If you want to get serious about your wildflower IDs, one of the first things to learn is the flower shape that characterizes most members of the pea family. Click here for the Wikipedia article that describes the shape.
Flowers are organized alphabetically by genus and species. Hover over a photo series to control the images.
False Indigo-Bush (Amorpha fruticosa)
This bush can grow to above head height.
Milkvetch (Astragalus spp.)
Be warned: there are dozens of species of Astragalus in New Mexico, including multiple species each with purple or white flowers. (Or they have flowers of both colors.) There are also dozens of varieties within the state's known species. One of my go-to reference sites, focused on southwest Colorado, notes that " Astragalus keys ... are complex, running to many pages, and it is the seed pod, not the flower, that is almost always crucial in identifying species." I'll add that any IDs based solely on pictures, such as these ones, should be considered tentative. Having said all that, let's look at a few pictures.
Based on the seed pods, I believe that the pictures shown immediately above are of beakpod milkvetch (Astragalus lentiginosus).
The seed pods on the milkvetch shown above lead me to think it's crescent milkvetch (Astragalus amphioxys). In the image of a whole plant, the milkvetch's leaves are partly hidden behind a tuft of grass.
I didn't see any seed pods to go with the white flowers shown above, so I won't hazard a guess as to the species.
Bird of Paradise (Caesalpinia gilliesii)
A South American plant introduced to New Mexico as an ornamental, and now an escapee into the wild. Besides the showy yellow flowers, look for finely divided compound leaves and thin seed pods. As the pods dry they turn light brown and split open, with each half of the pod twisting into a spiral.
Eastern Redbud (Cercis canadensis)
Eastern redbuds are not native to New Mexico. Their springtime bursts of pink flowers make them a popular addition to Albuquerque gardens, and at least one has colonized the Bosque.
Bladder-Senna (Colutea arborescens)
As I walked the picnic area road from Sulphur Canyon to Cienega Canyon, on a cold November morning, my eyes were caught by a number of head-high bushes with "inflated" seed pods. I found more examples along the bottom of Cienega Canyon. A few of the compound leaves hadn't yet died. When I returned the following June, the same bushes were covered with egg-yolk yellow flowers. Bladder-sienna is an Old World species widely used as an ornamental, and sometimes it escapes into the wild.
White Prairie Clover (Dalea candida)
Featherplume, Feather Dalea (Dalea formosa)
When this shrub isn't in flower, I don't know that I could identify it. When they do flower, the purple is something a Roman emperor might envy. Yellow "banner petals" are sometimes also present. The calices that hold the flowers are surprisingly hairy.
Woolly Prairie Clover (Dalea Lanata)
Foxtail Prairie Clover (Dalea leporina)
My tentative identification of these plants as Dalea leporina is based in part on known distributions. The similar-looking D. albiflora doesn't extend into the Albuquerque area.
Prairie Bundleflower (Desmanthus illinoensis)
In September 2021 I encountered a new plant with fine, acacia-like leaves and odd rounded seed balls. When I pulled apart a seed ball, it turned out to consist of tiny curved seed pods. In July 2023 I again encountered this species and saw the flowers, which look like little white puffs.
As the scientific and common name suggest, this plant is more common in the Midwest than it is in New Mexico. Still, you can find it up and down the local stretch of the Rio Grande. According to the SEINET web page for this species, "The seed pods are perhaps the most distinctive part of this plant, as they are in such dense rounded clusters near the tops of the stems. There are several other species of Desmanthus in the Southwest, but this is the only one with crescent-shaped seed pods; the other species have straight, linear seed pods."
Honey Locust (Gleditsia triacanthos)
The signature feature of this tree is the wicked-looking thorns. Sometimes the thorns have thorns.
The fully dried seed pods are dark brown. My series includes a photo with bicolor (yellow and brown) seed pods. I've only seen that color pattern a couple of times; I suspect it can happen as the pods dry out.
American Licorice, Wild Licorice (Glycyrrhiza lepidota)
American licorice flowers are often described as white but as one of my photos shows, they can have traces of purple. Look for pea-like flowers that form long points and for "pinnate" leaves. The root of this plant is used by herbalists.
Camote de Ratón, Hog Potato (Hoffmannseggia glauca)
Other English names for this species include Indian rushpea, waxy rushpea, pignut, and shoestring weed. The tubers can be eaten but often were fed to pigs.
Bush Vetchling (Lathyrus eucosmus)
At first I thought this was American vetch (below), but the leaves were too pointy. Besides, the flowers were too lush and two-toned to be that species.
Everlasting Pea, Perennial Peavine (Lathyrus latifolius)
Everlasting pea blooms range from bright purple to white. The best hotspot I knew for this glamorous introduced species was Carlito Springs Open Space, at the south end of the Sandias. Unfortunately, the open space closed for years. I've been back since it reopened, but haven't relocated the patch yet.
In June 2021 I encountered a few everlasting pea vines along a shady drainage ditch at the end of a large, heavily watered commercial lawn. In July 2023 I came across many more along the upper Santa Fe River, at the east edge of town.
Nevada Pea (Lathyrus lanszwertii)
Littlefield and Burns use older terms for this species: white peavine and Lathyrus leucanthus.
Black Medic (Medicago lupulina)
An introduced species, and in lawns easily mistaken for clover. Look for the small balls of tiny yellow flowers.
Alfalfa (Medicago sativa)
In July 2020 I was walking on a mowed lawn in an Albuquerque city park when I noticed "clover" plants, but with flowers that were too big to be clover flowers—tiny as they were—and the wrong color. Normally alfalfa grows to a height of a foot or more, but apparently it can survive as a lawn weed. My ID is based on the purple pea-like flowers and the three-part leaves whose ends are slightly serrated and slightly blunted. The butterfly in one of the photos is a Marine Blue.
Since then I've noticed alfalfa trying to establish itself in various spots around town. I figure that birds help spread the seeds from alfalfa fields (which are common outside town). Usually the escapees struggle to make it, but I found a lush patch in the Bosque in June 2021. Because I'm holding a sprig, you can get a sense of how small the flowers are.
White Sweetclover (Melilotus albus)
Yellow Sweetclover (Melilotus officinalis)
Purple Locoweed (Oxytropis lambertii)
Slimflower Scurfpea (Pediomelum tenuiflorum)
Look for tiny purple flowers, sometimes (as here) with mostly white ones on the same stem; leaves mostly in triples on the upper part of the plant; and leaves in fours or fives towards the base of the plant.
James' Rushpea (Pomaria Jamesii)
Screwbean Mesquite, Mezquite Dulce, Tornillo (Prosopis pubescens)
The easy way to ID this tree is the unmistakable spiral seed pods. I tend to associate this shrub-to-tree-sized species with the Sonoran Desert, but there's also a concentration along the Rio Grande from the Big Bend up to Albuquerque. The seeds are nutritious, but only after extensive processing. The thorns are small but not to be ignored.
Broom Dalea (Psorothamnus scoparius)
Near the Sunport I came across low bushes that looked like nothing but stems. When I looked more closely, the bushes had clusters of small purple pea-like flowers, plus a few leaves that were usually three-lobed. The stems and leaves were dotted with glands.
New Mexico locust (Robinia neomexicana)
Black Locust (Robinia pseudoacacia)
This non-native species is most easily distinguished from its New Mexico cousin by having white rather than pink flowers. It exists both as a planting and as an escapee (the latter sometimes in empty lots).
Alkali Swainsonpea (Sphaerophysa salsula)
This species is non-native and invasive. (The Rio Grande Nature Center has large patches of it, and can't get rid of it.) Like the Astragalus I show above, this species has inflated seed pods; unlike that Astragalus, the pods are rounded at the ends.
Golden Pea (Thermopsis montana)
A couple of the photos show the erect pea pods that result from these showy flowers. The pods start out bright green and turn dark.
Red Clover (Trifolium pratense)
An introduction from the Old World, valued as fodder and for its ability to fix nitrogen. If you're lost in the woods and desperate to fill your belly, red clover leaves and flowers are edible.
White Clover (Trifolium repens)
Yes, the same stuff that's in lawns everywhere. But you might encounter it in the wild, so I've included it.
American Vetch (Vicia americana)
A clinging, climbing vine, with clusters of just a few purple flowers. On the closeup without my thumb and finger, you can see a tendril at the end of the leaf. The plant uses the tendrils to anchor itself.