Service. Vegetation Sampling Procedure. Internal Document. 5 pp.

Appendix A Missisquoi National Wildlife Refuge Vegetation Survey Cranbeny Pool Conducted By: Avery Beyor 21 August through 5 September, 2000

"C - co Q) c: ·- Q) "i5 c: "C .... CL Q) • "C COQ) .!..

o a. co >w :::i w ·- en w >. ~ m a. 0::: x .; ll>f::: - ..... E -c ~ > gco co ~ co :: co g wE ~ co en ~ u <: CLen (.') ~

.r:: I/) ::I .0 c: 0 s m

Species

~ .52

~I~ ...J "C

Q)

> co Q)

I Q)

e.-e ::I Q)

Q)

a. co ~ "C Q)

0::: T~lfWMt! ~tMtlflif M!WlMM mmtwm '!il%Mf% t@fS7.45.

9:...£ .;'.·'.·'.•··

~=~=;:~~=~:l~lJ. f:]Jff.~l~ T1-2 85.5 15.5 T1-3 I 15.51 38.0I 15.51 I 2.51 15.5

15.5

38.0 15.5 T2-3 I 97.51 2.51 2.51 I I 15.5 T2-4 I 97.51 I 15.51 I I 15.5 T2-5 I 38.0I 38.0I 2.51 I I 63.0 T2-6 I 97.51 2.51 2.5 lil~J?. :~it<,':'';"· T3-2 15.5 38.0 15.51 I 15.5 T3-3 2.5 38.0 63.0 15.5 T3-4 2.5 I 97.51 T3-5 97.5 T3-6 38.0 38.0 38.0 T3-7 2.5 63.0 38.0 15.51 I I 15.5 T3-8 15.5 15.5 15.5 2.51 I I 97.5 T3-9 85.5 15.5 63.0 T3-10 38.0 15.5 15.51 15.51 I 2.5

15.5 T4-3 I 85.51 38.0I 15.51 I I 63.0I I I 2.5 T 4-4 I I I I I I 97 .5 T4-5 I 15.51 15.51 38.0I I I 15.51 38.0 T4-6 I 38.0I I 15.51 I I 15.51 I I 63.0 T4-7 I 85.51 I I I I 15.51 I I 63.0 T4-8 I 15.51 15.51 15.51 I I 2.51 I I 15.5

., T4-9 63.0

E Q)

lJ.. Cl> > E I/) c: Q)

en

.:it:. co 0 Q)

;t::

~

co -c: 0 0 ()

:?:o ::J "C c: 0 CL

~ Qi >-

.r:: I/)

2 ::I m "C Q)

E E Q)

1;)

~ 0 en

"C Q)

~ .lit. 0 ::I 0

"C Q) Q)

~ ~ ~ 0

0.:

"C Q)

~ Cl co

0:::

"C Q) Q)

~ co E en ..... Q)

~ ~

ci en ~ e! (.')

TS-2 15.5 38.0 38.0 15.5 85.5 T5-3 15.5 63.0 85.5 38.0 T5-4 2.5 97.5 85.5 T5-5 15.5 97.5 85.5 T5-6 2.5 15.5 T5-7 63.0 15.5 63.0

63.0I I I 38.0 15.51 I I 15.5 ~

T5-8 97.5 15.5 T5-9 15.5 2.5 T5-10 2.5 38.0 2.5 T~1·.,,.. 85.5 tf:: .·:::·-::::.

85.51 85.51 15.5 38.0I 85.5 63.01 ':::.:.'.>: t ?$.< I -:·:.t . J, 15.S th,:: .x •t:fo·

T6-2 38.0 15.5 85.5 15.5 38.0 T6-3 63.0 2.5 63.0 2.5 T6-4 I 15.51 I I I I 97.5 15.5 2.5 T6-5 I I I I I I 97.5 15.5 T6-6 I 38.0I I I 15.51 I 38.0I 38.0I I 2.5 2.5 15.5 T6-7 I 15.51 I I I I 85.5 85.5 T6-8 I 15.51 15.51 I I I 63.0I 85.5 W,~1.miti':.h::: * •381Q.IED111~J?J;)J±~J~!§]M@WWMHtfA:; r······~~-fJ::;. ··· :::.BlliMEil2fammlx:;$!Jl@l@M~iW:T:.-:-1 ,.,,: 38.iQJ®tWJ!Ml· .. ;·,:.:":::· .Jllit.1illWJ@W&ili#.: ll}:: t /: TI-2 I 38.0I 2.51 15.51 I I 85.51 I I 15.5 TI-3 I 85.51 15.51 15.51 I I 63.0 T7-4 I I I I I I 97.51 I 2.51 I I I I 15.51 I 2.5 TI-5 I 15.51 I 2.51 I I 63.0I 85.51 I I I I I 2.5 TI-6 I 15.51 I I I I 97.51 I 15.51 I I I I 38.0 TI-7 85.5 97.5 2.5 Tai~rn1w.~ 'i:+:=::Vi4$~s ta .ti>: ®£K:2-iS n@m.~r4 .: Arws:t;lftl®# f.!t:::@.i:t% rn&a ili!HM mearo mnmini :: :d~hs ,~@tMJ: rnrn:m ::§Jf:E mm;.w T8-2 97.5 63.0 15.5 T8-3 I 2.51 38.0I 15.51 I I 63.0I I I I I I I I 15.5 TS-4 I I I I I I 97.51 I I I I I I 15.51 I 2.5 T8-5 I 2.51 I I I I 85.51 97.5 T8-6 I 85.51 15.51 38.0I I I 38.0I I I 15.5 T8-7 I 85.51 I 38.0I I I 63.0I I I I I I I 2.5 t~IWlW '.' +JW2t5 t'.lWiS~ $F:··2.5 ::mrnams: :::'\&till @~5~5 fMW::lf 001%@ lt&lff ~?!Vi''! rwg;· T9-2 97.5 97.5 85.5 T9-3 2.5 15.5 2.51 63.0 15.51 85.5 63.0 T9-4 2.5 63.0 2.5 63.0 T9-5 15.5 38.0 85.5 2.5 T9-6 97.5 85.51 2.5 85.5 T9-7 97.5 15.51 2.5 38.0 Trl:~FtW I : •.• 2.s1w::rn:::r?'-F· • .:.: -.;;··· '·l'':tnt:wmn:·· ,_, 9lf5lfilf.t:?t 97.51l%W.FBk·r ". :\JfilfaJtlltF·. '' p: @@Bffliili®F':,,,. m ·t :Nfai@if#V'i ;:-:: 1

T10-2 63.0I I 15.51 2.5 97.5 63.0 2.5 T10-3 2.51 2.51 63.0 2.5 85.51 I 63.0 T10-4 2.5 97.5 2.5 T10-5 2.51 63.0 97.5 15.5 T10-6 15.51 I 15.51 2.5 63.0I 63.0

-' 1T10·7 85.51 I 38.0 2.5 2.5 Tt'h1 ·

1 ·rw~1w~ :'9>,sa;o 91.51%J<:s 85.51 :::m:::;p~ WMH rs.sr IMF r r , ··snIV'" 1

T11-2 I 63.0I I 15.51 I I 2.5 63.0 T11-3 I I I 15.51 I 2.51 85.51 38.0 T11-4 I I I I I I 97.5 38.0I 63.0 2.5 T11-5 I 63.0I I 2.51 I I 63.0 15.5 15.5 2.5 T11-6 I 15.51 2.51 I I I 85.51 63.0 r1z:t1 1 ss~&t 1 · 1.5.sf 2.51 ,,,,,:,., · l 97,s # ]r2.5 · . 2~s ::\ t T12-2 I I I I I I 97.5 85.5 15.5 2.5 T12-3 I 85.51 I 15.51 15.51 I 63.0 2.5 T12-4 I 15.51 I 15.51 I I 97.51 85.5 2.5 T12-5 I 85.51 I 15.51 15.51 I 63.0 2.5 T12-6 I 63.0I I 15.51 I I 97.51 63.0 T12-7 2.5 2.5 2.5 97.5 97.5 T1.3.M> :: t $ th., :=::;:=::::WtK .,,: illl#l :::, 97.5 .:WM~7;$ ' ii.¥ ::·. wtt W@:.,,,, rn .@Mlk.8 "'jt :fj;~~5 ,;. «

T13-2 15.5 97.5 63.0 15.5 T13-3 I 2.51 I 2.51 I I 97.51 85.5 2.5 T13-4 I 97.51 I 2.51 2.51 I 63.0I 2.5 T13-5 I 63.0I I 15.51 38.0I I 15.5 T13-6 15.5 97.5 85.5 2.5 T1:~mr; ::: :::~~a~~rrr :i~~I~?;::::::;~· · '.t~=ri@~mrtt -:$::· ~{rm §~ , ·=~::·=:::::::t :~~~~m~~~\lr::::: :~:( · ~t~ w.r~jft> ~~~tif. r:mM~tr~~- ·mtrr f~Wi~f:t 0t.~x:- :>~-f~ t~rt.~J#r ;ls:s ·;;JMQ ::es~o T14-2 15.5 97.5 63.0 T14-3 T14-4 T14-5 Tf$.M,W='''' T15-2 T15-3 T15-4 T15-5 t lf$ ,$W¥· T16-2 T16-3 T16-4 T16-5 T16-6 f'f'Vt T17-2 T17-3 T17-4 T17-5 T17-6 T1S..1 T18-2 T18-3 T18-4

~ 'T18-5 T1St1

2 .51 I 2.51 I I 85.51 85.5 97.51 I 15.51 I I 38.0 85.51 I 15.51 I I 97.5

'''·'''·1:~t11mwea.01:mwa;zartMt· =r\;1.n1t=ttJFW~1~s1mrnw rt 97.5

2.5 15.5 97.51 38.0 97.5

63.0I 15.51 15.51 38.0 97.5 '''-Wt>:3in mvaero V!:&%t1li r x';zs ·.~~-:r.s ,. 9tE5 mwv'

15.5 2.5 97.5 85.51 I I 15.51 I 97.5 15.51 I I 2.51 I 97.51 85.5 85.51 I I 2.51 I 97.51 15.5

2.51 I 15.51 I I 85.5 ests1 ··· 1s.s1 ,~s.ot · r:: · · 1 91.s1 ::::

15.5 2.5 15.5

97.5 2.5 15.5 2.5 15~5 15.5 '''.1.S.5 15.5 2.5

2.5 2.5 15.5 15.5

63.0 38.0 2.5

15 5 p:~~-<':·. ... ·.:t.~·~·

15.5 2.51''''''

97.5 97.51 15.5 97.5 2.5

97.51 85.5 97.SHr· 97.51 63.0 97.5 97.5 97.5 85.5 65.5 .:. 85.5

15.5 2.5

:::::~:ea~o · ~ ;)fM w~@~~iir:: ;:;: -==~~i· {@Nff.:i~~:==t • t~tW~illt :•: ::w.:r: fifft~~rr ::~-· ::~t 85.5 63.0

15.5 63.0 38.0 15.5

<&Wif =i@Wff'I ..;.: )%@:,:;gf::::::l 'tltm:: n1wt ">::::\,tWfYP,"W'.tW====f 'imt'\Wt:::·· ;;: ''l!@m=mj>=m-85.5 15.5

15.5 15.5

15.5

'\/ ' @1i: :;tt} ::::1~1~1: ::~t~r

85.5 63.0 15.5

15.5 2.5

~ ~

. •.

>

2.5 ( 38.0 €¥ }f: . ,.

15.5 -2.5 2.5

63.0 15.5 2.5 -

2:5 {~ .~:_;::: >-

·::: ..

T19-2 2.5 38.0 38.0 85.5 38.0 38.0 T19-3 15.5 15.5 85.5 15.5 T19-4 15.5 38.0 85.5 15.5 T19-5 2.5 97.5 2.5 120:1 ' 63l0 ' ; }~~@~tt I . :··:·:;:;:::; .... )(: 97.5 "\:::. :.:/" .:::;· :::::::c i~l~ ::;: ):::·: }'N:f'''' wrn !'(''':;:;: 2.5 ;:qw. :·:· :t.W: ~ ·:;:::·:·: I

T20-2 85.5 85.5 97.5 15.5 T20-3 63.0 85.5 15.5 15.5 T20-4 38.0 63.0 97.5 2.5 15.5 T20-5 63.0 38.0 15.5 85.5 2.5 T20-6 85.5 15.5 63.0 15.5 2.5 T2t .. 1 38.-0 15,5 ·1s.s .. \k •s1.s ::;::~ ~:: ·:•: •· .,.,:::' +: 63.0 -t·· :.:.:~ ·;·:· .;

T21-2 2.5 97.5 97.5 2.5 T21-3 2.5 38.0 97.5 2.5 2.5 T21-4 97.5 38.0 15.5 2.5 T21-5 97.5 38.0 T22;+1 2:5 - - 85,5 ·:1S;5 mt 8$.5 t::}::;. !. ·w ·•'· :;:· lt :-:-

<:iif.i'' '"::\::: :::::·.

T22-2 97.5 15.5 63.0 2.5 T22-3 15.5 2.5 38.0 2.5 15.5 T22-4 63.0 38.0 38.0 85.5 T22-5 97.5 2.5 2.5 97.5 T2$ltj :2$ . 85.5 . ~ ... ~;»: 63.0 $~:~.;.; 38.0 .&%: Y; ·~

«_., ' ~ ... .::: :_ .. -:--.. :-:-:.:-: .:w.~@ ~mKtt.m ··; Jr·. ,4- ~o'Jf..

T23-2 38.0 15.5 85.5 63.0 T23-3 2.5 2.5 85.5 85.5 T23-4 63.0 2.5 2.5 38.0 Sum of Percent Cover 4300.0 1403.0 1403.0 1317.5 20.5 9695.5 2454.0 1224.5 476.5 198.5 18.0 76.0 1031.5 197.5 459.0 202.5 172.0 15.5 38.0 63.0 Total Sample Stations 146 146 146 146 146 146 146 146 146 146 146 146 146 146 146 146 146 146 146 146 Average Percent Cover 29.45 9.61 9.61 9.02 0.14 66.41 16.81 8.39 3.26 1.36 0.12 0.52 7.07 1.35 3.14 1.39 1.18 0.11 0.26 0.43

z:. z:. "O :.:; E

:.:; "O - cu Q) "O .... "O Q) c

~ ....

~€ Q) Q) Q)

·c; ·c= -o .r::. Q) LL

~ E "O Q)

"O "O "O cu Q) .!. - Q) .:.t. Q) ~ Q.. Q) ci. cu Ill cu cu Q) 0.. cu E Q) Q) ci. 0 > Q) ::I ::I ~ ~ s::. Q) Q) Q) Q) Cl) Q)

~~ m .c cu > 0 Q) s::. ~ ~ Cl) Q) ii: .r::. di ~ cu ~ .... ~ a. .... c :? :E ~ - Ill )( ~ - Q) Q) - ~ 2 ~ E "O ~ c cu cu Q) 0 - e.g Ill - c ~ Q) Cl ~ cu 0

~ E ~ - ~ "O c :c 0 ¢::: - 0 .:.t. e t:: cu .r::. 0 cu ~~ cu ~

cu ~

::I ~ er ~

Q) Q)

~ 0 Q) 0 ::I :::::I 0:: Cl) 0 < Q.. (/) C9 m 0:: (/) 0 >- en m 0 0: C9

Species

~