Acoraceae

• Acorus calamus L., Sweetflag, Native, Larimer Co., Photos Phytoimages, USDA_Plants

Adoxaceae

• Adoxa moschatellina L., Muskroot, Native, Rare, Photos Phytoimages, USDA_Plants

• Sambucus nigra L. ssp. canadensis (L.) R. bolli, Common elderberry, Synonyms: Sambucus canadensis L., Introduced, Larimer Co., Photos Phytoimages, USDA_Plants

• Sambucus racemosa L., Red Elderberry, Red-berrried elder, Synonyms: Sambucus racemosa var. melanocarpa (A. Gray) McMinn, Sambucus racemosa var. microbotrys (Rydb.) Kearn. & Peeb., Native, Common, Photos Phytoimages, USDA_Plants

• Viburnum edule Raf., Squashberry, Synonyms: Viburnum pauciflorum Pylaie ex Torr. & Gray, Native, Common, Photos Phytoimages, USDA_Plants

Agavaceae

• Leucocrinum montanum Nutt. ex A.Gray, Sand Lily, Common sand lily, Star lily, Native, Common, Photos Phytoimages, USDA_Plants

• Yucca glauca Nutt., Great plains yucca, soapweed, Spanish bayonet, Native, Larimer Co., Photos Phytoimages, USDA_Plants

Alismataceae

• Alisma triviale Pursh, Northern water-plantain, Synonyms: Alisma plantago-aquatica L. var. americanum Schult., Native, Larimer Co., Photos Phytoimages, USDA_Plants

• Sagittaria brevirostra Mack. & Bush, Shortbeak arrowhead, Native, Larimer Co., Photos Phytoimages, USDA_Plants

• Sagittaria cuneata Sheldon, Arumleaf, Arrowhead, Native, Larimer Co., Photos Phytoimages, USDA_Plants

• Sagittaria latifolia Willd., Broadleaf arrowhead, Native, Larimer Co., Photos Phytoimages, USDA_Plants

Alliaceae

• Allium cernuum Roth, Nodding onion, Native, Common, Photos Phytoimages, USDA_Plants

• Allium geyeri S.Watson, Geyer onion, Native, Common, Photos Phytoimages, USDA_Plants

• Allium textile A. Nelson & J. F. Macbr., Textile onion, Native, Larimer Co., Photos Phytoimages, USDA_Plants

Amaranthaceae

• Amaranthus albus L., Tumble pigweed, Synonyms: A. pubescens (Uline & Bray) Rydb., Introduced, Larimer Co., Photos Phytoimages, USDA_Plants

• Amaranthus arenicola I. M. Johnst., Sandhill amaranth, Synonyms: A. torreyi (A. Gray) Benth., Native, Larimer Co., Photos Phytoimages, USDA_Plants

• Amaranthus blitoides S.Watson, Mat amaranth, Prostrate pigweed, Synonyms: A. graecizans L., Native, Abundance - Unknown, Photos Phytoimages, USDA_Plants

• Amaranthus powellii S. Watson, Powell's amaranth, Native, Larimer Co., Photos Phytoimages, USDA_Plants

• Amaranthus retroflexus L., Redroot amaranth, Introduced, Common, Photos Phytoimages, USDA_Plants

• Froelichia gracilis (Hook.) Moq., Slender snakecotton, Native, Larimer Co., Photos Phytoimages, USDA_Plants

Anacardiaceae

• Rhus glabra L., Smooth sumac, Native, Larimer Co., Photos Phytoimages, USDA_Plants

• Rhus trilobata Nutt., Skunkbush sumac, Synonyms: Rhus aromatica Aiton [considered a separate species on USDA Plants, other sources], Native, Common, Photos Phytoimages, USDA_Plants

• Toxicodendron rydbergii (Small ex Rydb.) Greene, Western poison ivy, Native, Larimer Co., Photos Phytoimages, USDA_Plants