Washington County

Showing 1–50 of 533.

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  Abutilon theophrasti Medik. Introduced ABTH

  velvetleaf · Malvaceae
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  Acalypha rhomboidea Raf. Native ACRH

  common threeseed mercury · Euphorbiaceae
• 
  Acalypha virginica L. Native ACVI

  Virginia threeseed mercury · Euphorbiaceae
• 
  Acer negundo L. Native ACNE2

  boxelder · Aceraceae
• 
  Acer saccharinum L. Native ACSA2

  silver maple · Aceraceae
• 
  Achillea millefolium L. Both ACMI2

  common yarrow · Asteraceae
• 
  Achillea millefolium L. var. occidentalis DC. Native ACMIO

  western yarrow · Asteraceae
• 
  Adiantum pedatum L. Native ADPE

  northern maidenhair · Pteridaceae
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  Ageratina altissima (L.) R.M. King & H. Rob. Native AGAL5

  white snakeroot · Asteraceae
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  Ageratina altissima (L.) R.M. King & H. Rob. var. altissima Native AGALA

  white snakeroot · Asteraceae
• 
  Agrostis hyemalis (Walter) Britton, Sterns & Poggenb. Native AGHY

  winter bentgrass · Poaceae
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  Agrostis perennans (Walter) Tuck. Native AGPE

  upland bentgrass · Poaceae
• 
  Agrostis stolonifera L. Introduced AGST2

  creeping bentgrass · Poaceae
• 
  Alisma subcordatum Raf. Native ALSU

  American water plantain · Alismataceae
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  Alopecurus carolinianus Walter Native ALCA4

  Carolina foxtail · Poaceae
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  Amaranthus retroflexus L. Native AMRE

  redroot amaranth · Amaranthaceae
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  Amaranthus tuberculatus (Moq.) Sauer Native AMTU

  roughfruit amaranth · Amaranthaceae
• 
  Ambrosia artemisiifolia L. Both AMAR2

  annual ragweed · Asteraceae
• 
  Ambrosia artemisiifolia L. var. elatior (L.) Descourtils Introduced AMARE

  annual ragweed · Asteraceae
• 
  Ambrosia psilostachya DC. Native AMPS

  Cuman ragweed · Asteraceae
• 
  Ambrosia trifida L. Native AMTR

  great ragweed · Asteraceae
• 
  Ambrosia trifida L. var. trifida Native AMTRT2

  great ragweed · Asteraceae
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  Amelanchier arborea (Michx. f.) Fernald Native AMAR3

  common serviceberry · Rosaceae
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  Amelanchier arborea (Michx. f.) Fernald var. arborea Native AMARA4

  common serviceberry · Rosaceae
• 
  Ammannia coccinea Rottb. Native AMCO

  valley redstem · Lythraceae
• 
  Amorpha canescens Pursh Native AMCA6

  leadplant · Fabaceae
• 
  Amorpha fruticosa L. Native AMFR

  false indigo bush · Fabaceae
• 
  Andropogon gerardii Vitman Native ANGE

  big bluestem · Poaceae
• 
  Anemone canadensis L. Native ANCA8

  Canadian anemone · Ranunculaceae
• 
  Anemone virginiana L. Native ANVI3

  tall thimbleweed · Ranunculaceae
• 
  Anemone virginiana L. var. virginiana Native ANVIV2

  tall thimbleweed · Ranunculaceae
• ⚘
  Antennaria neglecta Greene Native ANNE

  field pussytoes · Asteraceae
• 
  Apocynum cannabinum L. Native APCA

  Indianhemp · Apocynaceae
• 
  Aquilegia canadensis L. Native AQCA

  red columbine · Ranunculaceae
• 
  Aralia nudicaulis L. Native ARNU2

  wild sarsaparilla · Araliaceae
• 
  Arisaema triphyllum (L.) Schott Native ARTR

  Jack in the pulpit · Araceae
• 
  Arisaema triphyllum (L.) Schott ssp. triphyllum Native ARTRT3

  Jack in the pulpit · Araceae
• 
  Aristida basiramea Engelm. ex Vasey Native ARBA2

  forked threeawn · Poaceae
• 
  Aristida oligantha Michx. Native AROL

  prairie threeawn · Poaceae
• 
  Arnoglossum plantagineum Raf. Native ARPL4

  groovestem Indian plantain · Asteraceae
• 
  Artemisia filifolia Torr. Native ARFI2

  sand sagebrush · Asteraceae
• 
  Artemisia ludoviciana Nutt. Both ARLU

  white sagebrush · Asteraceae
• 
  Artemisia ludoviciana Nutt. ssp. ludoviciana Native ARLUL2

  white sagebrush · Asteraceae
• 
  Asarum canadense L. Native ASCA

  Canadian wildginger · Aristolochiaceae
• 
  Asclepias incarnata L. Native ASIN

  swamp milkweed · Asclepiadaceae
• 
  Asclepias incarnata L. ssp. incarnata Native ASINI

  swamp milkweed · Asclepiadaceae
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  Asclepias tuberosa L. Native ASTU

  butterfly milkweed · Asclepiadaceae
• 
  Asclepias tuberosa L. ssp. interior Woodson Native ASTUI

  butterfly milkweed · Asclepiadaceae
• 
  Asclepias verticillata L. Native ASVE

  whorled milkweed · Asclepiadaceae
• 
  Astragalus canadensis L. Native ASCA11

  Canadian milkvetch · Fabaceae