List of dicotyledons of Montana
There are at least 2109 species of dicotyledons found in Montana according to the Montana Field Guide.  This is a list of Dicotyledoneae orders found in Montana. The Montana Natural Heritage Program has identified a number of dicot species as Species of Concern. Some of these species are exotics (not native to Montana).
The dicotyledons, also known as dicots, are a group of flowering plants whose seed typically has two embryonic leaves or cotyledons. There are around 199,350 species within this group. Flowering plants that are not dicotyledons are monocotyledons, typically having one embryonic leaf.
- List of Asters and Sunflowers of Montana, Order: Asterales
- List of Barberries and Buttercups of Montana, Order: Ranunculales
- List of Bedstraws and Madders of Montana, Order: Rubiales
- List of Bellflowers of Montana, Order: Campanulales
- List of Alders, Birches and Oaks of Montana, Order: Fagales
- List of Borage, Mints and Verbenas of Montana, Order: Lamiales
- List of Buckthorn and Grapes of Montana, Order: Rhamnales
- List of Buckwheats of Montana, Order: Polygonales
- List of Capers, Mignonette and Mustards of Montana, Order: Capparales
- List of Caryophyllales of Montana, Order: Caryophyllales
- Celastrales, Order: Celastrales
- List of Dipsacales of Montana, Order: Dipsacales
- List of Dogbane, Gentian and Milkweed of Montana, Order: Gentianales
- Dogwood, Order: Cornales
- List of Dwarf-mistletoe and Sandalwood of Montana, Order: Santalales
- List of Evening-primrose and Loosestrife of Montana, Order: Myrtales
- List of Flax of Montana, Order: Linales
- List of Fumary and Poppy of Montana, Order: Papaverales
- List of Geraniums, Impatiens and Woodsorrel of Montana, Order: Geraniales
- Ginger, Order: Aristolochiales
- Wild-ginger, Asarum caudatum
- List of Ginseng and Parsley of Montana, Order: Apiales
- List of Heaths, Wintergreens and Monotropes of Montana, Order: Ericales
- List of Mallows of Montana, Order: Malvales
- List of Creosote Bush, Maples and Sumacs of Montana, Order: Sapindales
- Milkworts, Order: Polygalales
- Oleasters, Order: Proteales
- List of Peas of Montana, Order: Fabales
- Peony, Order: Dilleniales
- Western Peony, Paeonia brownii
- List of Plantains of Montana, Order: Plantaginales
- List of Primrose of Montana, Order: Primulales
- List of Rosales of Montana, Order: Rosales
- List of Scrophulariales of Montana, Order: Scrophulariales
- List of Solanales of Montana, Order: Solanales
- List of Spurge of Montana, Order: Euphorbiales
- List of St. Johnswort and Waterwort of Montana, Order: Theales
- Sundews, Order: Nepenthales
- List of Urticales of Montana, Order: Urticales
- List of Violales of Montana, Order: Violales
- Water Milfoil, Order: Haloragales
- List of Water Lilies and Watershields of Montana, Order: Nymphaeales
- Water-starworts and Mare's-tails, Order: Callitrichales
- Mare's tails, Family: Hippuridaceae
- Common Mare's-tail, Hippuris vulgaris
- Water-starworts, Family: Callitrichaceae
- Mare's tails, Family: Hippuridaceae
- List of Poplars and Willows of Montana, Order: Salicales
- Rydberg, Per Axel PhD (1900). Catalogue of the flora of Montana and the Yellowstone National Park (PDF). New York: New York Botanical Garden.
- Rydberg, Per Axel PhD (1917). Flora of the Rocky Mountains and Adjacent Plains (PDF). New York: New York Botanical Garden.
- Rydberg, Per Axel PhD (1919). Key to the Rocky Mountain flora; Colorado, Utah, Wyoming, Idaho, Montana, Saskatchewan, Alberta, and parts of Nebraska, South Dakota, North Dakota, and British Columbia (PDF). New York: New York Botanical Garden.
- Schiemann, Donald Anthony (2005). Wildflowers of Montana. Missoula, MT: Mountain Press Publishing. ISBN 0-87842-504-7.
- "Montana Field Guide-Dicotyledoneae". Montana Natural Heritage Program. Retrieved 2011-06-16.
- Species of Concern are native taxa that are at-risk due to declining population trends, threats to their habitats, restricted distribution, and/or other factors. Designation as a Montana Species of Concern or Potential Species of Concern is based on the Montana Status Rank, and is not a statutory or regulatory classification. Rather, these designations provide information that helps resource managers make proactive decisions regarding species conservation and data collection priorities. See the latest Species of Concern Reports for more detailed explanations and assessment criteria. "Montana Field Guide-Species of Concern". Retrieved 2010-12-07.
- Exotic species have been deliberately or accidentally introduced to areas outside of their native geographic range and are able to reproduce and maintain sustainable populations in these areas. These exotic populations may also be referred to as alien, introduced, invasive, non-native, or non-indigenous. "Species Status Codes, Exotics". Montana Natural Heritage Project. Retrieved 2011-06-17.
- Hamilton, Alan; Hamilton, Patrick (2006), Plant conservation : an ecosystem approach, London: Earthscan, p. 2, ISBN 978-1-84407-083-1