Reference: Weaver, J.E North American Prairie. Johansen Publishing Co., Lincoln, NE.

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1 Minnesta Bilgical Survey Wetland Prairie System Cnditin Ranking Guidelines (This is a wrking dcument that is peridically revised as new infrmatin is available) May 2014 versin Cnditin Ranks fr Native Plant Cmmunities Cnditin Ranks fr native plant cmmunities reflect the degree f eclgical integrity f a specific ccurrence f a native plant cmmunity. Cnditin Ranks are assigned by cnsidering species cmpsitin, vegetatin structure, eclgical prcesses and functins, level f human disturbance, presence f extic species, and ther factrs. Cnditin Ranks are assigned n a scale f A t D. A-rank ccurrences have excellent eclgical integrity. They have species cmpsitin, structure, and eclgical prcesses typical f the natural r histric range f the cmmunity and have been little degraded by recent human activity r invasive species. B-rank ccurrences have gd eclgical integrity. They include plant cmmunities with mdest degradatin r that were degraded in the past but have recvered and nw have relatively natural cmpsitin and structure. B-rank ccurrences nrmally will return t A-rank cnditin with prtectin r apprpriate management. C-rank ccurrences have fair eclgical integrity. They shw strng evidence f human-caused degradatin, but retain sme characteristic species and have sme ptential fr recvery with prtectin and management. D-rank ccurrences have pr eclgical integrity. The riginal cmpsitin and structure f the cmmunity have been severely altered by human-caused degradatin r invasin by extic species. They have little chance f recvery t their natural r histric cnditin. The Wetland Prairie System cntains the fllwing native plant cmmunity classes and types: WPn53 Nrthern Wet Prairie WPn53a Wet Seepage Prairie (Nrthern) WPn53b Wet Brush-Prairie (Nrthern) WPn53c Wet Prairie (Nrthern) WPn53d Wet Saline Prairie (Nrthern) WPs54 Suthern Wet Prairie WPs54a (Wet Seepage Prairie (Suthern)) WPs54b (Wet Prairie (Suthern)) WPs54c (Wet Saline Prairie (Suthern)) Fr infrmatin n the plant cmmunity classes and types in this System, please refer t the Wetland Prairie System in Field Guide t the Native Plant Cmmunities f Minnesta: The Prairie Parkland and Tallgrass Aspen Parklands Prvinces (MNDNR 2005) r Field Guide t the Native Plant Cmmunities f Minnesta: The Eastern Bradleaf Frest Prvince (MNDNR 2005). Fr checklists and distributin maps f native plant species in Minnesta, refer t the MNDNR s State Checklists n the MNDNR website at: 1) What is an A-rank Occurrence? Site has structure and cmpsitin free f human-caused degradatin frm vergrazing, draining, flding, prly-timed haying, siltatin, herbicide applicatin/drift, invasive species invasin, fertilizer drift, fire suppressin, tree planting, and ATV use. A-rank ccurrences are cnsidered high-quality prairie and typically have the fllwing cnditins: A diverse assemblage f native species is present, including decreaser species (see Weaver 1954) that decline with persistent mderate t heavy grazing (Table 1). Nte that Wet Saline Prairies (WPn53d, WPs54c) typically have lw diversity and abundance f frb species. 1

2 The vegetatin cmpsitin shws little evidence f degradatin in the frm f increased relative abundances f grazing increasers (Table 2). Nn-native, invasive species (Table 3) are absent r barely present with the exceptin f Kentucky bluegrass (Pa pratensis), which is almst universally present tday in wet prairies. Kentucky bluegrass is at mst a minr cnstituent f A-rank prairies. Site has a natural water regime (hydrlgy), such as n evidence that natural water table levels have been altered by ditching, irrigatin pumping, upslpe gravel mining, water impunding, etc. 2) What is a B-rank Occurrence? Site has structure and cmpsitin similar t that f an A-rank ccurrence, but has altered species abundances and richness due t mderate levels f degradatin frm vergrazing, prly-timed haying, wdy plant invasin, minr wetland drainage, fertilizer drift, minr herbicide expsure, invasive species, tree planting, r lw t mderate ATV use. B-rank ccurrences are cnsidered high-quality prairie and typically have the fllwing cnditins: Native species richness is high but sme decreaser species apprpriate t the site are missing, and ther decreaser species are much less cmmn than in A-rank sites (Table 1). Species that increase in respnse t human-caused degradatin are mre abundant than in A-rank ccurrences (Table 2). Examples include grazing increasers due t grazing r wdy species due t fire suppressin. The invasive species Kentucky bluegrass and redtp (Agrstis gigantea) may be present at mderate levels f infestatin, but ther invasive species are absent r barely present. Reed canary grass (Phalaris arundinacea), if present, is cnfined t narrw znes n the margins f the wetland. In sites that have been grazed, the grund surface may have minr cmpactin and hummcking frm livestck. 3) What is a C-rank Occurrence? Site is still dminated by native species, but has mderate t heavy degradatin frm vergrazing, wetland drainage, haying, fire suppressin, mderate herbicide expsure, siltatin, significant invasive species invasin, r tree planting. C-rank ccurrences are cnsidered fair-quality prairie and typically have the fllwing cnditins: Native graminids still dminate thrughut the site r c-dminate with shrubs, but verall plant species diversity is lw due t lss f species that decrease in abundance with persistent mderate t heavy grazing (Table 1). On sites degraded by grazing, heavy livestck traffic n wet sils breaks up the prairie turf and creates expsed bare sils prne t the invasin f invasive plant species. Native plant species that increase with grazing pressure are highly abundant (Table 2). Invasive species are mderately abundant, including Kentucky bluegrass, field sw thistle (Snchus arvensis), timthy (Phleum pretense), black medick (Medicag lupulina), white clver (Triflium repens), red clver (T. pratense), Alsike clver (T. hybridum), Canada thistle (Cirsium arvense), r redtp (Table 3). Reed canary grass may be present as discrete patches cvering n mre than 20% f the site r is cnfined t znes n the margins f deeper wet depressins. In sites grazed by cattle, the grund surface may be mderately cmpacted and hummcky. 2

3 4) What is a D-rank Occurrence? Site has been highly degraded and the native vegetatin has been severely altered, but enugh native species are present that the ccurrence can still be recgnized as the cmmunity type it was prir t being degraded. D-rank ccurrences are cnsidered pr-quality prairie and typically have the fllwing cnditins: Site is dminated by extic species, typically Kentucky bluegrass, quackgrass (Elymus [Agrpyrn] repens), and/r redtp, but native graminids are cmmn enugh fr the ccurrence t be recgnized as native prairie and nt ld field. The invasive species reed canary grass cvers n mre than 50% f the site. Overall native species richness is lw, as sensitive species such as grazing decreasers are absent. Disturbance increasers are highly abundant. In grazed sites, the grund surface is highly cmpacted and/r hummcky. In sites where herbicide has been applied repeatedly native frbs are absent. 5) Mapping ntes: Plygn sizes: Map A-D rank ccurrences that are 5 acres r larger. Map smaller ccurrences if they meet ne f the fllwing exceptins: It is within a larger area f native plant cmmunities imprtant fr cnservatin actin. It is habitat fr a rare species. It is ne f the very few ccurrences f the type in an LTA. It is A-r B-rank. If a large prairie has a dense area f reed canary grass at ne end but the rest is in gd cnditin, map the intact prairie and nt the reed canary grass-dminated areas unless native species are present within the reed canary grass-dminated zne, in which case map it all. If the reed canary-dminated zne is at least 2 acres in size, cnsider mapping it as a separate plygn. On rare ccasins, a recnstructed r restred prairie may be sufficiently diverse cnsisting f species and ectypes apprpriate fr its lcatin t be ranked as a native plant cmmunity. If such a site is virtually indiscernible frm a native ccurrence, it may be mapped and ranked accrding t the criteria in these guidelines, but plygn attributes r ther database entries shuld nte that it is restred/recnstructed. On sme landfrms, wet prairies may ccur in a cmplex msaic with ther cmmunities such as mesic prairie, related t variatin in micrtpgraphy. In such cases, where individual ccurrences f wet prairie cannt be mapped separately, the ccurrence may be mapped as part f a native plant cmmunity cmplex. Revised by Fred Harris and Rbert Dana 30 May 2014 Reference: Weaver, J.E Nrth American Prairie. Jhansen Publishing C., Lincln, NE. 3

4 Table 1. Examples f species that decrease with vergrazing 1 in Wet Prairie cmmunities: Cmmn Name Scientific Name Limited Distributin Fragrant false indig Amrpha nana* Big bluestem Andrpgn gerardii Sweet grass Anthxanthum hirtum Swamp milkweed Asclepias incarnata Shwy milkweed Asclepias specisa Canada milk-vetch Astragalus canadensis Buxbaum's sedge Carex buxbaumii Wd-sedge Carex tetanica Indian paintbrush Castellja cccinea Swamp thistle Cirsium muticum Small white lady-slipper Cypripedium candidum White prairie clver Dalea candida var. candida* Purple prairie clver Dalea purpurea Canadian tick-trefil Desmdium canadense* Flat-tpped aster Dellingeria umbellata Sptted Je-pye weed Eupatrium maculatum Nrthern gentian Gentiana affinis Nrthwestern MN saline prairie Bttle gentian Gentiana andrewsii Autumn sneezeweed Helenium autumnale Yellw star-grass Hypxis hirsuta Junegrass Keleria pyramidata Marsh vetchling Lathyrus palustris Rugh blazing star Liatris aspera Nrthern plains blazing star Liatris ligulistylis Gayfeather Liatris pycnstachya Michigan lily Lilium michiganense Wd lily Lilium philadelphicum* Kalm's lbelia Lbelia kalmii Great lbelia Lbelia siphilitica Pale-spiked lbelia Lbelia spicata Prairie lsestrife Lysimachia quadriflra Switchgrass Panicum virgatum Swamp lusewrt Pedicularis lancelatus Prairie phlx Phlx pilsa* Suthern MN Smth rattlesnakert Prenanthes racemsa* Virginia muntain mint Pycnanthemum virginianum Gray-headed cneflwer Ratibida pinnata Suthern MN Little bluestem Schizachyrium scparium Marsh skullcap Scutellaria galericulata Cup-plant Silphium perfliatum Suthern MN Upland white aster Slidag ptarmicides Riddell's gldenrd Slidag riddellii Indian grass Srghastrum nutans Alkali crd-grass Spartina gracilis Nrthwestern MN saline prairie Prairie crd-grass Spartina pectinata Prairie drpseed Sprblus heterlepis* Bg aster Symphytrichum breale Panicled aster Symphytrichum lancelatum New England aster Symphytrichum nvae-angliae Glssy-leaf aster Symphytrichum firmum Germander Teucrium canadense Tall meadw-rue Thalictrum dasycarpum Culver's rt Vernicastrum virginicum Glden alexanders Zizia aurea 1 species that appear t decrease in abundance with persistent mderate t heavy grazing *species that appear t be the mst sensitive t grazing 4

5 Table 2. Examples f species that increase with vergrazing 2 in Wet Prairie cmmunities: Cmmn Name Scientific Name Cmmn yarrw Achillea milleflium Ragweed Ambrsia spp. Clasping dgbane Apcynum sibiricum Heath aster Aster ericides Sartwell's sedge Carex sartwellii Sptted water-hemlck Cicuta maculata Field hrsetail Equisetum arvense Grass-leaved gldenrd Euthamia graminiflia Giant sunflwer Helianthus giganteus Sawtth sunflwer Helianthus grsseserratus Fxtail barley Hrdeum jubatum Baltic rush Juncus arcticus var. balticus Rugh bugleweed Lycpus asper Silverweed Ptentilla anserina Seaside crwft Ranunculus cymbalaria Swamp buttercup Ranunculus fascicularis Glden ragwrt Seneci aureus False glden ragwrt Late gldenrd Canada gldenrd Giant gldenrd Rugh drpseed Blue vervain Bunched irnweed Seneci pseudaureus Slidag altissima subsp. gilvcanescens Slidag canadensis Slidag gigantea Sprblus asper Verbena hastata Vernnia fasciculata 2 species that appear t increase in abundance with persistent mderate t heavy grazing Table 3. Examples f invasive species in Wet Prairie cmmunities: Cmmn Name Scientific Name Redtp Agrstis gigantea Spreading bentgrass Agrstis stlnifera Smth brme Brmus inermis Canada thistle Cirsium arvense Bull thistle Cirsium vulgare Hrseweed Cnyza canadensis Quackgrass Elymus repens Black medick Medicag lupulina Sweet clver Meliltus spp. Reed canary grass Phalaris arundinacea Timthy Phleum pratense Cmmn plantain Plantag majr Kentucky bluegrass Pa pratensis Eurpean alkali grass Puccinellia distans Cmmn buckthrn Rhamnus cathartica Field sw thistle Snchus arvensis Dandelin Taraxacum spp. Alsike clver Triflium hybridum Red clver Triflium pratense White clver Triflium repens Stinging nettle Urtica diica 5